ECONOMIC AND FINANCIAL EVALUATION STUDY: GUYANA - AMAILA FALLS HYDRO PROJECT REPORT Prepared for: Government of Guyana November, 2009 Revised March 2010 – Final version R1056-09 A0078 ECONOMIC AND FINANCIAL EVALUATION STUDY: GUYANA - AMAILA FALLS HYDRO PROJECT CONTENTS FOREWORD .......................................................................................................................................... 5 EXECUTIVE SUMMARY........................................................................................................................ 7 1. 2. 3. 4. 5. 6. GENERAL FRAMEWORK ............................................................................................................... 7 DEMAND FORECAST .................................................................................................................... 8 LEAST COST EXPANSION PLAN ..................................................................................................... 9 COST-BENEFIT ANALYSIS .......................................................................................................... 10 COMPETITIVENESS OF AMAILA FALLS ........................................................................................ 12 SENSITIVITY ANALYSIS .............................................................................................................. 14 6.1. CRUDE OIL PRICES ......................................................................................................... 14 6.2. MARKET EXPANSION ....................................................................................................... 15 7. REVIEW ON HYDROLOGY STUDIES AND PLANT DESIGN ................................................................. 16 8. MAIN CONCLUSIONS ................................................................................................................. 18 SECTION I: FUNDAMENTALS OF THE ANALYSIS.......................................................................... 22 1. 2. 3. INTRODUCTION ......................................................................................................................... 22 ECONOMIC RATIONALE .............................................................................................................. 22 PROJECT BACKGROUND ............................................................................................................ 23 3.1. AMAILA FALLS PHYSICAL SETTING .................................................................................. 23 3.2. GUYANA POWER SECTOR OVERVIEW ............................................................................... 24 3.2.1. Self generation ................................................................................................................25 3.2.2. Linden area .....................................................................................................................26 SECTION II: DEMAND FORECAST.................................................................................................... 27 1. ELECTRICITY DEMAND DRIVERS ................................................................................................. 27 1.1. MACROECONOMIC GROWTH ............................................................................................ 27 1.2. EXTRA-TENDENCY GROWTH IN THE SHORT RUN ............................................................... 27 2. REGRESSION MODELS .............................................................................................................. 28 2.1. FORECAST OF THE INDEPENDENT VARIABLE (GDP).......................................................... 29 2.2. ELECTRICITY DEMAND PROJECTION (GPL) ...................................................................... 30 2.3. ELECTRICITY DEMAND IN LINDEN AREA ............................................................................ 33 2.4. SELF-GENERATION ......................................................................................................... 33 SECTION III: COST-BENEFIT ANALYSIS FOR AMAILA FALLS PROJECT................................... 35 1. 2. LEAST COST EXPANSION PLAN ................................................................................................... 35 KEY ASSUMPTIONS ................................................................................................................... 36 2.1. DEMAND FORECAST ....................................................................................................... 36 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 2 2.2. FUEL PRICES .................................................................................................................. 38 2.3. TYPE OF TECHNOLOGY TO EXPAND THE POWER SYSTEM................................................... 38 2.4. COSTS OF AMAILA FALLS PROJECT ................................................................................. 40 3. LEAST COST EXPANSION PLAN ................................................................................................... 41 3.1. NEW GENERATING CAPACITY........................................................................................... 42 3.2. EXPECTED DISPATCH OF POWER PLANTS ......................................................................... 43 4. COST-BENEFIT ANALYSIS ........................................................................................................... 45 4.1. COST STREAM ................................................................................................................ 45 4.2. BENEFIT STREAM............................................................................................................ 45 4.2.1. 4.2.2. 4.2.3. 4.2.4. 4.3. 4.4. 4.5. Direct savings in fuel consumption..................................................................................45 Direct savings in O&M of thermal generation fleet ..........................................................46 Direct savings in capital expenditures in new thermal facilities .......................................46 Carbon emissions reduction............................................................................................47 COSTS AND BENEFITS STREAM ........................................................................................ 47 NET PRESENT VALUE OF THE PROJECT AND ECONOMIC RATE OF RETURN ........................... 48 OPPORTUNITY COST FOR GPL (MAXIMUM ANNUAL FIXED PAYMENT) ................................. 55 SECTION IV: COMPETITIVENESS OF AMAILA FALLS SUPPLY COST ........................................ 56 5. 6. GPL SUPPLY COST................................................................................................................... 56 COST OF SELF GENERATION ...................................................................................................... 57 SECTION V: SENSITIVITY ANALYSIS............................................................................................... 59 7. 8. SENSITIVITY TO CRUDE OIL PRICE .............................................................................................. 59 SENSITIVITY TO MARKET EXPANSION .......................................................................................... 60 8.1. UPSIDE CASE ................................................................................................................. 60 8.2. DOWNSIDE CASE ............................................................................................................ 61 SECTION VI: REVIEW OF EXISTING HYDROLOGY STUDIES........................................................ 62 SECTION VII: MAIN CONCLUSIONS ................................................................................................. 64 ANNEX I – SIMULATION MODEL OUTPUTS .................................................................................... 67 ANNEX II – SELF GENERATORS SURVEY ...................................................................................... 74 ANNEX III – REVIEW OF EXISTING HYDROLOGY STUDIES.......................................................... 86 1. 2. 3. 4. EXECUTIVE SUMMARY ............................................................................................................... 87 INTRODUCTION ......................................................................................................................... 88 PROJECT DESCRIPTION ............................................................................................................. 88 SUMMARY OF KEY PROJECT FEATURES ..................................................................................... 89 4.1. DAMS AND SPILLWAY ...................................................................................................... 89 4.1.1. Amaila Dam.....................................................................................................................89 4.1.2. Kuribrong Dam ................................................................................................................90 4.2. 4.3. 4.4. 4.5. 4.6. 4.7. 4.8. INTAKE AND HEADRACE TUNNEL ..................................................................................... 90 SURGE AND POWER SHAFT ............................................................................................ 90 POWER TUNNEL ............................................................................................................. 90 LOWER HEADRACE TUNNEL AND SURFACE PENSTOCK ALTERNATIVE ............................... 90 POWERHOUSE ............................................................................................................... 91 TAILRACE CHANNEL ....................................................................................................... 91 SWITCHYARD ................................................................................................................. 91 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 3 4.9. KURIBRONG BRIDGE ....................................................................................................... 91 HYDROLOGY ASPECTS.............................................................................................................. 91 5.1. SITUATION OF AMAILA PROJECT...................................................................................... 92 5.2. TOPOGRAPHY AND CONTRIBUTING BASINS DRAINAGE ....................................................... 92 6. OBTAINING THE RESERVOIR’S HYDROLOGY PARAMETERS............................................................ 93 6.1. DETERMINATION OF AVERAGE MONTHLY AND ANNUAL FLOWS ........................................... 93 6.2. RESERVOIR EVAPORATION .............................................................................................. 95 6.3. PROBABLE MAXIMUM FLOW – OPERATION PERIOD ........................................................... 96 5. 6.3.1. 6.3.2. 6.3.3. 6.3.4. 6.3.5. 6.3.6. 6.3.7. 6.3.8. Estimation of the PMP.....................................................................................................96 Duration of the PMP........................................................................................................96 Temporal distribution of the PMP ....................................................................................97 Losses due to infiltration .................................................................................................97 Unitary diagram...............................................................................................................97 Transformation of PMP into PMF ....................................................................................98 Evaluation of the PMF.....................................................................................................99 Maximum design flow during the construction period......................................................99 7. 8. 9. SEDIMENTATION ..................................................................................................................... 100 CONCLUSIONS ON HYDROLOGY ASPECTS ................................................................................. 100 DAM HEIGHT AND INSTALLED CAPACITY .................................................................................... 101 9.1. METHODOLOGY ............................................................................................................ 101 9.2. RESULTS ..................................................................................................................... 102 10. POSSIBILITIES OF DESIGN VARIATIONS: GENERAL COMMENTS .................................................... 107 10.1. INCREASE IN DAM HEIGHT ............................................................................................. 107 10.2. ENHANCING THE DAM’S REGULATION CAPACITY .............................................................. 107 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 4 ECONOMIC AND FINANCIAL EVALUATION STUDY: GUYANA - AMAILA FALLS HYDRO PROJECT FOREWORD As part of its development strategy for the next five years, the Government of Guyana (GoG) has decided to meet its medium and long term power needs from renewable sources. Guyana has significant hydroelectric resources yet not developed. Amaila Falls was identified, along with several other projects, as a potential hydro development site during studies carried out around 1975 for the first time. In recent years, the Guyana Energy Agency favored Amaila Falls as the first project to develop based on its location and water flows. Synergy Holdings, a Guyanese developer based in the US, obtained the rights to develop Amaila Falls project, performed a feasibility study in 2002 and initiated negotiations with the state-owned utility GPL as the primary off-taker. In the meantime, Synergy joined forces with Enventure (US developer) and later invited Sithe Global to look at this project opportunity. EPC proposals received in Nov 2008 are being analyzed in parallel with a PPA to allow acceptable yearly tariff to pass-through to final customers. In this context, the Government of Guyana and Sithe Global retained Mercados Energéticos Consultores to perform a comprehensive study to ensure that Amaila Falls project is: 1. consistent with the least cost generation expansion option to assure the economic profitability of the hydro power plant project and 2. compatible with the medium and long-term demand projections. This Report is organized as follows: • The Executive Summary highlights key contents of the Report; • Section I summarizes the project background and the economic fundamentals of the study; • Section II describes the electricity demand forecast • Section III analyses the least cost generation expansion plan, the cost-benefit analysis for Amaila Falls project and its economic rate of return. • Section IV discusses the competitiveness of Amaila Falls supply cost compared to GPL’s alternative supply option and to self generation costs. • Section V presents the sensitivity analysis to fuel prices and demand growth on the economic profitability of the project. • Section VI presents the review of the existing hydrological studies • Finally, Section VII summarizes the main conclusions of the study. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 5 • Annexes: 9 Annex I contains tables with the outputs of the simulation model; 9 Annex II reproduces the Report done by Mr. John Cush, local consultant retained by GPL to conduct a survey on self generators; 9 Annex III presents the review of hydrology studies and plant’s design (done by MWH). Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 6 EXECUTIVE SUMMARY 1. GENERAL FRAMEWORK • While the development of the 154 MW Amaila Falls projects is based on the decision to shift from costly and imported fuel sources to using the abundant, domestic water potential, the generation expansion plan has to consider developing the power sector in the most economically efficient manner (i.e. least cost). • Amaila Falls hydro project is expected to cover a significant proportion of the existing power demands in Guyana. As such, the characteristics of the Project must be established in light of the existing and future power system (total installed capacity and size of individual units, power system reliability and stability). • The electricity sector in Guyana is dominated by Guyana Power and Light (GPL), a vertically integrated government-owned utility. • GPL owns and manages 142 MW of installed capacity (2009), all of which is based on thermoelectric plants with diesel-engine driven generators, exposing the sector to price shocks and the inherent volatility of the international oil markets. • Electrification in Guyana is low both in terms of access and in terms of intensity of use relative to other countries in the region. GPL’s gross demand is estimated in 580 GWh-year (2010e). • Losses at the distribution level account for up to 30 % of the energy generated. At the commercial level, the utility is making efforts to enforce collection of bills, and to eradicate theft. • Deficiencies in power infrastructure and low reliability of service in Guyana may pose an important constraint for the development of the country. • According to the World Bank in its Guyana Investment Climate Assessment Report (2007), four aspects of the investment climate were mentioned in the group of top constraints: cost of financing, macroeconomic uncertainty, worker skills and education, and electricity. • A survey recently conducted among the most important self generators registered in the Guyana Energy Agency (GEA) confirmed that self-supply of electricity in Guyana meets a significant proportion of the country’s electricity demand (131 GWh-year, approximately 20 % of GPL’s gross demand), although it is costly and generates economic inefficiencies. • In the Base Case scenario, ME assumed that the total amount of self generation surveyed decides to take power from GPL during the first 2 years of Amaila Falls commercial operation: 60 % of 131 GWh-year in Y 2014 and the remaining 40 % in Y 2015. • Linden Power Company (LPC) is another major customer for Amaila Falls, as the planned transmission line can easily be routed through Linden (66 – 70 GWhyear) Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 7 2. DEMAND FORECAST • The main driver to account for electricity demand growth is the economic activity (GDP) which explains the natural trend in demand growth. • ME forecasted the electricity sales by type of customer as a function of global GDP. Different functional forms were tested for each sector and selected those with best statistical indicators. • Estimated total demand elasticity to GDP growth is 1.75 (i.e. a 3.0 % GDP growth accounts for 5.2 % in demand growth). This elasticity varies among consumption sectors: 1.4 for residential customers and 2.2 for industrial users. • Once the econometric models were specified and its parameters estimated for each consumption sector, ME envisaged a base case macroeconomic scenario to forecast GDP growth: Year 2008 2009 est 2010 est 2011 2012 2013 2014 2015 2016 2017 – 2025 2026 onwards GDP Growth rate% 3.1% 2.2% 2.8% 3.5% 2.8% 2.9% 2.9% 2.9% 2.9% 3.0% 3.1% Sources: Ministry of Finance (2008 figure); own elaboration based on CEPAL and on World Bank projections (2009 onwards) • Besides, in the short run, there are three factors that account for an extra tendency growth of electricity sales within GPL’s serving area: • 9 New connections under un-served areas electrification programmes and current construction boom 9 Reduction in non-served energy due to present generation shortfall 9 Loss reduction programme at the distribution level Demand forecast for the Base Case is shown below: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 8 Demand Forecast GDP growth Total Sales GPL system T & D losses Year % 2009 2.2% 2010 2.8% 2014 2.9% 2015 2.9% 2020 3.0% 2025 3.0% 2030 3.1% 2035 3.1% GWh annual growth 393 418 6.3% 500 5.1% 525 5.1% 677 5.2% 876 5.3% 1,140 5.5% 1,479 5.1% in % Technical 11.4% 10.6% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% Non-technical 21.6% 19.4% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% Gross generation GPL system GWh annual growth 587 597 1.7% 701 4.1% 737 5.1% 949 5.2% 1,229 5.3% 1,599 5.5% 2,073 5.1% Linden Power Company GWh 66 68 2.8% 76 2.9% 79 2.9% 91 3.0% 106 3.0% 123 3.1% 143 2.9% Self generation switching to the grid GWh 0.60 79 0.40 131 152 3.0% 176 3.0% 205 3.1% 239 3.1% Total expected demand Expected demand growth GWh % 653 665 1.8% 856 14.5% 947 10.6% 1,192 4.8% 1,511 4.9% 1,927 5.0% 2,454 4.8% MW MW 75 108 76 110 Average load Peak demand - - 98 142 108 157 136 197 172 250 220 319 Note on GPL gross generation: Y 2009, actual figure. Y 2010, GPL estimation. From then onwards, forecasts are based on econometric models developed by Mercados Energéticos.- 3. LEAST COST EXPANSION PLAN • In order to estimate the economic profitability of Amaila Falls project, ME compared the expansion of the power generation capacity of Guyana with and without Amaila Falls project. • The optimal (least cost) investment schedule to supply the forecasted load was then modeled for two different situations: 1. expansion of the generation capacity fully based on thermal power plants, typically medium speed engines or gas turbines, in both cases using liquid fuels (HFO, LFO) and 2. expansion of the generation capacity considering that Amaila Falls hydro project begins commercial operation in Y 2014. From then onwards, if new capacity additions are needed, they will be thermal plants using liquid fuels. • The objective function was to minimize the expected supply costs, including investment, operational costs and non-supplied energy cost; subject to an adequate reliability of the system’s operation (reserve margin). • The results attained for each capacity expansion situation were next compared to estimate the measurable benefits of Amaila Falls project: • 9 Direct savings in fuel purchases for generation purposes 9 Direct savings in O&M of the thermal generation fleet 9 Direct savings in capital expenditures (new thermal facilities). 9 Carbon emissions reduction Key assumptions are: crude oil prices, expected demand, type of technology selected to expand generation capacity and costs of Amaila Falls project. 9 Crude oil prices directly influence the cost of HFO and LFO which, in turn, account for most part of the variable cost of production of fuel-fired Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 9 280 406 generators. Base case assumes a WTI of 75 USD / bbl (consistent with latest World Bank’s projections). Crude Oil (USD / bbl) 75 HFO (USD / bbl) LFO (USD / bbl) FOB Freight CIF FOB Freight CIF 56.1 5.8 61.9 91.6 5.8 97.4 Source: own estimates based on a linear correlation of fuel prices as a function of crude oil prices. 9 Type of technology to expand the system: ME estimated the development cost of HFO medium speed engines and LFO-fired gas turbines. HFO medium speed engines was the favored (least cost) technology for relative high dispatch factors. The long run marginal cost for such technology is around 13.0 – 14.0 ¢USD / kWh, assuming a crude oil price of 75 USD / bbl. 9 Costs of Amaila Falls project: provided by the Client. PPA consists of a fixed annual payment of -105,000 k USD (take-or-pay). • Model results for each expansion alternative analized (with and without Amaila Falls) include: new capacity additions (size, time) necessary to meet expected load, expected dispatch of power plants and operational costs and generation reserve margin 1. • Amaila’s expected average energy production (983 GWh) is well-matched with expected demand growth driven by existing GPL / Linden customers; and the addition of 131 GWh-year of self generation as of 2014. • As of Y 2022 increasing amounts of thermal generation are needed, on top of Amaila mean energy production, to meet expected demand and to keep a reasonable reserve margin in the system. 4. COST-BENEFIT ANALYSIS • Cost stream: Fixed annual payment for Amaila Falls energy production of 105,000 k USD during 20 years. • Benefits stream: the economic benefits of the project were identified and measured, by category, over the study time horizon (40 years): 9 Direct savings in fuel consumption: represent approximately 68 % of total economic benefits (80,000 – 85,000 k USD per year). 9 Direct savings in O&M costs of thermal facilities: represent around 2 % of total economic benefits identified (2,300 – 2,500 k USD per year). Amaila’s output is subject, by definition, to hydro volatility (there are some months of the year when thermal plants are needed to meet the portion of demand load that can not be met by Amaila’s production). 1 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 10 9 Direct savings in capital expenditures in new thermal units: account for approximately 24 % of total economic benefits (29,000 k USD per year). 9 Carbon emissions reduction: add around 6,200 – 6,500 k YSD per year to total benefits (5 %). • Amaila’s fixed costs are evenly distributed over 20 years while Amaila’s benefits are mostly concentrated on medium to long term. This is variable and mostly depends on expected market development and oil prices. • Annual costs and benefits are shown in the graph below: Amaila Falls Project: Costs and Benefits Stream 160,000 Savings in O&M costs Carbon credits 140,000 120,000 100,000 Savings in CAPEX (thermal units) in thousand US dollars per year 80,000 60,000 Savings in liquid fuel costs 40,000 20,000 2037 2036 2035 2034 2033 2032 2031 2030 2029 2028 2027 2026 2025 2024 2023 2022 2021 2020 2019 2018 2017 2016 2015 -20,000 2014 - -40,000 Fixed annual payment (PPA): -105,000 k USD -60,000 -80,000 -100,000 -120,000 Savings in Fuel Costs • Savings in CAPEX annual payments Total Costs 186,886 83% 0.70 If carbon credits are not considered in the project’s benefits, the above economic indicators are the following: NPV (kUSD) (@ 12%) ERR Benefit - Cost Ratio BCR • Carbon Credits Under the set of assumptions adopted, the net present value of the project cash flow is, the economic rate of return (ERR) and the Benefit-cost ratio (BCR) are the following: NPV (kUSD) (@ 12%) ERR Benefit - Cost Ratio BCR • Savings in O&M Expenses 132,390 32% 0.66 It’s also worth mentioning that in the Base Case there is only one year (the first one) of project’s cash flow when costs exceed economic benefits by 5.9 million USD. This is so because Amaila’s fixed costs are evenly distributed over 20 years while Amaila’s benefits are mostly concentrated on medium to long term. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 11 If a more aggressive market expansion is assumed, this effect reverses, because fixed costs are burdened by a larger demand. • ME also estimated the maximum fixed annual payment (GPL’s opportunity cost) for Amaila’s output which verifies that the present value of GPL’s total generation expenses (CAPEX and OPEX) is equal in both capacity expansion options analyzed. The said annual fixed payment is – 122,724 k USD, considering Base Case assumptions. • Even though this ceiling payment assures Amaila’s structural competitiveness compared to GPL’s thermal expansion option (opportunity cost), it also creates a financial constraint on GPL in the short to medium term: supply costs including Amaila are higher than supply costs deselecting Amaila as a candidate project. • In turn, high average supply costs relative to other supply choices, discourage market expansion and increases demand risk for GPL. • Therefore, ME re-estimated the maximum fixed annual payment assuming a relative more conservative scenario: no self generators decide to purchase power from GPL (because there would be no room for tariff incentives to attract new customers) and a higher discount rate (14%) than Base Case because GPL’s demand risk increases. The annual fixed payment in this stressed scenario drops to – 106,785 k USD. • The table below summarizes key assumptions for each estimated maximum fixed annual payment: Crude Oil (USD / bbl) Base Case 75 75 Discount Rate 12% 14% Demand same as Base Case without self generators GPL's maximum annual payment for Amaila's output # of initial years when costs exceeds benefits -122,724 -106,785 20 7 Note: carbon credits are not considered among total economic benefits.- 5. COMPETITIVENESS OF AMAILA FALLS • Amaila Falls hydro power plant project will sell its energy output primarily to GPL, at a fixed annual payment of -105,000 k USD, regardless actual demand. In other words, the power purchase agreement is a take-or-pay contract. • Amaila Falls project will be competitive if other supply options available for GPL (or any other off-taker) have higher prices than Amaila’s supply cost (PPA). • Supply option for GPL: GPL’s least alternative (to Amaila Falls) supply cost is the long run marginal cost (LRMC) of the most competitive thermal technology available to expand its power system (bunker-fired engines). Such LRMC is in between 13.0 and 14.0 ¢USD / kWh, estimated with the following set of assumptions: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 12 Expansion Technology: HFO medium speed engines Parameter Investment Cost 1,100 USD / kW Return on equity 16.07 % Repayment period 10 years O&M 0.9 ¢USD / kWh Type of fuel Heavy fuel oil Fuel cost on site 61.9 USD / bbl (Crude oil 75 USD / bbl) Gross capacity 7 MW 40 % Heat rate 2,158.9 kCal / kWh 56.4 Gal / MWh Expected dispatch 2 70 % • Synthetic economic indicators of the cost-benefit analysis show that the inclusion of Amaila Falls in GPL’s generation expansion plan lowers the net present value of GPL’s generation expenses. • The inclusion of Amaila Falls cuts down GPL’s average supply costs to 11.5 ¢USD / kWh in the medium to long term. • However, in the early years of the project (first year of Amaila’s operation in the Base Case) and given that contractual arrangement is take-or-pay, GPL’s total generating expenses including the power purchase agreement with Amaila Falls are closer or even 5 - 10 % higher than GPL’s generation expenses without including Amaila Falls (and only adding needed thermal generators to meet demand growth) • Market expansion mitigates this short run effect because the fixed annual payment is absorbed by a larger demand. • In any case, GPL’s degree of success in attracting industrial self generators back to the grid, will depend on the tariff2 at which GPL can deliver the energy to such customers compared to their self-generation cost. • Based on data collected in the self generators survey and own assumptions, ME estimated the following costs of self-generation (assuming a crude oil price of 75 USD / bbl): 9 between 19.3 – 20.7 ¢USD / kWh, for an industry assessing the costs of installing a new power generator. 9 between 15.8 and 17.2 ¢USD / kWh for existing self generators (does not include investment cost – sunk cost -, only operating costs). Reliability of service will also play a key role in market expansion Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 13 • The above estimated self generation costs represent the break-even price for an industrial customer, assuming same reliability in supply options (GPL vs self generation). • The cost of self generation (both for prospective and existing self generators as well) is higher than GPL’s average supply costs. • It’s worth noting that these figures are not directly comparable with GPL’s supply cost (transmission and distribution charges have to be added). 6. SENSITIVITY ANALYSIS 6.1. CRUDE OIL PRICES • Variable operating costs for thermal plants mostly depend on fuel costs. Direct savings in fuel costs account for approximately 68 % 3 of total economic benefits of Amaila Falls project. • Future scenarios of high crude oil prices contribute to increase the competitiveness of Amaila Falls vis a vis the thermal expansion (upside). Conversely, scenarios of low crude oil prices are a downside for the project. • The following table shows the economic indicators of the cost-benefit analysis for different scenarios of future crude oil prices, with and without considering carbon credits as part of the total benefits): Sensitivity to WTI (net cash flow includes carbon credits).- Crude Oil price NPV (@ 12%) Base Case (*) Downside Cases USD / bbl 75 70 65 60 55 k USD 186,886 145,052 103,217 61,383 19,549 ERR BCR (**) in % 83% 37% 23% 17% 13% 0.70 0.67 0.64 0.61 0.58 # of initial years with negative cash flow (cost > benefits) 1 2 4 6 8 (*) consistent with World Bank's latest projections (**) Benefit - Cost ratio = NPV (Benefits) / NPV (Costs) Time horizon: 40 years Sensitivity to WTI (net cash flow does not include carbon credits).- Crude Oil price NPV (@ 12%) Base Case (*) Downside Cases USD / bbl 75 70 65 60 55 k USD 132,390 90,556 48,721 6,887 -34,947 ERR in % 32% 21% 16% 12% 10% BCR (**) 0.66 0.63 0.60 0.57 0.54 # of initial years with negative cash flow (cost > benefits) 3 5 7 8 20 Avoided costs in fuel consumption for generation purposes are in the range of 80,000 to 85,000 thousand dollars per year. 3 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 14 ERR stands for Economic Rate of Return 6.2. MARKET EXPANSION • In the short run, annual fixed payment for Amaila’s output may outweigh the direct savings in operating costs and capital expenditures in new thermal generators. Instead, in the medium to long run benefits outweigh the costs. • Market expansion contributes to compensate the temporary imbalance between total costs and total benefits. • The following table shows the project’s economic indicators for different scenarios of market expansion: Sensitivity to market expansion Scenario Base Case (*) Upside Case Self generators switching to the grid GWh-year 131 GWh (60 % in 2014 & 40 % in 2015) NPV (@ 12%) Economic rate of return (ERR) Benefit / Cost ratio k USD in % BCR # of initial years with negative cash flow (costs larger than benefits) 186,886 83% 0.70 195,664 positive cash flow all years 0.71 105 GWh as of Y 2014 170,318 49% 0.69 2 79 GWh as of Y 2014 153,363 34% 0.68 3 100,870 19% 0.64 7 131 GWh as of Y 2014 1 zero Downside Cases: 20% less than BC 40 % less than BC Self generators decide not to switch to the grid • Upside case: If it is assumed that 100 % of estimated self generation (131 GWh-year) is connected to the grid during the first year (2014) of Amaila Falls operation 4, benefits outweigh costs since the beginning (2014): Instead of assuming that only 60 % of 131 GWh switches to the grid during the first year (2014) and the remaining 40 % of self generation connects to the grid during the second year (2015).- (Base Case)4 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 15 GPL's generating expenses per unit of demand With and without Amaila Falls in the expansion plan 16.0 15.5 15.0 14.5 14.0 100 % Thermal Expansion in cUSD / kWh 13.5 13.0 12.5 12.0 11.5 Expansion with Amaila as of Y 2014 (includes carbon credits) 11.0 10.5 10.0 Y 2014: Amaila Falls begins commercial operations 9.5 20 36 20 37 20 34 20 35 20 32 20 33 20 30 20 31 20 28 20 29 20 26 20 27 20 24 20 25 20 23 20 21 20 22 20 19 20 20 20 17 20 18 20 15 20 16 20 13 20 14 20 11 20 12 20 09 20 10 9.0 7. REVIEW ON HYDROLOGY STUDIES AND PLANT DESIGN • The design of Amaila Falls Project encountered several problems arising from the lack of hydrologic data. Therefore, the best techniques available were applied to cope with the lack of information but even so, several questions remained unanswered, such as the following: 9 The flows used were obtained by extrapolating the results from Kaieter Falls Station with different transfer coefficients and then adopting 0.30 without further justification. This may cause some uncertainty regarding the expected power generation. 9 The maximum flow adopted to design the dam was the result of transforming the Probable Maximum Precipitation value into the Probable Maximum Flow by adopting a C coefficient (Creaguer’s formula) that has no direct justification, thus causing uncertainty as regards the maximum flow adopted for the design at 5.010 m3/s. 9 In addition, the Probable Maximum Flood was assessed in the current basin status, with no deforestation or mining exploitation. Any modification of the basin in such respect will have an impact on the increase in the maximum value considered. 9 The flows assumed for different return periods, which set the maximum values to be adopted during the construction period, also include coefficients and parameters adopted without any actual data on the site. 9 In order to obtain more accurate information, it would be desirable to install a hydro-meteorological station in a section of the river that is representative Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 16 of the Project. Even if the works start soon, the information obtained will always be useful and will allow future adjustment of the parameters necessary for operation. • • With respect to the studies conducted on the behavior of generation with different dam heights and installed capacities, it was concluded that: 9 Energy production is marked by hydraulicity in the different months of the year. In wet months (June to September), more power can be generated and demand is covered. 9 In months with low hydraulicity, demand is only partially covered. 9 The above shows the reservoir’s poor regulation, considering that in wet months or periods the surplus flows will be spilled. 9 As the reservoir level is increased (more regulation) or installed capacity is reduced, the percentage of demand coverage grows for the same load factor. 9 In the actual case, 140 MW at delivery point and maximum reservoir level at 462.00 m.a.s.l., the trend is confirmed: even with smaller load factors, there is a deficit in power generation in months with low hydraulicity. The potential increase in dam height will have little influence on the installed capacity due to the great existing fall, although it will improve annual power generation, considering the greater regulation capacity and the following features: 9 The increase in the maximum level from 462 to 468 m 5 represents an increase of 26 % in the maximum height of Amaila Dam and 30 % in Kuribrong Dam, with major economic implications. 9 In addition to more investment, other aspects linked to the larger flooded area should be considered, in particular, associated environmental aspects. 9 Another alternative to enhance the dam’s regulation capacity, and therefore its annual average energy, could be the implementation of circular sector gates allowing some of the flows in wet months to be stored, thus reducing spilling. (Source: own elaboration based on consultant’s experience and consultant’s review of information on Amaila Falls). 9 It is considered, however, that this additional regulation capacity would be limited and equal to approximately only 10% of the annual spilling (Source: own elaboration based on consultant’s experience and consultant’s review of information on Amaila Falls). 9 The convenience of installing gates to reduce the expected investment remains to be considered (Source: own elaboration based on consultant’s experience and consultant’s review of information on Amaila Falls). Source: PPA multiscenario_Covermemo_20090820.pdf, prepared by MWH. It estimates monthly energy generation for different scenarios. 5 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 17 8. MAIN CONCLUSIONS • Amaila Falls project brings structural benefits to the power system: a generation mix hydro-thermal is better to hedge risks (oil prices volatility) than a system that entirely relies on thermal plants. • Cost – benefit analysis evidences that the project is economically profitable. The inclusion of Amaila Falls in GPL’s expansion plan reduces GPL’s net present value of generation expenses throughout the study time horizon. • In other words, total benefits outweigh total costs. • It’s worth noting that Amaila Falls benefits are mainly concentrated in the medium to long term, while PPA is evenly distributed during 20 years. • Assuming a WTI of 75 USD / bbl, an annual demand growth of 5 % in the steady state (consistent with a GDP growth of 3.0 %) and the addition to the grid of 131 GWh currently self generating (60 % in 2014 and 40 % in 2015), the project’s economic indicators are the following: NPV (kUSD) (@ 12%) ERR Benefit - Cost Ratio BCR • 186,886 83% 0.70 If carbon credits are not considered in the project’s benefits, the above economic indicators are the following: NPV (kUSD) (@ 12%) ERR Benefit - Cost Ratio BCR 132,390 32% 0.66 • GPL’s least alternative supply cost is the long run marginal cost (LRMC) of the most competitive thermal technology available to expand its power system (bunker-fired engines). Such LRMC is in between 13.0 and 14.0 ¢USD / kWh, assuming a crude oil price (WTI) of 75 USD / bbl. • The inclusion of Amaila Falls in the capacity expansion plan at a fixed annual payment of 105,000 k USD lowers net present value of GPL’s generation expenses throughout the study time horizon, as demonstrated in the costbenefit analysis. • Competitiveness: The inclusion of Amaila Falls cuts down GPL’s average supply costs to 11.5 ¢USD / kWh in the medium to long term. • In the short run, GPL’s average supply costs are higher than in the long term, in the order of 12.6 ¢USD / kWh (effect of a take-or-pay contractual arrangement and demand lower or close to energy delivered). • Market expansion by attracting industrial self generators back to the grid mitigates this short run effect because the fixed annual payment is absorbed by a larger demand. • Costs of self-generation (assuming a crude oil price of 75 USD / bbl) are estimated between 15.8 and 20.7 ¢USD / kWh. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 18 • These figures represent the break-even price for an industrial customer assessing the convenience of being supplied by the grid or self-generate, assuming same reliability in supply options (GPL vs self generation). • The cost of self generate is larger than GPL’s average supply costs, both in the short run (around 12.6 ¢USD / kWh) and in the medium-long term (11.5 ¢USD / kWh). The graph below illustrates these costs. • It’s worth noting that the above mentioned figures (cost of self generation vs GPL’s average supply cost) are not strictly comparable. In fact, transmission and distribution charges should be added to GPL’s average supply cost and then compared to the cost of self-generate. GPL's generating expenses and Costs of self generation 21.0 20.5 20.0 19.5 Prospective self generator Total costs (includes capital expenditures) 19.0 18.5 18.0 17.5 in cUSD / kWh 17.0 16.5 Existing self generators Variable costs 16.0 15.5 15.0 14.5 14.0 13.5 100 % Thermal Expansion 13.0 12.5 12.0 11.5 11.0 20 36 20 37 20 34 20 35 20 32 20 33 20 30 20 31 20 28 20 29 20 26 20 27 20 24 20 25 20 23 20 21 20 22 20 19 20 20 20 17 20 18 20 15 20 16 20 13 20 14 20 09 20 10 10.0 Expansion with Amaila as of Y 2014 Note: GPL's generating expenses (T&D charges are not included) 20 11 20 12 10.5 • Sensitivity to WTI: future scenarios of high crude oil prices contribute to increase the competitiveness of Amaila Falls vis a vis the thermal expansion (upside). Conversely, scenarios of low crude oil prices are a downside for the project. • The following tables show the economic indicators of the cost-benefit analysis for different scenarios of future crude oil prices, with and without considering carbon credits as part of the total benefits): Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 19 Sensitivity to WTI (net cash flow includes carbon credits).- Crude Oil price NPV (@ 12%) Base Case (*) Downside Cases USD / bbl 75 70 65 60 55 k USD 186,886 145,052 103,217 61,383 19,549 ERR BCR (**) in % 83% 37% 23% 17% 13% # of initial years with negative cash flow (cost > benefits) 0.70 0.67 0.64 0.61 0.58 1 2 4 6 8 (*) consistent with World Bank's latest projections (**) Benefit - Cost ratio = NPV (Benefits) / NPV (Costs) Time horizon: 40 years Sensitivity to WTI (net cash flow does not include carbon credits).- Crude Oil price NPV (@ 12%) Base Case (*) Downside Cases USD / bbl 75 70 65 60 55 k USD 132,390 90,556 48,721 6,887 -34,947 ERR in % 32% 21% 16% 12% 10% # of initial years with negative cash flow (cost > benefits) BCR (**) 0.66 0.63 0.60 0.57 0.54 3 5 7 8 20 ERR stands for Economic Rate of Return • The number of initial years with negative cash flow (i.e. costs greater than benefits) increase as WTI decreases, because direct savings in fuel costs are reduced • Sensitivity to market expansion: In the short run, annual fixed payment for Amaila’s output may outweigh the direct savings in operating costs and capital expenditures in new thermal generators. Instead, in the medium to long run benefits outweigh the costs. • Market expansion contributes to compensate the temporary imbalance between total costs and total benefits. • The following table shows the project’s economic indicators for different scenarios of market expansion: Sensitivity to market expansion Scenario Base Case (*) Upside Case Self generators switching to the grid GWh-year 131 GWh (60 % in 2014 & 40 % in 2015) NPV (@ 12%) Economic rate of return (ERR) Benefit / Cost ratio k USD in % BCR # of initial years with negative cash flow (costs larger than benefits) 186,886 83% 0.70 195,664 positive cash flow all years 0.71 105 GWh as of Y 2014 170,318 49% 0.69 2 79 GWh as of Y 2014 153,363 34% 0.68 3 100,870 19% 0.64 7 131 GWh as of Y 2014 1 zero Downside Cases: 20% less than BC 40 % less than BC Self generators decide not to switch to the grid Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 20 • The number of initial years with negative cash flow (i.e. costs greater than benefits) increases as market expansion decreases. • High supply costs in the short run might be mitigated considering efficient contractual arrangements (fuel cost deduction during dry seasons, increasing annuity over time, etc.) • Review on hydrology studies: The hydrology study done by MWH encountered some difficulties due to lack of direct hydrological data at the project site. Given the above mentioned constraint, MWH applied best practices to process the available information. • Reservoir operation: Seasonal regulation and production of firm energy during drier months is limited. • The optimization of the project design is limited because all available data has been already considered. Design improvements would require additional hydrological data collection. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 21 SECTION I: FUNDAMENTALS OF THE ANALYSIS 1. INTRODUCTION Guyana has substantial hydroelectric resources, but due to the complicated terrain and the small size of the country the development of these resources has been delayed. The developer, Synergy Holdings, performed an initial feasibility study undertaken by Harza (MWH) in 2002 and advanced negotiations with GPL, the state-owned utility, primary off-taker of Amaila energy production. However, the privatization of GPL and later re-purchase by the Government delayed the development of the project. EPC proposals were received Nov 2008, they include proposals from three Chinese consortia, one Italian company and from one Indian-led consortium. The Government of Guyana would potentially allow for this project to move forward based on an acceptable yearly tariff. Next steps include: to finalize discussions related to the PPA aspects, to continue discussions with EPC contractors to reduce price and to adjust financial plans. While the development of the 154 MW Amaila Falls projects is based on the decision to shift from costly and imported fuel sources to using the abundant, domestic water potential, the generation expansion plan has to consider developing the power sector in the most economically efficient manner (i.e. least cost). Amaila Falls hydro project is expected to cover a significant proportion of the existing power demands in Guyana. As such, the characteristics of the Project must be established in light of the existing and future power system (total installed capacity and size of individual units, power system reliability and stability). This Report provides a description of the economic fundamentals, assumptions and results of the study conducted by Mercados Energéticos Consultores (ME) to achieve the objectives of the Terms of Reference. 2. ECONOMIC RATIONALE ME estimated the economic profitability of the project (on base case assumptions) and performed a cost-benefit analysis, calculating the net present value of the project with a benchmark discount rate of 12 %. The study covered the following key aspects: 1. Electricity demand forecast over a twenty year period Economic activity (GDP growth) was considered the main driver to explain demand growth. In addition, short run demand projections also contemplated other drivers to account for demand growth (existing customers, new additions to customer base through UAEP6, loss reduction, non-served energy associated to generation shortfall). 2. Least cost generation expansion plan 6 Unserved Areas Electrification Programme Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 22 The optimal investment schedule to supply the forecasted load was modeled for two different situations: • a generation expansion plan fully based on thermal power plants and • a generation expansion that includes Amaila Falls hydro project in Y 2014. A comparison between both expansion plans was performed to assess costs and benefits of Amaila Falls and to determine its economic rate of return: • The cost of the project is basically the power purchase agreement (PPA) between GPL and the developer that entitles the latter to receive a fixed annual payment for the energy delivered. • On the benefits side, the most important ones are GPL’s direct savings in fuel purchases, in O&M costs and in capital expenditures in new thermal facilities. In addition, the economic benefit of the reduction in green house gases emissions is discussed. Main assumptions for the optimal expansion plan are: crude oil prices scenario, expected demand growth and type of technology available for candidate projects in Guyana (in addition to Amaila Falls). 3. Competitiveness of Amaila Falls ME compared GPL’s supply cost and cost of self generation to discuss the competitiveness of the project in the short run. In the medium to long term, assuming crude oil prices of 75 USD / bbl, GPL’s average supply costs including Amaila Falls in its expansion plan are lower than the alternative expansion option (diesel-fired generators). 4. Risk analysis (Sensitivity analysis) Based on the cost benefit analysis developed for the Base Case, ME identified the main factors that negatively influence the economic rationale of the project: namely fuel prices and demand growth. 5. Review of existing studies (done by MWH) on the hydrology for the project Existing studies on the hydrology and project design were reviewed in order to verify the conclusions outlined by MWH and to assess possible design enhancements based on available field data. 3. PROJECT BACKGROUND 3.1. AMAILA FALLS PHYSICAL SETTING The Amaila Falls Hydroelectric Project is located on the Kuribrong River in west central Guyana, about 250 kilometers southwest of Georgetown. The dam site is at the confluence of the Amaila and Kuribrong Rivers. The Project would include a small storage reservoir created by two small dams constructed at the confluence of the Amaila and Kuribrong Rivers, at the top of Amaila Falls. The reservoir area is a heavily forested plateau with rock outcrops near the surface. The river drops about 60 meters at the falls and then continues through a series of rapids and smaller falls to the proposed powerhouse site. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 23 Figure 1: Location Map The Kuribrong River continues 90 kilometers downstream of the powerhouse site and feeds into the Potaro River, which then flows about 30 kilometers to its confluence with the Essequibo River. The Essequibo River crosses the coastal plain and drains to the ocean about 35 kilometers northwest from Georgetown. The Project would also include 296 kilometers of 230-kV, double-circuit transmission line to connect the Project with potential customers. 3.2. GUYANA POWER SECTOR OVERVIEW The electricity sector in Guyana is dominated by Guyana Power and Light (GPL), a vertically integrated government-owned utility with a monopolistic position on transmission and distribution, and a major stake in generation. GPL operates the Demerara and Berbice areas, where most of the country’s demand is concentrated. It is expected that the completion of the Sophia – Onverwagt transmission link by 2011 would realize the Demerara Berbice Interconnected System (DBIS). GPL owns and manages 142 MW of installed capacity (2009), all of which is based on thermoelectric plants with diesel-engine driven generators. A considerable proportion of GPL’s current power generation facilities are inefficient as the utility has resorted to the use of both own and rented high-cost small independent generation units in order to enhance generation capacity in some regions of the country. Electrification in Guyana is low both in terms of access and in terms of intensity of use relative to other countries in the region. Electrification is higher in coastal towns with a high industry concentration, there are vast areas of the country underserved. In fact, the Government of the Cooperative Republic of Guyana (GoG) has received financing from the Inter-American Development Bank (IDB) towards the cost of the Unserved Areas Electrification Programme (UAEP). The programme is jointly funded by the IDB, the GoG and GPL. The key objectives are to provide electricity to at least Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 24 30,000 households in what are classified as Unserved Areas, and to assess and reduce the distribution losses. Electricity provision in Guyana is affected by its high reliance on expensive imported oil and tariff-setting mechanisms (quarterly updated with fuel costs). Most of the installed generation capacity in Guyana is based on diesel-engine driven generators, exposing the sector to price shocks and the inherent volatility of the international oil markets. The electricity sector in Guyana suffers major losses at both distribution and commercialization activities, which are a major contributing factor to high tariffs. Losses at the distribution level account for up to 33 % of the energy generated (Source: GPL). At the commercial level, the utility is making efforts to enforce collection of bills, and to eradicate theft. GPL is currently undertaking a loss reduction programme aiming at reducing losses from its actual level to 20.7 % in a five year period (Source: GPL). Electricity in Guyana is also generated by a limited number of Independent Power Producers (IPPs, mainly sugar and mining companies). IPPs are mainly large corporate firms that generate power for their own needs and sell excess capacity to the national grid. Guysuco (Skeldon 30 MW co-generation facility) has started providing energy to the grid 25 weeks per year. Energy deliveries to the grid were 39 GWh during 2009 and 81 GWh is estimated for Y 2010 (Source: GPL). Deficiencies in power infrastructure and low reliability of service in Guyana may pose an important constraint for the development of the country. The lack of reliable infrastructure and services affect the development of the private sector by reducing its competitiveness and discouraging additional private investment. The poor reliability of electricity supply has placed a significant burden on companies in Guyana, which reduces their competitiveness. The development of physical infrastructure is critical for a sustainable economic growth and improvement on quality of life. According to the World Bank in its Guyana Investment Climate Assessment Report (2007), four aspects of the investment climate were mentioned in the group of top constraints: cost of financing, macroeconomic uncertainty, worker skills and education, and electricity. 3.2.1. SELF GENERATION The poor reliability of supply generates important losses for companies through lost revenues. The data from the World Bank (ICS 20077) indicated that while 100 % of large firms participating in the survey have their own power generation, the proportion of companies with such facilities along with the share of electricity generated internally decreases significantly with the size of the industry. This fact has been confirmed in the survey recently conducted among the most important self generators registered in the Guyana Energy Agency (GEA) (see Annex I). Key findings of the survey are: • It confirmed that self-supply of electricity in Guyana meets a significant proportion of the country’s electricity demand, although it is costly and generates economic inefficiencies. 7 ICS stands for Investment Climate Survey conducted by the World Bank in Y 2007. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 25 • The majority of the self generators are located along the East Bank of Demerara corridor which is an area in close proximity with the existing GPL grid. • The database of Guyana Energy Agency (GEA) contains about 622 entries. • Approximately 40 self generators were surveyed. Most of them utilize their generation equipment as load demand necessitates. A minority use them as standby units. • The results of the survey show that some 10.94 GWh is produced monthly by individual self generators. This represents an annual generation of 131 GWh (approximately 20 % of GPL’s gross demand). • The results of the survey may be considered a lower limit for annual self generation, given that only some of the data for the list of self generators has been gathered. 3.2.2. LINDEN AREA Linden Power Company (LPC) is another major customer, as the planned transmission line will be routed through Linden. Linden area is composed by a community of approximately 6,000 inhabitants and a mining company (Bauxite company), with a total consumption varying between 66 and 70 GWh-year, depending on the activity of the mining company. Presently, light diesel fuel is used for power generation in Linden. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 26 SECTION II: DEMAND FORECAST 1. ELECTRICITY DEMAND DRIVERS 1.1. MACROECONOMIC GROWTH The main driver to account for electricity demand growth is the economic activity (GDP) which explains the natural trend in demand growth. Electricity demand in Guyana is closely related to its export activity, mainly primary agricultural (sugar and rice) and mining (bauxite, gold) commodities. These exports account for around two thirds of Guyana’s GDP and are the traditional economic drivers. The manufacturing sector shows mixed performances and engineering and construction recently expanded. Lately there has been an effort to diversify Guyana’s productive base, especially in areas such as agriculture and the services sector. Domestic output is highly dependent on commodity prices. Although it has expanded for three consecutive years 2006, 2007 and 2008 (following growth rates of 5.1, 5.4 and 3.1 %, respectively), a slowdown is expected in 2009, mainly due to the decrease in sugar prices (Source: Ministry of Finance, Guyana). It’s worth noting that electricity generating capacity should be capable to flexibly incorporate commodity market variance and for it, reserve margins should be widened from current low levels. 1.2. EXTRA-TENDENCY GROWTH IN THE SHORT RUN Besides, in the short run, there are three factors that account for an extra tendency growth of electricity sales within GPL’s serving area. These factors are added to the projected electricity sales that result from the regression models as a function of GDP in the first four years of the study time horizon: • New connections under un-served areas electrification programmes and current construction boom: 9,900 new connections under electrification projects and 10,000 new households in served areas in the next four years (2010 – 2013) at an average specific consumption of 75 kWh per month per client. Source: GPL • Reduction in non-served energy due to present generation shortfall: lost sales due to power outages are estimated to be 1.3 % of total sales (4.9 GWh-year, 2009e). Source: GPL • Loss reduction programme at the distribution level: the five-year programme currently in place to replace defective meters and to reduce electricity theft is expected to diminish system losses from its present level of 33 % to 20.7 %. The expected cut down in technical and non technical losses per year is as follows (Source GPL): Year Technical Losses Non-technical Losses 2009 11.4 % 21.6 % 2010 10.6 % 19.4 % 2011 9.9 % 17.5 % 2012 9.3 % 15.7 % 2013 8.1 % 12.7 % Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 27 From Y 2013 onwards, losses remain constant at 20.8 %. In addition, it is expected that a portion of the loss reduction will increase sales and a portion will cut down demand, assuming a short run price elasticity of -0.2 (a 1 % price increase results in a 0.2 % reduction in electricity consumption). It’s worth mentioning that ME tested different econometric models to estimate the price elasticity for residential, commercial and industrial sectors in Guyana. In all cases, tariff was not a significant driver to explain demand evolution and econometric results were not robust, mainly due to insufficient number of historical data points. Therefore, ME adopted a benchmark approach to estimate price elasticity and assumed that consumer behavior in Guyana is similar to other countries in the region. Such benchmark analysis revealed that electricity demand is, in general terms, relative inelastic to price changes: regression models in other countries of Latin America and the Caribbean region8 give evidence of a price elasticity of -0.2 in the short run and -0.5 in the long run. 2. REGRESSION MODELS Conditioned to data availability, ME forecasted the electricity sales by type of customer as a function of global GDP9. For each sector, ME tested different functional forms for the regression models and selected those with the highest R-squared10 and the best statistical indicators: Type of customer Independent variable Functional form Residential Global GDP Exponential Commercial Global GDP Linear trend Industrial Global GDP Exponential Public Lightning Linear trend with an autorregresive term Regression parameters and statistical indicators are shown in the table below for each consumption sector: Dependent variable Residential consumption LOG(C_RES) Commercial consumption C_COM Industrial consumption LOG(C_IND) C_LP Public lightning 8 Variable LOG(GDP) C GDP C LOG(GDP) C TREND CE_AP(-1) C Coefficient 1.425 -0.455 16.113 -33150.55 2.190 -7.360 429.919 0.487 -564.001 t-Statistic 6.739 -0.248 6.271 -2.213 12.961 -5.027 3.742 2.883 -1.692 Prob. 0.0001 0.809 0.0001 0.054 0 0.0007 0.0072 0.024 0.135 R-squared 0.835 0.814 0.949 0.977 Chile, Mexico, Panama, Costa Rica, Paraguay, Colombia and Dominican Republic 9 Source: Bureau of Statistics, 1988 constant prices R squared is a statistical measure commonly used to express how well a regression line approximates real data points. 10 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 28 Where: LOG(C_RES): logarithm of residential customer’s consumption; LOG(GDP): logarithm of GDP; C: constant; C_COM: commercial customer’s consumption; LOG(C_IND): logarithm of industrial customer’s consumption; C_PL: public lightning consumption; C_PL(-1): public lightning consumption autorregresive term; TREND: linear tendency term Total demand elasticity to GDP growth is 1.75 (i.e. a 3.0 % GDP growth accounts for 5.2 % in demand growth). This elasticity varies among consumption sectors: 1.4 for residential customers and 2.2 for industrial users. It’s worth noting that the degree of confidence of econometric models increases with the number of real data points included in the regression to estimate model’s parameters. Guyana’s historical electricity sales series by type of customer are only available since Y 2000 (Source: GPL), which is considered a relative short period of time for a regression analysis, thus influencing the reliability of the results. 2.1. FORECAST OF THE INDEPENDENT VARIABLE (GDP) Once the econometric models were specified and its parameters estimated for each sector, ME envisaged a base case macroeconomic scenario to forecast GDP growth based on: • IADB, WB and CEPAL forecasts in the short run (2009 – 2011). • From Y 2011 onwards, ME defined a linear trend model with an autoregressive term to forecast GDP: Dependent Variable LOG(GDP) Variable TREND LOG(GDP(-1)) C Coefficient 0.003 0.904 0.760 t-Statistic 3.026 15.764 1.607 Prob. 0.005 0.000 0.119 R-squared 0.948 Where: LOG(GDP): logarithm of GDP; TREND: linear tendency term; LOG(GDP(-1)): logarithm of GDP autorregresive term; C: constant The projected GDP growth is shown in the table below: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 29 Figure 2: Forecasted GDP growth 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 GDP at factor cost G$M Growth rate% 5360 5270 -1.7% 5426 3.0% 5352 -1.4% 5474 2.3% 5537 1.2% 5500 -0.7% 5587 1.6% 5478 -2.0% 5759 5.1% 6066 5.3% 2008 6253 Year 3.1% 2009 6393 2.2% 2010 6572 2.8% 2011 6803 3.5% 2012 6996 2.8% 2013 7197 2.9% 2014 7405 2.9% 2015 7621 2.9% 2016 7845 2.9% 2017 – 2025 3.0% 2026 onwards 3.1% Sources: Bureau of Statistics & Ministry of Finance (historical figures), own elaboration based on CEPAL and on World Bank projections (forecasted trend) 2.2. ELECTRICITY DEMAND PROJECTION (GPL) With the above mentioned assumptions related to economic growth and extra-tendency factors in the short run, the forecasted total annual demand growth for GPL’s serving area is shown in the graph and table below: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 30 1600 15.0% 1400 12.0% 1200 9.0% GWh - year 1000 6.0% Total energy sales forecasted growth 800 3.0% GDP expected growth (independent variable) Forecasted total energy sales in GWh-year (with regression models by consumption sector) 600 0.0% 400 -3.0% 200 -6.0% 0 Energy sales / GDP annual growth rate Expected GDP growth and energy sales forecast -9.0% 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 Year Energy Sales: Historic Evolution (GWh-year) GDP historic evolution (annual growth) Energy sales: historic annual growth 2020 2022 2024 2026 2028 2030 2032 Energy sales forecast (GWh-year) Forecasted GDP Energy sales: forecasted growth Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 31 Year 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 Residential MWh 160364 174153 185080 188864 196551 204649 213122 222030 231378 241142 251414 262175 273448 285261 297585 310530 324069 338230 353045 368544 384723 401689 419444 437983 457386 477648 % 3.1% 8.6% 6.3% 2.0% 4.1% 4.1% 4.1% 4.2% 4.2% 4.2% 4.3% 4.3% 4.3% 4.3% 4.3% 4.4% 4.4% 4.4% 4.4% 4.4% 4.4% 4.4% 4.4% 4.4% 4.4% 4.4% Commercial MWh 64827 70401 74806 76399 79508 82744 86096 89574 93184 96902 100768 104758 108896 113176 117590 122164 126880 131752 136785 141983 147350 152905 158639 164540 170644 176941 % -7.8% 8.6% 6.3% 2.1% 4.1% 4.1% 4.1% 4.0% 4.0% 4.0% 4.0% 4.0% 4.0% 3.9% 3.9% 3.9% 3.9% 3.8% 3.8% 3.8% 3.8% 3.8% 3.8% 3.7% 3.7% 3.7% Industrial MWh 130691 141928 150809 158035 168022 178776 190289 202658 215932 230097 245329 261644 279148 297907 317926 339418 362396 387039 413396 441590 471751 504113 538745 575757 615369 657768 % 4.6% 8.6% 6.3% 4.8% 6.3% 6.4% 6.4% 6.5% 6.6% 6.6% 6.6% 6.7% 6.7% 6.7% 6.7% 6.8% 6.8% 6.8% 6.8% 6.8% 6.8% 6.9% 6.9% 6.9% 6.9% 6.9% Public Lighting MWh 6269 6807 7233 7830 8634 9437 10241 11045 11849 12653 13456 14260 15064 15868 16673 17476 18280 19085 19888 20692 21497 22301 23103 23907 24711 25514 % 19.8% 8.6% 6.3% 8.2% 10.3% 9.3% 8.5% 7.9% 7.3% 6.8% 6.3% 6.0% 5.6% 5.3% 5.1% 4.8% 4.6% 4.4% 4.2% 4.0% 3.9% 3.7% 3.6% 3.5% 3.4% 3.3% Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project Annual consumption MWh 362151 393290 417930 431128 452716 475607 499748 525307 552342 580793 610968 642837 676556 712212 749773 789588 831625 876106 923114 972808 1025319 1081007 1139931 1202187 1268110 1337871 % 1.7% 8.6% 6.3% 3.2% 5.0% 5.1% 5.1% 5.1% 5.1% 5.2% 5.2% 5.2% 5.2% 5.3% 5.3% 5.3% 5.3% 5.3% 5.4% 5.4% 5.4% 5.4% 5.5% 5.5% 5.5% 5.5% New connections MWh 4478 4478 4478 Total Annual Energy Sales MWh 362151 393290 417930 435606 457193 480084 499748 525307 552342 580793 610968 642837 676556 712212 749773 789588 831625 876106 923114 972808 1025319 1081007 1139931 1202187 1268110 1337871 % 1.7% 8.6% 6.3% 4.2% 5.0% 5.0% 4.1% 5.1% 5.1% 5.2% 5.2% 5.2% 5.2% 5.3% 5.3% 5.3% 5.3% 5.3% 5.4% 5.4% 5.4% 5.4% 5.5% 5.5% 5.5% 5.5% Technical Losses Non Technical Losses % 11.4% 11.4% 10.6% 9.9% 9.3% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% % 21.6% 21.6% 19.4% 17.5% 15.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% Annual Demand MWh 540524 587000 597042 619187 646935 673345 700924 736773 774691 814595 856917 901615 948908 998918 1051599 1107441 1166401 1228788 1294720 1364418 1438068 1516173 1598817 1686136 1778596 1876439 Growth rate % 8.60% 1.71% 3.71% 4.48% 4.08% 4.10% 5.11% 5.15% 5.15% 5.20% 5.22% 5.25% 5.27% 5.27% 5.31% 5.32% 5.35% 5.37% 5.38% 5.40% 5.43% 5.45% 5.46% 5.48% 5.50% 32 2.3. ELECTRICITY DEMAND IN LINDEN AREA As mentioned before, Linden Power Company (LPC) and Bauxite mining company are another major customers, as the planned transmission line can easily be routed through Linden. Linden area is composed by a community of approximately 6,000 inhabitants and the said mining company, with a total consumption varying between 66 and 70 GWh-year, depending on the activity of the mining company. It is assumed that current 66.5 GWh-year (2009e, Source: LPC) will evolve with macroeconomic growth (expected GDP). 2.4. SELF-GENERATION An independent consultant was engaged by National Investment and Commercial Investments Ltd (NICIL) and the Guyana Power and Light Inc (GPL) to conduct a survey to verify the level of self generation presently employed in Guyana, given the fact that every person has the right to self generate. See Annex I for further details (Survey Report). The objective of the Survey was to: • Conduct a field verification of the Self Generation database obtained from the Office of the Prime Minister • Update the said database • Establish the level of Self Generation that is taking place. The methodology used to execute the survey was to: • Review the database supplied by the GEA (Guyana Energy Agency) with the intention to identify the Top Twenty listed organizations. • Conduct site visits to the various operations at which self generation is predominant. That is mainly the so called “Top Twenty” industrial / commercial organisations which are self generating. • Conduct telephone interviews with other individuals and organisations listed in the database to verify the accuracy of the data. Main conclusions of the survey are the following • The database of Guyana Energy Agency (GEA) contains about 622 entries. • Approximately 40 self generators were surveyed. Most of them utilize their generation equipment as load demand necessitates. A minority use them as standby units. • Monthly self generation estimated at 10.94 GWh, that represents more than 20 % of GPL current demand. • The results of the survey may be considered a lower limit for annual self generation, given that only some of the data for the list of self generators has been gathered. • Self generation installed capacity is in excess of 47MW or 38 percent of GPL installed capacity. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 33 • Self generation is mostly used to secure reliable power supply • All companies surveyed are within grid areas • There are a number of firms which are interested in having GPL connections. • There are two clear groups of operators with GPL connections. The first group only use the GPL supply as a back up to their main source of supply and the second group obtains all or nearly all of their supply from GPL. • A number of firms will like to see the cost of power reduced and reliability and quality improved. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 34 SECTION III: COST-BENEFIT ANALYSIS FOR AMAILA FALLS PROJECT 1. LEAST COST EXPANSION PLAN While the development of the 154 MW Amaila Falls project is based on the decision to shift from costly and imported fuel sources to using the abundant, domestic water potential, the generation expansion plan has to consider developing the power sector in the most economically efficient manner. In order to estimate the economic profitability of Amaila Falls project, ME compared the expansion of the power generation capacity of Guyana with and without Amaila Falls project. ME determined the type of technology available for candidate projects in Guyana in addition to Amaila Falls project. For each technology selected, CAPEX and OPEX were estimated according to market prices of new equipment, typical O&M costs for each technology, efficiency and fuel price scenario. The simulation model OPTGEN was applied to identify the optimal (least cost) expansion plan for the power system in the long run. Two situations were considered: 1. Without Amaila Falls among the candidate projects: expansion of the generation capacity fully based on thermal power plants, typically medium speed engines or gas turbines, in both cases using liquid fuels (HFO, LFO) and 2. With Amaila Falls among the candidate projects: expansion of the generation capacity assuming that Amaila Falls hydro project begins commercial operation in Y 2014. From then onwards, if new capacity additions are needed, they will be thermal plants using liquid fuels. The objective function is to minimize the expected supply costs, including investment, operational costs and non-supplied energy cost; subject to an adequate reliability of the system’s operation (reserve margin): MIN TotalCosts[USD ] = t = 40 ∑ (CAPEX t =1 t + OPEX t ) ∗ (1 + i ) −t Subject to a reasonable level of non-supplied energy Where t each year of the evaluation period (t =1: 2009) CAPEX t [USD]: Capital Expenses of each year t OPEX t [USD]: i: Operational Expenses of each year t Economic rate of return The amount of un-served energy sets the quality standard. ME assumed a threshold of 1x10-3 of total demand (on average). New capacity additions are triggered in order to keep this quality standard. The simulation results for each alternative compute: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 35 • New capacity additions (size, time) and expected CAPEX • Expected dispatch of power plants and associated OPEX (fuel cost and O&M). • Generation reserve margin • Non-supplied energy • Supply costs The results attained for each capacity expansion situation are next compared to estimate the measurable benefits of Amaila Falls project: • Direct savings in fuel purchases for generation purposes • Direct savings in O&M of the thermal generation fleet • Direct savings in capital expenditures on new thermal facilities. • Carbon emissions reduction 2. KEY ASSUMPTIONS 2.1. DEMAND FORECAST It was already discussed in Section II of this Report. The following table summarizes the expected demand: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 36 Period 2009 - 2021 Demand Forecast GDP growth Total Sales GPL system T & D losses Year % 2009 2.2% 2010 2.8% 2011 2.8% 2012 2.8% 2013 2.9% 2014 2.9% 2015 2.9% 2016 2.9% 2017 3.0% 2018 3.0% 2019 3.0% 2020 3.0% 2021 3.0% GWh annual growth 393 418 6.3% 431 3.2% 453 5.0% 476 5.1% 500 5.1% 525 5.1% 552 5.1% 581 5.2% 611 5.2% 643 5.2% 677 5.2% 712 5.3% in % Technical 11.4% 10.6% 9.9% 9.3% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% Non-technical 21.6% 19.4% 17.5% 15.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 587 597 1.7% 619 3.7% 647 4.5% 673 4.1% 701 4.1% 737 5.1% 775 5.1% 815 5.2% 857 5.2% 902 5.2% 949 5.2% 999 5.3% 66 68 2.8% 70 2.8% 72 2.8% 74 2.9% 76 2.9% 79 2.9% 81 2.9% 83 3.0% 86 3.0% 88 3.0% 91 3.0% 94 3.0% 0.60 79 0.40 131 135 2.9% 139 3.0% 143 3.0% 148 3.0% 152 3.0% 157 3.0% 856 14.5% 947 10.6% 991 4.7% 1,037 4.7% 1,086 4.7% 1,138 4.7% 1,192 4.8% 1,249 4.8% Gross generation GPL system GWh annual growth Linden Power Company GWh Self generation switching to the grid GWh Total expected demand Expected demand growth GWh % 653 665 1.8% 689 3.6% 719 4.3% 748 4.0% MW MW 75 108 76 110 79 114 82 119 85 124 Average load Peak demand - - - - - 98 142 108 157 113 164 118 172 124 180 130 188 136 197 143 207 Period 2022 – 2053 (selected years) Demand Forecast GDP growth Total Sales GPL system T & D losses Year % 2022 3.0% 2023 3.0% 2024 3.0% 2025 3.0% 2030 3.1% 2035 3.1% 2040 3.1% 2045 3.1% 2050 3.1% 2053 3.1% GWh annual growth 750 5.3% 790 5.3% 832 5.3% 876 5.3% 1,140 5.5% 1,479 5.1% 1,901 5.1% 2,443 5.1% 3,140 5.1% 3,650 5.1% in % Technical 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% GWh annual growth 1,052 5.3% 1,107 5.3% 1,166 5.3% 1,229 5.3% 1,599 5.5% 2,073 5.1% 2,659 5.1% 3,412 5.1% 4,379 5.1% 5,086 5.1% Linden Power Company GWh 97 3.0% 100 3.0% 103 3.0% 106 3.0% 123 3.1% 143 2.9% 164 2.9% 190 2.9% 219 2.9% 238 2.9% Self generation switching to the grid GWh 161 3.0% 166 3.0% 171 3.0% 176 3.0% 205 3.1% 239 3.1% 278 3.1% 324 3.1% 377 3.1% 413 3.1% Total expected demand Expected demand growth GWh % 1,310 4.8% 1,373 4.9% 1,440 4.9% 1,511 4.9% 1,927 5.0% 2,454 4.8% 3,102 4.8% 3,926 4.8% 4,975 4.9% 5,737 4.9% Non-technical Gross generation GPL system Average load Peak demand MW MW 149 217 157 227 164 238 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 172 250 220 319 280 406 354 513 448 649 568 823 655 949 37 2.2. FUEL PRICES The variable cost of production of thermal power plants is largely based on the cost of fuel and plant’s efficiency and, in second place, on the operation and maintenance costs. In turn, the cost of fuel depends on crude oil price (WTI). LFO has historically been more expensive than HFO, as shown in the graph below (evolution of international prices of HFO (fuel oil #6), LFO (fuel oil # 2) and crude oil (WTI), 1998 – Aug 2009). WTI, HFO & LFO Historic Evolution 1998 - Aug 2009 Source of data: Energy Information Administration (www.eia.doe.gov) 170,0 160,0 150,0 140,0 130,0 120,0 USD / bbl 110,0 100,0 90,0 80,0 70,0 60,0 50,0 40,0 30,0 20,0 10,0 D ic -9 Ab 7 r-9 Ag 8 o9 D 8 ic -9 Ab 8 rAg 99 o9 D 9 ic -9 Ab 9 rAg 00 o0 D 0 ic -0 Ab 0 rAg 01 o0 D 1 ic -0 Ab 1 rAg 02 o0 D 2 ic -0 Ab 2 rAg 03 o0 D 3 ic -0 Ab 3 rAg 04 o0 D 4 ic -0 Ab 4 rAg 05 o0 D 5 ic -0 Ab 5 rAg 06 o0 D 6 ic -0 Ab 6 rAg 07 o0 D 7 ic -0 Ab 7 rAg 08 o0 D 8 ic -0 Ab 8 rAg 09 o09 - Month - Year EIA - FO 6 EIA - Diesel Oil (FO 2) WTI Therefore, ME forecasted the future international prices for liquid fuels as a linear function of crude oil prices, with the following regression parameters: HFO (in USD / bbl, FOB) = +1.684 + 0.726 x Crude Oil Price (USD / bbl) LFO (in USD / bbl, FOB) = -3.556 + 1.269 x Crude Oil Price (USD / bbl) Foreign freight and insurance is added to the forecasted international prices (5.8 USD / bbl). For the Base Case, ME adopted a crude oil price of 75 USD / bbl, consistent with the latest projections (June 2009) of the World Bank. The table shows the forecasted fuel prices: Crude Oil (USD / bbl) FOB Freight CIF FOB Freight CIF 75 56.1 5.8 61.9 91.6 5.8 97.4 2.3. HFO (USD / bbl) LFO (USD / bbl) TYPE OF TECHNOLOGY TO EXPAND THE POWER SYSTEM Forecasts of electricity supply costs generally assume that, in the long run, the market will be in equilibrium and the long run marginal cost of the system will reflect the cost of Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 38 supplying an additional unit of energy with the most competitive available technology for such market (i.e. at minimum cost). Subject to fuel availability, the most significant factors influencing costs include fixed capital costs, variable operating costs (fuel and O&M costs) and the financial structure (discount rate). It also depends on the expected load factor of the new entry technology. Although the most common expansion technology adopted in Guyana in recent years has been bunker-fired internal combustion engines, it was necessary to verify, given the assumed evolution of fuel prices in the future, if this was the most competitive expansion technology in the long run. The most competitive expansion technology is defined as the one that minimizes the long run marginal cost of the system, i.e. the total cost (CAPEX and OPEX) to satisfy an additional unit of demand. Based on fuel availability in Guyana, ME selected two alternative technologies to estimate the long run marginal cost of Guyana’s power system: • HFO medium speed engines • Gas turbines using LFO For each technology selected as potential candidate to expand the generating capacity, ME estimated its CAPEX and OPEX according to market prices of new equipment, typical O&M costs for each technology, efficiency and fuel prices scenario. In both cases, ME selected a 7 MW capacity power unit, that is considered suitable for the demand size and annual growth of Guyana Power System. To compute capital expenditures (CAPEX) in thermal power units, it is assumed that they will be developed as private sector projects. Thus, it was assumed the private investor will expect a rate of return on equity of 16.07 % (which was estimated using the WACC method). The main characteristics adopted for each technology to compute the long run marginal cost (LRMC) are shown in the table below: Parameter HFO medium speed engines Gas turbines using LFO Investment Cost 1,100 USD / kW 450 USD / kW Return on equity 16.07 % 16.07 % Repayment period 10 years 10 years O&M 0.9 ¢USD / kWh 0.45 ¢USD / kWh Type of fuel Heavy fuel oil Light fuel oil Fuel cost on site 61.9 USD / bbl 97.4 USD / bbl Gross capacity 7 MW 7 MW 40 % 44 % 2,158.9 kCal / kWh 1,932 kCal / kWh 56.4 Gal / MWh 55 Gal / MWh 70 % 70 % Heat rate Expected dispatch Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 39 The optimal technology for the new capacity additions is the one that satisfies the leastcost principle. HFO medium speed engines is the favored expansion technology for relative high dispatch factors (see graph below). The long run marginal cost (includes CAPEX and OPEX) for this technology is around 13.0 – 14.0 ¢USD / kWh, assuming a crude oil price of 75 USD / bbl. Long run marginal cost of thermal expansion HFO-fired combustion engines vs LFO-fired gas turbines 28.0 in cUSD / kWh 26.0 24.0 22.0 20.0 18.0 16.0 14.0 12.0 0% 20% 40% 60% 80% 100% 120% Dispatch factor Engine Gas turbine The competitiveness of HFO engines increases when crude oil prices increase, (because the spread between HFO and LFO prices also raises). 2.4. COSTS OF AMAILA FALLS PROJECT The cost breakdown of the project was taken from Sithe’s financial model and it constitutes an input for ME’s cost-benefit analysis: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 40 CAPITAL COST ASSUMPTIONS EPC EPC 479,000 479,000 Repayment of Bridge loan Spare Parts / Startup Insurance Development Company Expenses, Manag Operator Labor Admin. Expenses Developers Bank's Legal Counsel Legal Counsel Owner's Engineer Lender's Engineer O&M Training Working Capital Debt Service Reserve 7,234 5,000 12,000 3,071 2,245 12,000 2,000 3,000 6,000 3,000 1,500 1,673 43,206 CAPEX Before Financing Fees & IDC 580,929 Interest During Construction Commitment Fee Upfront + Appraisal Fee Development Fee to Sithe Capital Costs incl tranche 1a Transmission Line and Substations Interest During Construction 1b Commitment Fee 1b Upfront + Appraisal Fee 1b 42,243 5,408 7,331 13,032 648,943 0 2,678 0 0 Operating Expenses: Fixed O&M Local: Labor Bank Fees Chemicals Environmental Occupational safety Spare Parts Utilities and Other Operating Routine equipment maintenance Scheduled maintenance Equipment mods & replacements Business Insurance G&A Expenses Fixed O&M US: Routine equipment maintenance Labor Scheduled Maintenance Equipment mods & replacements Other Other Other Other Other Total Fixed O&M: Variable O&M: Chemical and Non-Fuel Consumables Water Utilities and Other Operating Equipment Maintenance (excluding LTSA) Maintenance Reserve Transmission Tariff (TUST + TUSD) O&M Costs Equity Insurance Total Variable O&M: Total O&M Expense: $ $ $ $ $ $ $ $ $ $ $ $ 755 75 3 109 94 196 91 91 62 21 2,000 1,089 $ $ $ $ $ 823 149 559 190 0 0 0 0 $6,307 $/MWh $0 0 0 0 0 0.00 0.00 % of Equity 1.5% $6,307 651,621 As indicated by the Client, the power purchase agreement between GPL and the developer will consist of a fixed annual payment of 105,000 k USD. 3. LEAST COST EXPANSION PLAN As already mentioned in previous sections, in order to estimate the economic profitability of Amaila Falls project, ME compared the expansion of Guyana’s power generation capacity with and without Amaila Falls project and estimated the benefits of the hydro project as the sum of: • Direct savings in fuel purchases, • Direct savings in O&M costs and • Direct savings in capital expenditures (in new thermal facilities). Carbon emission reduction was also estimated as part of total project’s benefits, assuming a CER of 10.4 USD / ton CO2 (Source: Pointcarbon). However, it’s worth noting that, in principle, Amaila Falls would not be elegible to earn carbon credits because its size exceeds 20 MW. However, UN is currently reviewing the elegibility conditions for hydropower plants to include larger plants as long as Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 41 environment and local communities are preserved. The optimal (least cost) investment schedule to supply the forecasted load was modeled for two different situations: 1. Generation capacity expansion fully based on thermal power plants (selected technology was bunker-fired medium speed engines) and 2. Generation capacity expansion considering that Amaila Falls hydro project begins its commercial operation in Y 2014. From then onwards, the selected expansion technology, if needed, is bunker-fired engine. The model results for each alternative include: new capacity additions (size, time) and expected CAPEX, expected dispatch of power plants and associated OPEX (fuel cost and O&M) and generation reserve margin. 3.1. NEW GENERATING CAPACITY The size and timing of the new capacity additions necessary to meet the forecasted load subject to a given quality threshold11 are shown in the graphs below, for each expansion modeled: Guyana: Supply & Demand Balance Generation Capacity Expansion: Option # 1 (100 % Thermal) 130% 680 640 120% 600 21 560 28 21 440 in MW 360 320 280 240 200 120 21 90% 28 400 160 100% 28 480 21 - 34% 32% - 14 7 7 14 14 14 14 14 21 14 80% 21 70% 60% 50% 40% 30% 42 7 - 26% 23% 23% 22% 19% 80 7 14 14 21 21 28% 28% 26% 26% 29% 28% 27% Cumulative New Thermal Adds (y - 1) Annual New Thermal Additions Reserve Margin 2037 2036 2035 2034 2033 2032 2031 2030 2029 2028 2027 2026 2025 2024 2023 2022 2021 2020 2019 2018 2017 2016 2015 0% 2014 2012 2011 2010 2009 2013 7% Existing Thermal 20% 10% 40 - Reserve margin in % 520 110% Peak Demand It’s worth noting that capacity additions meet the expected demand growth, while keeping the system’s reliability (reserve margin). The resulting reserve margin (Installed Capacity / Peak Demand) is approximately 30 %. 11 unserved demand less than 1 x 10–3 of total demand Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 42 Guyana: Supply & Demand Balance Generation Capacity Expansion: Option #2 Amaila Falls begins operations in Y 2014 130% 680 640 120% 600 21 560 28 21 92% 440 in MW 360 74% 320 66% 280 - - - 59% - 240 90% - - - - 14 14 14 21 14 21 21 14 80% 21 70% 60% 50% 52% 40% 45% 200 120 21 28 400 160 100% 28 480 - 34% 32% 38% 7 - 30% 32% 28% 28% 26% 26% 22% 19% 80 29% 28% 27% 2037 2036 2035 2034 2033 2032 2031 2030 2029 2028 2027 2026 2025 2024 2023 2022 2021 2020 2019 2018 2017 2016 2015 0% 2014 2012 2011 2010 2013 7% 2009 20% 10% 40 - Reserve margin in % 520 110% Amaila Falls (@delivery point) Existing Thermal Cumulative New Thermal Adds (y - 1) Annual New Thermal Additions Reserve Margin Peak Demand As can be seen in the graph, the addition of Amaila Falls by Y 2014 introduces a (temporary) excess of installed capacity. Reserve margin peaks and gradually decreases until Y 2022 when it falls below the target value and new thermal generation capacity is added to the system. In the long run there exist no differences in annual capacity additions between both expansion options. 3.2. EXPECTED DISPATCH OF POWER PLANTS The following graphs show the expected dispatch of power plants for each expansion option analyzed (see Annex I Model’s output (generation balance): Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 43 2,900 2,800 2,700 2,600 2,500 2,400 2,300 2,200 2,100 2,000 1,900 1,800 1,700 1,600 1,500 1,400 1,300 1,200 1,100 1,000 900 800 700 600 500 400 300 200 100 - Expected dispatch of new thermal facilities Expected Guysuco energy deliveries to the grid 20 37 20 36 20 34 20 35 20 32 20 33 20 31 20 29 20 30 20 27 20 28 20 26 20 25 20 23 20 24 20 21 20 22 20 20 20 18 20 19 20 16 20 17 20 14 20 15 20 09 20 12 20 13 Expected dispatch of existing thermal facilities 20 10 20 11 GWh per year Guyana Power System Expected Dispatch of Power Plants Option #1 Thermal expansion Expected dispatch of new thermal facilities Guysuco energy deliveries to the grid 20 36 20 37 20 34 20 35 20 33 20 31 20 32 20 29 20 30 20 28 20 27 20 25 20 26 20 23 20 24 20 22 20 20 20 21 20 18 20 19 Amaila Mean Energy Production 20 16 20 17 20 14 20 15 20 12 20 13 Expected dispatch of existing thermal facilities 20 11 2900 2800 2700 2600 2500 2400 2300 2200 2100 2000 1900 1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 20 09 20 10 GWh per year Guyana Power System Expected Dispatch of Power Plants Option #2 with Amaila Amaila Falls’s energy production is expected to meet base load, thermal units will be dispatched as needed to meet peak demand. It should be mentioned that, although Amaila Falls’s mean energy production may be higher than expected demand in the early years of the project, Amaila’s energy output Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 44 is subject, by definition, to hydro volalitility. Thus, there are some months of the year (during the dry season) when thermal plants need to be dispatched to meet the portion of demand load that can not be met by Amaila’s production. This is the reason why thermal dispatch is not null even in the time period when Amaila’s mean energy production is larger than expected demand. Amaila’s expected average energy production (983 GWh) is well-matched with expected demand growth driven by existing GPL / Linden customers; and the addition of 131 GWh-year of self generation as of 2014. As of Y 2022 increasing amounts of thermal generation are needed, on top of Amaila mean energy production, to meet expected demand and to keep a reasonable reserve margin in the system. 4. COST-BENEFIT ANALYSIS 4.1. COST STREAM Based on Sithe’s financial model, ME assumed a fixed annual payment for Amaila Falls energy production of 105,000 k USD during 20 years, regardless the amount of energy delivered and / or taken by the off-takers. 4.2. BENEFIT STREAM Once determined the necessary new capacity additions to meet expected load, total supply costs (CAPEX and OPEX) for each expansion option were estimated. The economic benefits of the project were identified and measured, by category, over the study time horizon (40 years): • Direct savings in fuel consumption • Direct savings in O&M costs of thermal facilities • Direct savings in capital expenditures in new thermal units. • Carbon emissions reduction The benefit stream was then computed as the sum of the four categories recognized. 4.2.1. DIRECT SAVINGS IN FUEL CONSUMPTION In estimating the avoided costs in fuel consumption, it has been assumed the following parameters: Average efficiency existing generation fleet: 34 % Average efficiency new thermal facilities: 40 % Fuel costs: HFO: 61.9 USD / bbl on site LFO 97.4 USD / bbl on site Generation mix progresses from its current 70 / 30 HFO / LFO towards 100 % HFO. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 45 Amaila Falls would significantly reduce the imports of liquid fuels for generation purposes. Avoided costs in fuel consumption for generation purposes are in the range of 80,000 to 85,000 thousand dollars per year. These direct savings represent approximately 68 % of total economic benefits considered. The following graph shows fuel costs with and without Amaila Falls hydro project: Fuel Costs with Amaila vs Thermal Expansion 225,000 200,000 175,000 k USD 150,000 125,000 100,000 75,000 50,000 25,000 Fuel Costs - 100 % Thermal Expansion 4.2.2. 2037 2035 2036 2033 2034 2031 2032 2029 2030 2027 2028 2025 2026 2023 2024 2021 2022 2019 2020 2017 2018 2015 2016 2013 2014 2011 2012 2009 2010 - Fuel Costs with Amaila Falls DIRECT SAVINGS IN O&M OF THERMAL GENERATION FLEET In estimating the avoided costs in 0&M expenses, it has been assumed the following parameters: O&M thermal facilities (includes lube consumption): 0.9 ¢USD / kWh O&M, Insurance hydro plant (source: financial model): 0.6 ¢USD / kWh Direct savings in O&M costs are in the range of 2,300 to 2,500 thousand USD per year, representing around 2 % of total economic benefits identified. 4.2.3. DIRECT SAVINGS IN CAPITAL EXPENDITURES IN NEW THERMAL FACILITIES In estimating the direct savings in capital expenditures in new thermal generators, it has been assumed the following parameters: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 46 Capacity 7 MW Investment cost 1,100 USD / kW Return on equity 16.07 % Repayment period 10 years Efficiency 40 % Expected dispatch 0.6 – 0.7 Direct savings in annual payments for new thermal facilities are approximately 30,000 thousand dollars per year, accounting for 24 % of total economic benefits. 4.2.4. CARBON EMISSIONS REDUCTION Finally, to estimate the carbon emissions reduction the following parameters were considered: Fuel option - Emission Factor CER kg CO2 / kg diesel USD / ton CO2 3.07 10.4 Source: Pointcarbon Benefits from carbon credits are estimated in 6,600 thousand dollars per year (approx. 5 % of total benefits identified). As already mentioned, it’s worth noting that, in principle, Amaila Falls would not be elegible to earn carbon credits because its size exceeds 20 MW. However, UN is currently reviewing the elegibility conditions for hydropower plants to include larger plants, as long as environment and local communities are preserved. Moreover, Denmark has recently approved a 81 MW Chinese hydro project as CDM, awaiting to obtain carbon credits. The project will now seek for UN’s approval (Source: PointCarbon). 4.3. COSTS AND BENEFITS STREAM Amaila’s fixed costs are evenly distributed over 20 years (PPA is a fixed annual payment of 105,000 k USD) while Amaila’s benefits are mainly concentrated on medium to long term (this is variable and depends on expected market development and oil prices). Amaila project brings structural benefits to the power system: a generation mix hydro – thermal is better to hedge risks (oil prices volatility) than a system that entirely relies on thermal plants. Cost-benefit stream is shown in the graph below: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 47 Amaila Falls Project: Costs and Benefits Stream 160,000 Savings in O&M costs Carbon credits 140,000 120,000 Savings in CAPEX (thermal units) 80,000 60,000 Savings in liquid fuel costs 40,000 20,000 2037 2036 2035 2034 2033 2032 2031 2030 2029 2028 2027 2026 2025 2024 2023 2022 2021 2020 2019 2018 2017 2016 -20,000 2015 2014 in thousand US dollars per year 100,000 -40,000 Fixed annual payment (PPA): -105,000 k USD -60,000 -80,000 -100,000 -120,000 Savings in Fuel Costs 4.4. Savings in CAPEX annual payments Savings in O&M Expenses Carbon Credits Total Costs NET PRESENT VALUE OF THE PROJECT AND ECONOMIC RATE OF RETURN Based on the costs and benefits identified, ME computed the net present value of the project, using the benchmark discount rate of 12 %. Under the set of assumptions and economic fundamentals described along this document, the economic indicators of the project are the following: NPV (kUSD) (@ 12%) ERR Benefit - Cost Ratio BCR 186,886 83% 0.70 BCR= NPV (Benefits) / NPV (Costs) ERR=Economic Rate of Return The annual net cash flow of the project (Costs – Benefits) is shown below: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 48 Net Cash Flow (Benefits minus Costs) 27,500 25,000 22,500 in thousand US dollars per year 20,000 17,500 15,000 12,500 10,000 7,500 5,000 2,500 2033 2032 2031 2030 2029 2028 2027 2026 2025 2024 2023 2022 2021 2020 2019 2018 2017 2016 2015 -2,500 2014 - -5,000 -7,500 Cash Flow GPL’s generation expenses in the first year of the time horizon are higher with Amaila than without Amaila. The rest of the years benefits outweigh costs. The cost differential in the first year is reduced if one assumes a more aggressive market expansion (self generation, Linden) and / or higher crude oil prices than considered in the Base Case (See Section V Sensitivity Analysis). The following table shows the costs and benefits stream 2009 – 2053. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 49 Period 2009 - 2017 COST-BENEFIT ANALYSIS FOR AMAILA FALLS PROJECT MAIN ASSUMPTIONS Crude Oil Price (WTI) Demand Forecast GDP growth Total Sales GPL system T & D losses Year USD / bbl 2009 75 2010 75 2011 75 2012 75 2013 75 2014 75 2015 75 2016 75 2017 75 Year % 2009 2.2% 2010 2.8% 2011 2.8% 2012 2.8% 2013 2.9% 2014 2.9% 2015 2.9% 2016 2.9% 2017 3.0% GWh annual growth 393 418 6.3% 431 3.2% 453 5.0% 476 5.1% 500 5.1% 525 5.1% 552 5.1% 581 5.2% in % Technical 11.4% 10.6% 9.9% 9.3% 8.1% 8.1% 8.1% 8.1% 8.1% Non-technical 21.6% 19.4% 17.5% 15.7% 12.7% 12.7% 12.7% 12.7% 12.7% Gross generation GPL system GWh annual growth 587 597 1.7% 619 3.7% 647 4.5% 673 4.1% 701 4.1% 737 5.1% 775 5.1% 815 5.2% Linden Power Company GWh 66 68 2.8% 70 2.8% 72 2.8% 74 2.9% 76 2.9% 79 2.9% 81 2.9% 83 3.0% Self generation switching to the grid GWh 0.60 79 0.40 131 135 2.9% 139 3.0% Total expected demand Expected demand growth GWh % 653 665 1.8% 689 3.6% 719 4.3% 748 4.0% 856 14.5% 947 10.6% 991 4.7% 1,037 4.7% MW MW 75 108 76 110 79 114 82 119 85 124 Average load Peak demand - - - - - 98 142 108 157 113 164 118 172 -105,000 -105,000 -105,000 -105,000 AMAILA FALLS COSTS PPA (fixed annual payment) k USD ECONOMIC BENEFITS Savings in Operating Costs Fuel Consumption Prices HFO (includes freight) LFO (includes freight) Generation mix Year 2009 2010 2011 2012 2013 2014 2015 2016 2017 USD / bbl USD / bbl 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61% 39% 70% 30% 70% 30% 80% 20% 82% 18% 83% 18% 85% 15% 86% 14% 86% 14% HFO LFO Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 Savings in Fuel Costs O&M Expenses O&M unit costs thermal engines O&M Amaila Falls bbl k USD bbl k USD 980,214 932,207 970,598 1,008,652 1,054,088 1,170,802 1,287,132 1,348,058 1,403,107 75,331 67,657 70,443 68,231 70,265 77,756 83,755 87,022 90,427 k USD USD / MWh USD / MWh 980,214 932,207 970,598 1,008,652 1,054,088 - 5,650 50,893 86,206 75,331 67,657 70,443 68,231 70,265 - 368 3,285 5,556 - - - - - 77,756 83,387 83,737 84,872 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 k USD k USD 5,530 5,530 5,259 5,259 5,476 5,476 5,744 5,744 6,000 6,000 6,976 5,219 7,792 5,566 8,188 5,935 8,605 6,300 PPA Guysuco Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 k USD k USD 4,337 4,337 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 4,760 9,007 9,007 9,007 9,007 9,007 9,007 Savings in O&M Expenses k USD Total Savings in Operating Costs Savings in Capital Expenditures in Thermal Plants Year Investment Cost USD / kW % Return on capital (assumes private inve Repayment period years Module MW New thermal capacity additions per year Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 Fuel option - Emission Factor Carbon bonds price Reduction in Fuel Consumption Reduction in CO2 tonnes tonnes GHG Emissions Reduction k USD TOTAL ECONOMIC BENEFITS NET CASH FLOW - - - 6,005 2,226 2,253 2,305 - - - 83,761 85,613 85,990 87,176 2009 2010 2011 2012 2013 MW-year MW-year - - - 7 7 k USD k USD - - - 1,597 1,597 Year kg CO2 / kg diesel USD / t - 2014 2015 42 - 21 - 1,597 1,597 11,181 1,597 9,584 2016 2017 1,100 16% 10 7 Savings in CAPEX annual payments GHG Emissions Reduction - - - - - - - 2009 2010 2011 2012 2013 2014 7 14 - 15,973 1,597 17,570 1,597 20,765 1,597 14,376 15,973 19,168 2015 - 2016 2017 3.07 10.43 k USD - - - -0 -0 -0 -0 180,123 552,979 - - - -0 -0 5,768 6,313 6,390 6,487 - - - -0 -0 99,112 106,302 108,353 112,831 -5,888 1,302 3,353 7,831 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 197,151 605,254 199,564 612,661 202,600 621,983 50 Period 2018 - 2026 COST-BENEFIT ANALYSIS FOR AMAILA FALLS PROJECT MAIN ASSUMPTIONS Crude Oil Price (WTI) Demand Forecast GDP growth Total Sales GPL system T & D losses Year USD / bbl 2018 75 2019 75 2020 75 2021 75 2022 75 2023 75 2024 75 2025 75 2026 75 Year % 2018 3.0% 2019 3.0% 2020 3.0% 2021 3.0% 2022 3.0% 2023 3.0% 2024 3.0% 2025 3.0% 2026 3.1% GWh annual growth 611 5.2% 643 5.2% 677 5.2% 712 5.3% 750 5.3% 790 5.3% 832 5.3% 876 5.3% 923 5.4% in % Technical 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% GWh annual growth 857 5.2% 902 5.2% 949 5.2% 999 5.3% 1,052 5.3% 1,107 5.3% 1,166 5.3% 1,229 5.3% 1,295 5.4% Linden Power Company GWh 86 3.0% 88 3.0% 91 3.0% 94 3.0% 97 3.0% 100 3.0% 103 3.0% 106 3.0% 109 3.1% Self generation switching to the grid GWh 143 3.0% 148 3.0% 152 3.0% 157 3.0% 161 3.0% 166 3.0% 171 3.0% 176 3.0% 182 3.1% Total expected demand Expected demand growth GWh % 1,086 4.7% 1,138 4.7% 1,192 4.8% 1,249 4.8% 1,310 4.8% 1,373 4.9% 1,440 4.9% 1,511 4.9% 1,585 4.9% Non-technical Gross generation GPL system Average load Peak demand MW MW 124 180 130 188 136 197 143 207 149 217 157 227 164 238 172 250 181 262 -105,000 -105,000 -105,000 -105,000 -105,000 -105,000 -105,000 -105,000 -105,000 AMAILA FALLS COSTS PPA (fixed annual payment) k USD ECONOMIC BENEFITS Savings in Operating Costs Fuel Consumption Prices HFO (includes freight) LFO (includes freight) Generation mix Year 2018 2019 2020 2021 2022 2023 2024 2025 2026 USD / bbl USD / bbl 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 87% 13% 89% 11% 89% 11% 89% 11% 91% 9% 91% 9% 93% 7% 93% 7% 93% 7% bbl k USD bbl k USD 1,471,767 k USD HFO LFO Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 Savings in Fuel Costs O&M Expenses O&M unit costs thermal engines O&M Amaila Falls USD / MWh USD / MWh 1,535,190 1,612,524 1,685,181 1,762,496 1,845,258 1,933,409 2,027,456 2,118,201 94,730 97,036 101,924 106,516 109,665 114,814 118,392 124,151 129,708 124,573 181,473 243,363 293,850 329,687 415,171 505,191 600,174 700,286 8,018 11,470 15,382 18,574 20,514 25,832 30,935 36,752 42,882 86,712 85,565 86,541 87,943 89,151 88,982 87,457 87,399 86,826 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 k USD k USD 9,045 6,688 9,509 7,128 9,998 7,596 10,514 8,061 11,057 8,517 11,630 9,090 12,233 9,693 12,869 10,329 13,540 11,000 PPA Guysuco Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 k USD k USD 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 Savings in O&M Expenses k USD Total Savings in Operating Costs Savings in Capital Expenditures in Thermal Plants Year Investment Cost USD / kW Return on capital (assumes private inv % Repayment period years Module MW New thermal capacity additions per year Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 Fuel option - Emission Factor Carbon bonds price Reduction in Fuel Consumption Reduction in CO2 tonnes tonnes GHG Emissions Reduction k USD TOTAL ECONOMIC BENEFITS NET CASH FLOW 2,402 2,453 2,540 2,540 2,540 2,540 2,540 88,944 90,396 91,691 91,522 89,997 89,939 89,366 2018 2019 2020 2021 2022 2023 2024 2025 2026 7 14 - 14 - 14 14 14 14 14 14 21 21 MW-year MW-year - k USD k USD 22,362 1,597 25,557 1,597 27,154 1,597 30,349 1,597 33,543 1,597 36,738 4,792 39,932 7,986 43,127 11,181 47,919 15,973 20,765 23,959 25,557 28,751 31,946 31,946 31,946 31,946 31,946 Year kg CO2 / kg diesel USD / t 2,381 87,946 1,100 16% 10 7 Savings in CAPEX annual payments GHG Emissions Reduction 2,357 89,070 7 2018 14 - 2019 - 2020 2021 2022 2023 2024 2025 2026 3.07 10.43 207,261 636,290 k USD 208,264 639,371 210,640 646,665 214,051 657,136 220,432 676,727 220,013 675,441 219,726 674,558 219,582 674,116 218,141 669,692 6,637 6,669 6,745 6,854 7,058 7,045 7,036 7,031 6,985 116,471 118,574 121,245 126,001 130,695 130,512 128,978 128,916 128,297 11,471 13,574 16,245 21,001 25,695 25,512 23,978 23,916 23,297 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 51 Period 2027 - 2035 COST-BENEFIT ANALYSIS FOR AMAILA FALLS PROJECT MAIN ASSUMPTIONS Crude Oil Price (WTI) Demand Forecast GDP growth Total Sales GPL system T & D losses Year USD / bbl 2027 75 2028 75 2029 75 2030 75 2031 75 2032 75 2033 75 2034 75 2035 75 Year % 2027 3.1% 2028 3.1% 2029 3.1% 2030 3.1% 2031 3.1% 2032 3.1% 2033 3.1% 2034 3.1% 2035 3.1% GWh annual growth 973 5.4% 1,025 5.4% 1,081 5.4% 1,140 5.5% 1,202 5.5% 1,268 5.5% 1,338 5.5% 1,407 5.1% 1,479 5.1% in % Technical 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% GWh annual growth 1,364 5.4% 1,438 5.4% 1,516 5.4% 1,599 5.5% 1,686 5.5% 1,779 5.5% 1,876 5.5% 1,972 5.1% 2,073 5.1% Linden Power Company GWh 112 3.1% 116 3.1% 119 3.1% 123 3.1% 127 3.1% 131 3.1% 135 3.1% 139 2.9% 143 2.9% Self generation switching to the grid GWh 187 3.1% 193 3.1% 199 3.1% 205 3.1% 211 3.1% 218 3.1% 225 3.1% 232 3.1% 239 3.1% Total expected demand Expected demand growth GWh % 1,664 5.0% 1,747 5.0% 1,835 5.0% 1,927 5.0% 2,024 5.1% 2,127 5.1% 2,236 5.1% 2,342 4.8% 2,454 4.8% Non-technical Gross generation GPL system Average load Peak demand MW MW 190 275 199 289 209 304 220 319 231 335 243 352 255 370 -105,000 -105,000 -105,000 -105,000 -105,000 -105,000 -105,000 267 388 280 406 - - AMAILA FALLS COSTS PPA (fixed annual payment) k USD ECONOMIC BENEFITS Savings in Operating Costs Fuel Consumption Prices HFO (includes freight) LFO (includes freight) Generation mix Year 2027 2028 2029 2030 2031 2032 2033 2034 2035 USD / bbl USD / bbl 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 93% 7% 93% 7% 94% 6% 94% 6% 94% 6% 94% 6% 94% 6% 94% 6% 94% 6% bbl k USD bbl k USD 2,224,799 2,328,772 2,440,327 2,569,007 2,696,255 2,822,829 2,967,920 3,109,691 3,250,374 136,235 142,602 148,230 156,046 163,775 171,464 180,277 188,888 197,433 805,835 917,081 1,034,710 1,158,848 1,289,687 1,427,867 1,573,727 1,716,791 1,866,848 49,345 56,157 62,850 70,390 78,338 86,731 95,591 104,281 113,396 k USD 86,890 86,445 85,380 85,656 85,437 84,732 84,686 84,607 84,038 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 HFO LFO Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 Savings in Fuel Costs O&M Expenses O&M unit costs thermal engines O&M Amaila Falls USD / MWh USD / MWh Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 k USD k USD 14,248 11,708 14,993 12,453 15,782 13,242 16,614 14,074 17,491 14,951 18,417 15,877 19,394 16,854 20,353 17,813 21,359 18,819 PPA Guysuco Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 k USD k USD 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 Savings in O&M Expenses k USD Total Savings in Operating Costs Savings in Capital Expenditures in Thermal Plants Year Investment Cost USD / kW Return on capital (assumes private inv % Repayment period years Module MW New thermal capacity additions per year Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 MW-year MW-year Savings in CAPEX annual payments Year Fuel option - Emission Factor Carbon bonds price kg CO2 / kg diesel USD / t Reduction in Fuel Consumption Reduction in CO2 tonnes tonnes GHG Emissions Reduction k USD TOTAL ECONOMIC BENEFITS NET CASH FLOW 2,540 2,540 2,540 2,540 2,540 2,540 2,540 2,540 88,985 87,920 88,196 87,977 87,272 87,226 87,147 86,578 2027 2028 2029 2030 2031 2032 2033 2034 2035 14 14 21 21 21 21 14 14 21 21 28 28 21 21 21 21 28 28 51,113 19,168 55,905 23,959 60,697 28,751 63,892 31,946 68,684 36,738 75,073 43,127 79,865 47,919 84,656 52,711 91,046 59,100 31,946 31,946 31,946 31,946 31,946 31,946 31,946 31,946 31,946 1,100 16% 10 7 k USD k USD GHG Emissions Reduction 2,540 89,430 2027 2028 2029 2030 2031 2032 2033 2034 2035 3.07 10.43 218,302 670,188 k USD 217,183 666,752 216,249 663,883 216,948 666,029 216,395 664,333 214,610 658,851 214,491 658,488 214,292 657,877 212,850 653,450 6,990 6,954 6,924 6,947 6,929 6,872 6,868 6,862 6,815 128,366 127,885 126,790 127,088 126,852 126,090 126,040 125,955 125,339 23,366 22,885 21,790 22,088 21,852 21,090 21,040 125,955 125,339 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 52 Period 2036 - 2044 COST-BENEFIT ANALYSIS FOR AMAILA FALLS PROJECT MAIN ASSUMPTIONS Crude Oil Price (WTI) Demand Forecast GDP growth Total Sales GPL system T & D losses Year USD / bbl 2036 75 2037 75 2038 75 2039 75 2040 75 2041 75 2042 75 2043 75 2044 75 Year % 2036 3.1% 2037 3.1% 2038 3.1% 2039 3.1% 2040 3.1% 2041 3.1% 2042 3.1% 2043 3.1% 2044 3.1% GWh annual growth 1,555 5.1% 1,635 5.1% 1,719 5.1% 1,808 5.1% 1,901 5.1% 1,999 5.1% 2,102 5.1% 2,210 5.1% 2,324 5.1% in % Technical 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% GWh annual growth 2,178 5.1% 2,290 5.1% 2,407 5.1% 2,530 5.1% 2,659 5.1% 2,795 5.1% 2,938 5.1% 3,088 5.1% 3,246 5.1% Linden Power Company GWh 147 2.9% 151 2.9% 155 2.9% 160 2.9% 164 2.9% 169 2.9% 174 2.9% 179 2.9% 184 2.9% Self generation switching to the grid GWh 246 3.1% 254 3.1% 262 3.1% 270 3.1% 278 3.1% 287 3.1% 296 3.1% 305 3.1% 314 3.1% Total expected demand Expected demand growth GWh % 2,571 4.8% 2,694 4.8% 2,824 4.8% 2,959 4.8% 3,102 4.8% 3,251 4.8% 3,408 4.8% 3,572 4.8% 3,745 4.8% Non-technical Gross generation GPL system Average load Peak demand MW MW 294 425 308 446 322 467 338 490 354 513 371 538 389 564 408 591 427 620 - - - - - - - - - AMAILA FALLS COSTS PPA (fixed annual payment) k USD ECONOMIC BENEFITS Savings in Operating Costs Fuel Consumption Prices HFO (includes freight) LFO (includes freight) Generation mix Year 2036 2037 2038 2039 2040 2041 2042 2043 2044 USD / bbl USD / bbl 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 94% 6% 95% 5% 95% 5% 95% 5% 95% 5% 95% 5% 95% 5% 95% 5% 95% 5% bbl k USD bbl k USD 3,399,778 3,567,730 3,736,428 3,905,874 4,095,362 4,286,636 4,492,588 4,706,920 4,934,195 206,508 214,951 225,115 235,323 246,740 258,264 270,672 283,585 297,278 2,024,246 2,189,349 2,362,988 2,545,165 2,736,305 2,936,857 3,147,290 3,368,098 3,599,801 122,956 131,905 142,367 153,343 164,859 176,941 189,620 202,923 216,883 k USD 83,552 83,045 82,748 81,981 81,881 81,322 81,052 80,662 80,395 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 HFO LFO Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 Savings in Fuel Costs O&M Expenses O&M unit costs thermal engines O&M Amaila Falls USD / MWh USD / MWh Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 k USD k USD 22,414 19,874 23,520 20,980 24,684 22,144 25,905 23,365 27,186 24,646 28,530 25,990 29,941 27,401 31,420 28,880 32,973 30,433 PPA Guysuco Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 k USD k USD 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 Savings in O&M Expenses k USD Total Savings in Operating Costs Savings in Capital Expenditures in Thermal Plants Year Investment Cost USD / kW % Return on capital (assumes private inv Repayment period years Module MW New thermal capacity additions per year Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 MW-year MW-year Savings in CAPEX annual payments Year Fuel option - Emission Factor Carbon bonds price kg CO2 / kg diesel USD / t Reduction in Fuel Consumption Reduction in CO2 tonnes tonnes GHG Emissions Reduction k USD TOTAL ECONOMIC BENEFITS NET CASH FLOW 2,540 2,540 2,540 2,540 2,540 2,540 2,540 2,540 85,585 85,288 84,521 84,421 83,862 83,592 83,202 82,935 2036 2037 2038 2039 2040 2041 2042 2043 2044 28 28 21 21 28 28 35 35 28 28 35 35 35 35 35 35 35 35 97,435 65,489 102,227 70,281 108,616 76,670 119,797 87,851 126,186 94,240 134,173 102,227 142,159 110,213 150,145 118,200 158,132 126,186 31,946 31,946 31,946 31,946 31,946 31,946 31,946 31,946 31,946 1,100 16% 10 7 k USD k USD GHG Emissions Reduction 2,540 86,092 2036 2037 2038 2039 2040 2041 2042 2043 2044 3.07 10.43 211,620 649,675 k USD 212,059 651,020 211,298 648,686 209,340 642,673 209,086 641,893 207,658 637,511 206,969 635,395 205,973 632,336 205,291 630,244 6,776 6,790 6,766 6,703 6,695 6,649 6,627 6,595 6,573 124,814 124,321 123,999 123,170 123,062 122,457 122,165 121,743 121,455 124,814 124,321 123,999 123,170 123,062 122,457 122,165 121,743 121,455 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 53 Period 2045 – 2053 COST-BENEFIT ANALYSIS FOR AMAILA FALLS PROJECT MAIN ASSUMPTIONS Crude Oil Price (WTI) Demand Forecast GDP growth Total Sales GPL system T & D losses Year USD / bbl 2045 75 2046 75 2047 75 2048 75 2049 75 2050 75 2051 75 2052 75 2053 75 Year % 2045 3.1% 2046 3.1% 2047 3.1% 2048 3.1% 2049 3.1% 2050 3.1% 2051 3.1% 2052 3.1% 2053 3.1% GWh annual growth 2,443 5.1% 2,569 5.1% 2,701 5.1% 2,840 5.1% 2,986 5.1% 3,140 5.1% 3,302 5.1% 3,472 5.1% 3,650 5.1% in % Technical 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% GWh annual growth 3,412 5.1% 3,587 5.1% 3,770 5.1% 3,963 5.1% 4,166 5.1% 4,379 5.1% 4,603 5.1% 4,838 5.1% 5,086 5.1% Linden Power Company GWh 190 2.9% 195 2.9% 201 2.9% 207 2.9% 213 2.9% 219 2.9% 225 2.9% 232 2.9% 238 2.9% Self generation switching to the grid GWh 324 3.1% 334 3.1% 344 3.1% 355 3.1% 366 3.1% 377 3.1% 389 3.1% 401 3.1% 413 3.1% Total expected demand Expected demand growth GWh % 3,926 4.8% 4,116 4.8% 4,315 4.8% 4,524 4.8% 4,744 4.9% 4,975 4.9% 5,217 4.9% 5,470 4.9% 5,737 4.9% Non-technical Gross generation GPL system Average load Peak demand MW MW 448 649 470 681 493 714 516 749 542 785 568 823 595 863 624 905 655 949 - - - - - - - - - AMAILA FALLS COSTS PPA (fixed annual payment) k USD ECONOMIC BENEFITS Savings in Operating Costs Fuel Consumption Prices HFO (includes freight) LFO (includes freight) Generation mix Year 2045 2046 2047 2048 2049 2050 2051 2052 2053 USD / bbl USD / bbl 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 61.9 97.4 95% 5% 95% 5% 95% 5% 95% 5% 95% 5% 95% 5% 95% 5% 95% 5% 95% 5% bbl k USD bbl k USD 5,165,464 5,418,128 5,685,898 5,966,914 6,261,839 6,571,373 6,896,246 7,237,230 7,595,132 311,212 326,435 342,567 359,498 377,267 395,916 415,489 436,033 457,596 3,842,944 4,098,100 4,365,869 4,646,885 4,941,811 5,251,344 5,576,218 5,917,201 6,275,104 231,532 246,905 263,037 279,968 297,737 316,386 335,959 356,503 378,066 k USD 79,680 79,530 79,530 79,530 79,530 79,530 79,530 79,530 79,530 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 9.0 6.4 HFO LFO Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 Savings in Fuel Costs O&M Expenses O&M unit costs thermal engines O&M Amaila Falls USD / MWh USD / MWh Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 k USD k USD 34,603 32,063 36,313 33,773 38,108 35,568 39,991 37,451 41,968 39,428 44,042 41,502 46,220 43,680 48,505 45,965 50,904 48,364 PPA Guysuco Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 k USD k USD 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 9,007 Savings in O&M Expenses k USD Total Savings in Operating Costs Savings in Capital Expenditures in Thermal Plants Year Investment Cost USD / kW % Return on capital (assumes private inv Repayment period years Module MW New thermal capacity additions per year Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 Expansion Plan without Amaila Expansion Plan with Amaila Y 2014 MW-year MW-year Savings in CAPEX annual payments Year Fuel option - Emission Factor Carbon bonds price kg CO2 / kg diesel USD / t Reduction in Fuel Consumption Reduction in CO2 tonnes tonnes GHG Emissions Reduction k USD TOTAL ECONOMIC BENEFITS NET CASH FLOW 2,540 2,540 2,540 2,540 2,540 2,540 2,540 2,540 82,070 82,070 82,070 82,070 82,070 82,070 82,070 82,070 2045 2046 2047 2048 2049 2050 2051 2052 2053 42 42 42 42 42 42 42 42 49 49 49 49 56 56 56 56 56 56 169,313 137,367 178,897 146,951 188,480 156,535 198,064 166,118 210,843 178,897 222,024 190,078 236,399 204,453 249,178 217,232 261,956 230,010 31,946 31,946 31,946 31,946 31,946 31,946 31,946 31,946 31,946 1,100 16% 10 7 k USD k USD GHG Emissions Reduction 2,540 82,220 2045 2046 2047 2048 2049 2050 2051 2052 2053 3.07 10.43 203,465 624,636 k USD 203,081 623,460 203,081 623,460 203,081 623,460 203,081 623,460 203,081 623,460 203,081 623,460 203,081 623,460 203,081 623,460 6,515 6,503 6,503 6,503 6,503 6,503 6,503 6,503 6,503 120,681 120,518 120,518 120,518 120,518 120,518 120,518 120,518 120,518 120,681 120,518 120,518 120,518 120,518 120,518 120,518 120,518 120,518 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 54 4.5. OPPORTUNITY COST FOR GPL (MAXIMUM ANNUAL FIXED PAYMENT) ME also estimated the maximum fixed annual payment (GPL’s opportunity cost) for Amaila’s output which verifies that the present value of GPL’s total generation expenses (CAPEX and OPEX) is equal in both capacity expansion options analyzed. The said annual fixed payment is – 122,724 k USD, considering Base Case assumptions. Even though this ceiling fixed annual payment assures Amaila’s structural competitiveness compared to GPL’s thermal expansion option (opportunity cost), it also creates a financial constraint on GPL in the short to medium term: supply costs including Amaila are higher than supply costs deselecting Amaila as a candidate project. In turn, high average supply costs relative to other supply choices, discourage market expansion and increases demand risk for GPL. Therefore, ME re-estimated the maximum payment assuming a relative more conservative scenario: no self generators decide to purchase power from GPL (because there would be no room for tariff incentives) and a higher discount rate (14%) than Base Case because GPL’s demand risk increases: such conditions make the annual fixed payment to drop down to – 106,785 k USD. The table below summarizes key assumptions for each estimated maximum fixed annual payment: Crude Oil (USD / bbl) Base Case 75 75 Discount Rate 12% 14% Demand GPL's maximum annual payment for Amaila's output same as Base Case without self generators Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project -122,724 -106,785 # of initial years when costs exceeds benefits 20 7 55 SECTION IV: COMPETITIVENESS OF AMAILA FALLS SUPPLY COST In this Section, ME compares GPL’s supply cost and cost of self generation to discuss the competitiveness of the project in the short run. In the medium to long term, assuming crude oil prices of 75 USD / bbl, GPL’s average supply costs including Amaila Falls in its expansion plan are lower than the alternative expansion option (diesel-fired generators). 5. GPL SUPPLY COST Amaila Falls hydro power plant project will sell its energy output primarily to GPL, at a fixed annual payment of -105,000 k USD, regardless actual demand. In other words, the power purchase agreement is a take-or-pay contract. Amaila Falls project will be competitive if other supply options available for GPL (or any other off-taker) have higher prices than Amaila’s supply cost (PPA). GPL’s alternative (to Amaila Falls) supply cost is the long run marginal cost (LRMC) of the most competitive thermal technology available to expand its power system (bunkerfired engines). Such LRMC is in between 13.0 and 14.0 ¢USD / kWh, assuming a crude oil price (WTI) of 75 USD / bbl and expected dispatch around 70 %. As shown with the economic indicators of the cost-benefit analysis, the inclusion of Amaila Falls in GPL’s generation expansion plan lowers the net present value of GPL’s generation expenses. The inclusion of Amaila Falls cuts down GPL’s average supply costs to 11.5 ¢USD / kWh in the medium to long term. However, in the early years of the project (first year of Amaila’s operation in the Base Case) and given that contractual arrangement is take-or-pay, GPL’s total generating expenses including the power purchase agreement with Amaila Falls are closer or even 5 - 10 % higher than GPL’s generation expenses without including Amaila Falls (and only adding needed thermal generators to meet demand growth): Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 56 GPL's generating expenses per unit of demand With and without Amaila Falls in the expansion plan 16.0 15.5 15.0 14.5 14.0 100 % Thermal Expansion in cUSD / kWh 13.5 13.0 12.5 12.0 11.5 Expansion with Amaila as of Y 2014 (includes carbon credits) 11.0 10.5 10.0 Y 2014: Amaila Falls begins commercial operations 9.5 20 36 20 37 20 34 20 35 20 32 20 33 20 30 20 31 20 28 20 29 20 26 20 27 20 24 20 25 20 23 20 21 20 22 20 19 20 20 20 17 20 18 20 15 20 16 20 13 20 14 20 11 20 12 20 09 20 10 9.0 This short run effect can be mitigated with a more aggressive market expansion because the fixed annual payment is distributed among a larger demand. In any case, GPL’s degree of success in attracting industrial self generators back to the grid, will mostly depend on the tariff12 at which GPL can deliver the energy to such customers compared to their self-generation cost. 6. COST OF SELF GENERATION Based on data collected in the self generators survey and own assumptions regarding typical heat content and machine efficiency, ME estimated the development cost of self-generation as the sum of its variable costs of production and its investment cost. The following table summarizes the set of assumptions adopted to estimate the cost of self generation: Investment Cost 600 USD / kW Repayment period 10 years O&M 4.0 USD / MWh Type of fuel Light fuel oil Fuel cost on site 97.4 USD / bbl Gross capacity 200 – 1000 kVA Heat rate 33 - 36 % Expected dispatch 70 % 12 Reliability of service will also play a key role in market expansion Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 57 The estimated self generation costs are: • between 19.3 and 20.7 ¢USD / kWh, for an industry assessing the costs of installing a new power generator. • between 15.8 and 17.2 ¢USD / kWh for existing self generators (does not include investment cost – sunk cost -, only operating costs). The above estimated self generation costs represent the break-even price for an industrial customer, assuming same reliability in supply options (GPL vs self generation). The cost of self generation (both for prospective and existing self generators as well) is higher than GPL’s average supply costs. It’s worth noting that these figures are not directly comparable with GPL’s supply cost (transmission and distribution charges have to be added). GPL's generating expenses and Costs of self generation 21.0 20.5 20.0 19.5 Prospective self generator Total costs (includes capital expenditures) 19.0 18.5 18.0 17.5 in cUSD / kWh 17.0 16.5 Existing self generators Variable costs 16.0 15.5 15.0 14.5 14.0 13.5 100 % Thermal Expansion 13.0 12.5 12.0 11.5 11.0 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 20 36 20 37 20 34 20 35 20 32 20 33 20 30 20 31 20 28 20 29 20 26 20 27 20 24 20 25 20 23 20 21 20 22 20 19 20 20 20 17 20 18 20 16 20 14 20 15 20 13 20 09 20 10 10.0 Expansion with Amaila as of Y 2014 Note: GPL's generating expenses (T&D charges are not included) 20 11 20 12 10.5 58 SECTION V: SENSITIVITY ANALYSIS Based on the cost benefit analysis developed for the Base Case, ME identified the main factors that negatively influence the economic rationale of the project: • Fuel prices • Demand growth / market expansion in the short run 7. SENSITIVITY TO CRUDE OIL PRICE Variable operating costs for thermal plants mostly depend on fuel costs. Direct savings in fuel costs account for approximately 70 % of total economic benefits of Amaila Falls project. In turn, fuel prices are positively correlated to crude oil prices. Future scenarios of high crude oil prices will be an upside for Amaila Falls project. Conversely, scenarios of low crude oil prices are a downside. The following table shows the project’s net present value and economic rate of return (ERR) for different scenarios of future crude oil prices (with and without including carbon credits as economic benefit): Sensitivity to WTI (net cash flow includes carbon credits).- Crude Oil price NPV (@ 12%) Base Case (*) Downside Cases USD / bbl 75 70 65 60 55 k USD 186,886 145,052 103,217 61,383 19,549 ERR BCR (**) in % 83% 37% 23% 17% 13% 0.70 0.67 0.64 0.61 0.58 # of initial years with negative cash flow (cost > benefits) 1 2 4 6 8 (*) consistent with World Bank's latest projections (**) Benefit - Cost ratio = NPV (Benefits) / NPV (Costs) Time horizon: 40 years Sensitivity to WTI (net cash flow does not include carbon credits).- Crude Oil price NPV (@ 12%) Base Case (*) Downside Cases USD / bbl 75 70 65 60 55 k USD 132,390 90,556 48,721 6,887 -34,947 ERR in % 32% 21% 16% 12% 10% BCR (**) 0.66 0.63 0.60 0.57 0.54 # of initial years with negative cash flow (cost > benefits) 3 5 7 8 20 The number of initial years with negative cash flow (i.e. costs greater than benefits) increase as WTI decreases, because direct savings in fuel costs are reduced. In other words, scenarios of relative low crude oil prices reduce the competitiveness of hydro projects vis a vis thermal expansion. Assuming no economic benefits from carbon emission reduction and expected crude oil prices lower than 60 USD / bbl, drastically reduce direct savings in fuel costs with Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 59 respect to Base Case; and project’s net cash flow turns negative until termination of PPA (20 years). 8. SENSITIVITY TO MARKET EXPANSION In the short run, annual fixed payment for Amaila’s output may outweigh the direct savings in operating costs and capital expenditures in new thermal generators. Instead, in the medium to long run benefits offset the costs. Market expansion contributes to compensate the temporary imbalance between total costs and total benefits. The following table shows the project’s economic indicators for different scenarios of market expansion: Sensitivity to market expansion Scenario Base Case (*) Upside Case Self generators switching to the grid GWh-year 131 GWh (60 % in 2014 & 40 % in 2015) NPV (@ 12%) Economic rate of return (ERR) Benefit / Cost ratio k USD in % BCR # of initial years with negative cash flow (costs larger than benefits) 186,252 94% 0.70 192,463 positive cash flow all years 0.71 105 GWh as of Y 2014 171,656 55% 0.69 2 79 GWh as of Y 2014 156,160 37% 0.68 3 109,313 21% 0.65 7 131 GWh as of Y 2014 1 zero Downside Cases: 20% less than BC 40 % less than BC Self generators decide not to switch to the grid 8.1. UPSIDE CASE If it is assumed that 100 % of the estimated demand from self generation (131 GWhyear) is connected to the grid during the first year (2014) of Amaila Falls operation, benefits are greater than costs (compared to – 5,800 thousand USD in Base Case): Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 60 GPL's generating expenses per unit of demand With and without Amaila Falls in the expansion plan 16.0 15.5 15.0 14.5 14.0 100 % Thermal Expansion in cUSD / kWh 13.5 13.0 12.5 12.0 11.5 Expansion with Amaila as of Y 2014 (includes carbon credits) 11.0 10.5 10.0 Y 2014: Amaila Falls begins commercial operations 9.5 8.2. 20 36 20 37 20 34 20 35 20 32 20 33 20 30 20 31 20 28 20 29 20 26 20 27 20 24 20 25 20 23 20 21 20 22 20 19 20 20 20 17 20 18 20 15 20 16 20 13 20 14 20 11 20 12 20 09 20 10 9.0 DOWNSIDE CASE On the contrary, assuming there are no firms interested in being supplied by GPL instead of self generating (and despite the cost differential), Amaila’s cash flow turns negative for seven years, as seen in the graph below: GPL's generating expenses per unit of demand With and without Amaila Falls in the expansion plan 16.0 15.5 15.0 14.5 14.0 100 % Thermal Expansion in cUSD / kWh 13.5 13.0 12.5 12.0 11.5 Expansion with Amaila as of Y 2014 (includes carbon credits) 11.0 10.5 10.0 Y 2014: Amaila Falls begins commercial operations 9.5 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 20 36 20 37 20 34 20 35 20 32 20 33 20 30 20 31 20 28 20 29 20 26 20 27 20 24 20 25 20 23 20 21 20 22 20 19 20 20 20 17 20 18 20 15 20 16 20 13 20 14 20 11 20 12 20 09 20 10 9.0 61 SECTION VI: REVIEW OF EXISTING HYDROLOGY STUDIES Existing studies on the hydrology and project design were reviewed in order to verify the conclusions outlined by MWH and to assess possible design enhancements based on available field data. The review of hydrology studies included the following documents submitted by the Client: • Amaila Falls Hydroelectric Project – Guyana - Feasibility Study Report – Hydrology - Prepared by MWH – December 2001 • Amaila Falls Hydro - Estimated Monthly Energy and Average Power for a Range of Load Factors – Prepared by MWH – August 2009 • GEOTECHNICAL BASELINE REPORT FOR BIDDING Hydroelectric Power Project – Generating Facilities - June 2008 Amaila Falls • Amaila Falls Hydroelctric Project – Generating Facilities – Section 8 – Owners Requirement Drawings – June 2008 • PPA multiscenarioCovermemo_20090820.pdf See Annex II for a complete description of the hydrology and design aspects reviewed. Main conclusions are summarized below: The design of Amaila Falls Project encountered several problems arising from the lack of hydrologic data. Therefore, the best techniques available were applied to cope with the lack of information but even so, several questions remained unanswered, such as the following: • The flows used were obtained by extrapolating the results from Kaieter Falls Station with different transfer coefficients and then adopting 0.30 without further justification. This may cause some uncertainty regarding the expected power generation. • The maximum flow adopted to design the dam was the result of transforming the Probable Maximum Precipitation value into the Probable Maximum Flow by adopting a C coefficient (Creaguer’s formula) that has no direct justification, thus causing uncertainty as regards the maximum flow adopted for the design at 5.010 m3/s. • In addition, the Probable Maximum Flood was assessed in the current basin status, with no deforestation or mining exploitation. Any modification of the basin in such respect will have an impact on the increase in the maximum value considered. • The flows assumed for different return periods, which set the maximum values to be adopted during the construction period, also include coefficients and parameters adopted without any actual data on the site. • In order to obtain more accurate information, it would be desirable to install a hydro-meteorological station in a section of the river that is representative of the Project. Even if the works start soon, the information obtained will always be useful and will allow future adjustment of the parameters necessary for operation. With respect to the studies conducted on the behavior of generation with different dam heights and installed capacities, it was concluded that: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 62 • Energy production is marked by hydraulicity in the different months of the year. In wet months (June to September), more power can be generated and demand is covered. • In months with low hydraulicity, demand is only partially covered. • The above shows the reservoir’s poor regulation, considering that in wet months or periods the surplus flows will be spilled. • As the reservoir level is increased (more regulation) or installed capacity is reduced, the percentage of demand coverage grows for the same load factor. • In the actual case, 140 MW at delivery point and maximum reservoir level at 462.00 m.a.s.l., the trend is confirmed: even with smaller load factors, there is a deficit in power generation in months with low hydraulicity. The potential increase in dam height will have little influence on the installed capacity due to the great existing fall, although it will improve annual power generation, considering the greater regulation capacity and the following features: • The increase in the maximum level from 462 to 468 m represents an increase of 26 % in the maximum height of Amaila Dam and 30 % in Kuribrong Dam, with major economic implications. • In addition to more investment, other aspects linked to the larger flooded area should be considered, in particular, associated environmental aspects. • Another alternative to enhance the dam’s regulation capacity, and therefore its annual average energy, could be the implementation of circular sector gates allowing some of the flows in wet months to be stored, thus reducing spilling. • It is considered, however, that this additional regulation capacity would be limited and equal to approximately only 10% of the annual spilling. • The convenience of installing gates to reduce the expected investment remains to be considered. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 63 SECTION VII: MAIN CONCLUSIONS Amaila Falls project brings structural benefits to the power system: a generation mix hydro-thermal is better to hedge risks (oil prices volatility) than a system that entirely relies on thermal plants. Cost – benefit analysis It evidences that the project is economically profitable. The inclusion of Amaila Falls in GPL’s expansion plan reduces GPL’s net present value of generation expenses throughout the study time horizon. In other words, total benefits outweigh total costs of the project. It’s worth noting that Amaila Falls benefits are mainly concentrated in the medium to long term, while PPA is evenly distributed during 20 years. Assuming a WTI of 75 USD / bbl, an annual demand growth of 5 % in the steady state (consistent with a GDP growth of 3.0 %) and the addition to the grid of 131 GWh currently self generating (60 % in 2014 and 40 % in 2015), the project’s economic indicators are the following: NPV (kUSD) (@ 12%) ERR Benefit - Cost Ratio BCR 186,886 83% 0.70 Due to plant’s size (larger than 20 MW), Amaila Falls may not be eligible for carbon credits. If carbon credits are not considered in the project’s benefits, the above economic indicators are the following: NPV (kUSD) (@ 12%) ERR Benefit - Cost Ratio BCR 132,390 32% 0.66 GPL’s alternative supply cost is the long run marginal cost (LRMC) of the most competitive thermal technology available to expand its power system (bunker-fired engines). Such LRMC is in between 13.0 and 14.0 ¢USD / kWh, assuming a crude oil price (WTI) of 75 USD / bbl. Competitiveness The consideration of Amaila Falls in the capacity expansion plan at a fixed annual payment of 105,000 k USD lowers the NPV of GPL’s generation expenses throughout the study time horizon, as demonstrated in the cost-benefit analysis. The inclusion of Amaila Falls cuts down GPL’s average supply costs to 11.5 ¢USD / kWh in the medium to long term. In the short run, GPL’s average supply costs are higher than in the long term, in the order of 12.6 ¢USD / kWh (effect of a take-or-pay contractual arrangement and demand lower or close to energy delivered). Market expansion by attracting industrial self generators back to the grid mitigates this short run effect because the fixed annual payment is absorbed by a larger demand. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 64 Costs of self-generation (assuming a crude oil price of 75 USD / bbl) are estimated between 15.8 and 20.7 ¢USD / kWh. These figures represent represent the break-even price for an industrial customer, assuming same reliability in supply options (GPL vs self generation). Costs of self generation are higher than GPL’s average supply costs. It’s worth noting that these figures are not directly comparable with GPL’s supply cost (transmission and distribution charges have to be added). Sensitivity to WTI Future scenarios of high crude oil prices contribute to increase the competitiveness of Amaila Falls vis a vis the thermal expansion (upside). Conversely, scenarios of low crude oil prices are a downside for the project. The following tables show the economic indicators of the cost-benefit analysis for different scenarios of future crude oil prices, with and without considering carbon credits as part of the total benefits: Sensitivity to WTI (net cash flow includes carbon credits).- Crude Oil price NPV (@ 12%) Base Case (*) Downside Cases USD / bbl 75 70 65 60 55 k USD 186,886 145,052 103,217 61,383 19,549 ERR BCR (**) in % 83% 37% 23% 17% 13% 0.70 0.67 0.64 0.61 0.58 # of initial years with negative cash flow (cost > benefits) 1 2 4 6 8 (*) consistent with World Bank's latest projections (**) Benefit - Cost ratio = NPV (Benefits) / NPV (Costs) Time horizon: 40 years Sensitivity to WTI (net cash flow does not include carbon credits).- Crude Oil price NPV (@ 12%) Base Case (*) Downside Cases USD / bbl 75 70 65 60 55 k USD 132,390 90,556 48,721 6,887 -34,947 ERR in % 32% 21% 16% 12% 10% BCR (**) 0.66 0.63 0.60 0.57 0.54 # of initial years with negative cash flow (cost > benefits) 3 5 7 8 20 The number of initial years with negative cash flow (i.e. costs greater than benefits) increase as WTI decreases, because direct savings in fuel costs are reduced. If one assumes no economic benefits from carbon emission reduction and expected crude oil prices lower than 60 USD / bbl, it drastically reduce direct savings in fuel costs with respect to Base Case; and project’s net cash flow turns negative until termination of PPA (20 years). Sensitivity to market expansion In the short run, annual fixed payment for Amaila’s output may outweigh the direct savings in operating costs and capital expenditures in new thermal generators. Instead, in the medium to long run benefits offset the costs. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 65 Market expansion contributes to compensate the temporary imbalance between total costs and total benefits. The following table shows the project’s economic indicators for different scenarios of market expansion: Sensitivity to market expansion Scenario Base Case (*) Upside Case Self generators switching to the grid GWh-year 131 GWh (60 % in 2014 & 40 % in 2015) NPV (@ 12%) Economic rate of return (ERR) Benefit / Cost ratio k USD in % BCR # of initial years with negative cash flow (costs larger than benefits) 186,886 83% 0.70 195,664 positive cash flow all years 0.71 105 GWh as of Y 2014 170,318 49% 0.69 2 79 GWh as of Y 2014 153,363 34% 0.68 3 100,870 19% 0.64 7 131 GWh as of Y 2014 1 zero Downside Cases: 20% less than BC 40 % less than BC Self generators decide not to switch to the grid The number of initial years with negative cash flow (i.e. costs greater than benefits) increases as market expansion decreases. High supply costs in the short run might also be mitigated considering efficient contractual arrangements (fuel cost deduction during dry seasons, increasing annuity over time, etc.). Upside: If it is assumed that 100 % of the estimated demand from self generation (131 GWh-year) is connected to the grid during the first year (2014) of Amaila Falls operation, benefits are greater than costs in the first year since the first year of Amaila’s operation (compared to – 5,500 thousand USD in Base Case). Downside: on the contrary, assuming there are no firms interested in being supplied by GPL instead of self generating (and despite the cost differential), costs offset benefits during seven years. Review on hydrology studies The hydrology study done by MWH encountered some difficulties due to lack of direct hydrological data at the project site. Given the above mentioned constraint, MWH applied best practices to process the available information. Reservoir operation: Seasonal regulation and production of firm energy during drier months is limited. The optimization of the project design is limited because all available data has been already considered. Design improvements would require additional hydrological data collection. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 66 ANNEX I – SIMULATION MODEL OUTPUTS Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 67 Simulation Model output: Generation balance without including Amaila Falls among selected candidates Period 2009 - 2022 SIMULATION MODEL OUTPUT (GENERATION BALANCE) - Option without including Amaila Falls among selected candidates ASSUMPTIONS - Base Case Demand Forecast Total Sales GPL system T & D losses Year 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 GWh annual growth 393 418 6.3% 431 3.2% 453 5.0% 476 5.1% 500 5.1% 525 5.1% 552 5.1% 581 5.2% 611 5.2% 643 5.2% 677 5.2% 712 5.3% 750 5.3% in % Technical 11.4% 10.6% 9.9% 9.3% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% Non-technical 21.6% 19.4% 17.5% 15.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% Gross generation GPL system GWh 587 597 619 647 673 701 737 775 815 857 902 949 999 1,052 Linden Power Company GWh 66 68 70 72 74 76 79 81 83 86 88 91 94 97 Self generation switching to the grid GWh 79 131 135 139 143 148 152 157 161 Total expected demand Expected demand growth GWh % 653 665 1.8% 689 3.6% 719 4.3% 748 4.0% MW MW 75 108 76 110 79 114 82 119 85 124 Average load Peak demand - - - - - 856 14.5% 98 142 947 10.6% 991 4.7% 1,037 4.7% 1,086 4.7% 1,138 4.7% 1,192 4.8% 1,249 4.8% 1,310 4.8% 108 157 113 164 118 172 124 180 130 188 136 197 143 207 149 217 GENERATION BALANCE - WITHOUT INCLUDING AMAILA AMONG SELECTED PROJECT CANDIDATES TO EXPAND THE SYSTEM DISPATCH OF POWER PLANTS: Exisiting Thermal Power Plants Guysuco Cogenerator (PPA) New Thermal Facilities Total Generation GWh GWh GWh GWh 614 39 653 584 81 665 608 81 689 601 81 37 719 629 81 37 748 515 81 261 856 494 81 372 947 500 81 409 991 472 81 484 1,037 484 81 521 1,086 461 81 596 1,138 478 81 633 1,192 461 81 707 1,249 447 81 782 1,310 MW MW MW 143 143 147 147 139 139 135 7 142 132 132 132 42 174 174 21 195 195 7 202 202 14 216 216 7 223 223 14 237 237 7 244 244 14 258 258 14 272 % 32% 34% 22% 19% 23% 25% 23% 26% 24% 26% 24% 25% 26% GENERATION CAPACITY: Existing thermal Annual Thermal new additions Total Installed Capacity Reserve margin (Installed Capacity / Peak demand) Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 7% 68 Simulation Model output: Generation balance without including Amaila Falls among selected candidates Period 2023 - 2036 SIMULATION MODEL OUTPUT (GENERATION BALANCE) - Option without including Amaila Falls among selected candidates ASSUMPTIONS - Base Case Demand Forecast Total Sales GPL system T & D losses Year 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 GWh annual growth 790 5.3% 832 5.3% 876 5.3% 923 5.4% 973 5.4% 1,025 5.4% 1,081 5.4% 1,140 5.5% 1,202 5.5% 1,268 5.5% 1,338 5.5% 1,407 5.1% 1,479 5.1% 1,555 5.1% in % Technical Non-technical 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% Gross generation GPL system GWh 1,107 1,166 1,229 1,295 1,364 1,438 1,516 1,599 1,686 1,779 1,876 1,972 2,073 2,178 Linden Power Company GWh 100 103 106 109 112 116 119 123 127 131 135 139 143 147 Self generation switching to the grid GWh Total expected demand Expected demand growth GWh % Average load Peak demand MW MW 166 1,373 4.9% 157 227 171 1,440 4.9% 164 238 176 1,511 4.9% 182 1,585 4.9% 172 250 181 262 187 1,664 5.0% 193 1,747 5.0% 190 275 199 1,835 5.0% 205 1,927 5.0% 211 2,024 5.1% 218 2,127 5.1% 225 2,236 5.1% 232 2,342 4.8% 239 2,454 4.8% 246 2,571 4.8% 199 289 209 304 220 319 231 335 243 352 255 370 267 388 280 406 294 425 GENERATION BALANCE - WITHOUT INCLUDING AMAILA AMONG SELECTED PROJECT CANDIDATES TO EXPAND THE SYSTEM DISPATCH OF POWER PLANTS: Exisiting Thermal Power Plants Guysuco Cogenerator (PPA) New Thermal Facilities Total Generation GWh GWh GWh GWh 436 81 856 1,373 429 81 931 1,440 425 81 1,005 1,511 388 81 1,117 1,585 392 81 1,191 1,664 363 81 1,303 1,747 339 81 1,414 1,835 357 81 1,489 1,927 343 81 1,601 2,024 297 81 1,749 2,127 294 81 1,861 2,236 289 81 1,973 2,342 252 81 2,122 2,454 220 81 2,270 2,571 MW MW MW 272 14 286 286 14 300 300 14 314 314 21 335 335 14 349 349 21 370 370 21 391 391 14 405 405 21 426 426 28 454 454 21 475 475 21 496 496 28 524 524 28 552 % 26% 26% 26% 28% 27% 28% 29% 27% 27% 29% 28% 28% 29% 30% GENERATION CAPACITY: Existing thermal Annual Thermal new additions Total Installed Capacity Reserve margin (Installed Capacity / Peak demand) Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 69 Simulation Model output: Generation balance without including Amaila Falls among selected candidates Period 2037 - 2050 SIMULATION MODEL OUTPUT (GENERATION BALANCE) - Option without including Amaila Falls among selected candidates ASSUMPTIONS - Base Case Demand Forecast Total Sales GPL system T & D losses Year 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 GWh annual growth 1,635 5.1% 1,719 5.1% 1,808 5.1% 1,901 5.1% 1,999 5.1% 2,102 5.1% 2,210 5.1% 2,324 5.1% 2,443 5.1% 2,569 5.1% 2,701 5.1% 2,840 5.1% 2,986 5.1% 3,140 5.1% in % Technical Non-technical 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% Gross generation GPL system GWh 2,290 2,407 2,530 2,659 2,795 2,938 3,088 3,246 3,412 3,587 3,770 3,963 4,166 4,379 Linden Power Company GWh 151 155 160 164 169 174 179 184 190 195 201 207 213 219 Self generation switching to the grid GWh Total expected demand Expected demand growth GWh % Average load Peak demand MW MW 254 2,694 4.8% 308 446 262 2,824 4.8% 322 467 270 2,959 4.8% 278 3,102 4.8% 338 490 354 513 287 3,251 4.8% 371 538 296 3,408 4.8% 389 564 305 3,572 4.8% 314 3,745 4.8% 324 3,926 4.8% 334 4,116 4.8% 344 4,315 4.8% 355 4,524 4.8% 366 4,744 4.9% 377 4,975 4.9% 408 591 427 620 448 649 470 681 493 714 516 749 542 785 568 823 GENERATION BALANCE - WITHOUT INCLUDING AMAILA AMONG SELECTED PROJECT CANDIDATES TO EXPAND THE SYSTEM DISPATCH OF POWER PLANTS: Exisiting Thermal Power Plants Guysuco Cogenerator (PPA) New Thermal Facilities Total Generation GWh GWh GWh GWh 231 81 2,382 2,694 212 81 2,531 2,824 161 81 2,717 2,959 155 81 2,866 3,102 118 81 3,052 3,251 100 81 3,227 3,408 74 81 3,417 3,572 57 81 3,607 3,745 10 81 3,835 3,926 81 4,035 4,116 81 4,234 4,315 81 4,443 4,524 81 4,663 4,744 81 4,894 4,975 MW MW MW 552 21 573 573 28 601 601 35 636 636 28 664 664 35 699 699 35 734 734 35 769 769 35 804 804 42 846 846 42 888 888 42 930 930 42 972 972 49 1,021 1,021 49 1,070 % 29% 29% 30% 29% 30% 30% 30% 30% 30% 30% 30% 30% GENERATION CAPACITY: Existing thermal Annual Thermal new additions Total Installed Capacity Reserve margin (Installed Capacity / Peak demand) Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 30% 30% 70 Simulation Model output: Generation balance including Amaila Falls among selected candidates Period 2009 - 2022 SIMULATION MODEL OUTPUT (GENERATION BALANCE) - Option including Amaila Falls among selected candidates ASSUMPTIONS - Base Case Demand Forecast Total Sales GPL system T & D losses Year 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 GWh annual growth 393 418 6.3% 431 3.2% 453 5.0% 476 5.1% 500 5.1% 525 5.1% 552 5.1% 581 5.2% 611 5.2% 643 5.2% 677 5.2% 712 5.3% 750 5.3% in % Technical 11.4% 10.6% 9.9% 9.3% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% Non-technical 21.6% 19.4% 17.5% 15.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 949 999 1,052 Gross generation GPL system GWh 587 597 619 647 673 Linden Power Company GWh Self generation switching to the grid GWh Total expected demand Expected demand growth GWh % 653 665 1.8% 689 3.6% 719 4.3% 748 4.0% MW MW 75 108 76 110 79 114 82 119 85 124 Average load Peak demand 66 - 68 - 70 - 72 - 74 - 701 737 775 815 857 902 76 79 81 83 86 88 91 94 97 79 131 135 139 143 148 152 157 161 856 14.5% 947 10.6% 991 4.7% 1,037 4.7% 1,086 4.7% 1,138 4.7% 1,192 4.8% 1,249 4.8% 1,310 4.8% 98 142 108 157 113 164 118 172 124 180 130 188 136 197 143 207 149 217 GENERATION BALANCE - WITH AMAILA AMONG SELECTED PROJECT CANDIDATES TO EXPAND THE SYSTEM DISPATCH OF POWER PLANTS: Amaila Falls Exisiting Thermal Power Plants Guysuco Cogenerator (PPA) New Thermal Facilities Total Generation GENERATION CAPACITY: Amaila Falls Existing thermal Annual Thermal new additions Total Installed Capacity Reserve margin (Installed Capacity / Peak demand) GWh GWh GWh GWh GWh 614 39 653 584 81 665 608 81 689 601 81 37 719 629 81 37 748 813 43 856 862 81 4 947 872 81 38 991 892 81 64 1,037 912 81 93 1,086 921 81 135 1,138 930 81 181 1,192 949 81 219 1,249 983 81 246 1,310 MW MW MW 143 143 147 147 139 139 135 7 142 132 132 148 132 280 148 132 280 148 132 280 148 132 280 148 132 280 148 132 280 148 132 280 148 132 280 148 132 280 % 32% 34% 22% 19% 92% 74% 66% 59% 52% 45% 38% 32% 26% Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 7% 71 Simulation Model output: Generation balance including Amaila Falls among selected candidates Period 2023 - 2036 SIMULATION MODEL OUTPUT (GENERATION BALANCE) - Option including Amaila Falls among selected candidates ASSUMPTIONS - Base Case Demand Forecast Total Sales GPL system T & D losses Year 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 GWh annual growth 790 5.3% 832 5.3% 876 5.3% 923 5.4% 973 5.4% 1,025 5.4% 1,081 5.4% 1,140 5.5% 1,202 5.5% 1,268 5.5% 1,338 5.5% 1,407 5.1% 1,479 5.1% 1,555 5.1% in % Technical Non-technical 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% Gross generation GPL system GWh 1,107 1,166 1,229 1,295 1,364 1,438 1,516 1,599 1,686 1,779 1,876 1,972 2,073 2,178 Linden Power Company GWh 100 103 106 109 112 116 119 123 127 131 135 139 143 147 Self generation switching to the grid GWh Total expected demand Expected demand growth GWh % Average load Peak demand MW MW 166 1,373 4.9% 157 227 171 1,440 4.9% 164 238 176 1,511 4.9% 182 1,585 4.9% 172 250 181 262 187 1,664 5.0% 193 1,747 5.0% 199 1,835 5.0% 205 1,927 5.0% 211 2,024 5.1% 218 2,127 5.1% 225 2,236 5.1% 232 2,342 4.8% 239 2,454 4.8% 246 2,571 4.8% 190 275 199 289 209 304 220 319 231 335 243 352 255 370 267 388 280 406 294 425 GENERATION BALANCE - WITH AMAILA AMONG SELECTED PROJECT CANDIDATES TO EXPAND THE SYSTEM DISPATCH OF POWER PLANTS: Amaila Falls Exisiting Thermal Power Plants Guysuco Cogenerator (PPA) New Thermal Facilities Total Generation GENERATION CAPACITY: Amaila Falls Existing thermal Annual Thermal new additions Total Installed Capacity Reserve margin (Installed Capacity / Peak demand) GWh GWh GWh GWh GWh 983 81 309 1,373 983 81 376 1,440 983 81 447 1,511 983 81 521 1,585 983 81 600 1,664 983 81 683 1,747 983 81 771 1,835 983 81 863 1,927 983 81 960 2,024 983 81 1,063 2,127 983 81 1,172 2,236 983 81 1,278 2,342 983 81 1,390 2,454 983 81 1,507 2,571 MW MW MW 148 132 14 294 148 146 14 308 148 160 14 322 148 174 21 343 148 195 14 357 148 209 21 378 148 230 21 399 148 251 14 413 148 265 21 434 148 286 28 462 148 314 21 483 148 335 21 504 148 356 28 532 148 384 28 560 % 26% 26% 26% 28% 27% 28% 29% 27% 27% 29% 28% 28% 29% 30% Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 72 Simulation Model output: Generation balance including Amaila Falls among selected candidates Period 2037 – 2050 SIMULATION MODEL OUTPUT (GENERATION BALANCE) - Option including Amaila Falls among selected candidates ASSUMPTIONS - Base Case Demand Forecast Total Sales GPL system T & D losses Year 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 GWh annual growth 1,635 5.1% 1,719 5.1% 1,808 5.1% 1,901 5.1% 1,999 5.1% 2,102 5.1% 2,210 5.1% 2,324 5.1% 2,443 5.1% 2,569 5.1% 2,701 5.1% 2,840 5.1% 2,986 5.1% 3,140 5.1% in % Technical Non-technical 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 8.1% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% Gross generation GPL system GWh 2,290 2,407 2,530 2,659 2,795 2,938 3,088 3,246 3,412 3,587 3,770 3,963 4,166 4,379 Linden Power Company GWh 151 155 160 164 169 174 179 184 190 195 201 207 213 219 Self generation switching to the grid GWh Total expected demand Expected demand growth GWh % Average load Peak demand MW MW 254 2,694 4.8% 308 446 262 2,824 4.8% 322 467 270 2,959 4.8% 278 3,102 4.8% 338 490 354 513 287 3,251 4.8% 296 3,408 4.8% 305 3,572 4.8% 314 3,745 4.8% 324 3,926 4.8% 334 4,116 4.8% 344 4,315 4.8% 355 4,524 4.8% 366 4,744 4.9% 377 4,975 4.9% 371 538 389 564 408 591 427 620 448 649 470 681 493 714 516 749 542 785 568 823 GENERATION BALANCE - WITH AMAILA AMONG SELECTED PROJECT CANDIDATES TO EXPAND THE SYSTEM DISPATCH OF POWER PLANTS: Amaila Falls Exisiting Thermal Power Plants Guysuco Cogenerator (PPA) New Thermal Facilities Total Generation GENERATION CAPACITY: Amaila Falls Existing thermal Annual Thermal new additions Total Installed Capacity Reserve margin (Installed Capacity / Peak demand) GWh GWh GWh GWh GWh 983 81 1,630 2,694 983 81 1,760 2,824 983 81 1,895 2,959 983 81 2,038 3,102 983 81 2,187 3,251 983 81 2,344 3,408 983 81 2,508 3,572 983 81 2,681 3,745 983 81 2,862 3,926 983 81 3,052 4,116 983 81 3,251 4,315 983 81 3,460 4,524 983 81 3,680 4,744 983 81 3,911 4,975 MW MW MW 148 412 21 581 148 433 28 609 148 461 35 644 148 496 28 672 148 524 35 707 148 559 35 742 148 594 35 777 148 629 35 812 148 664 42 854 148 706 42 896 148 748 42 938 148 790 42 980 148 832 49 1,029 148 881 49 1,078 % 29% 29% 30% 29% 30% 30% 30% 30% 30% 30% 30% 30% Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 30% 30% 73 ANNEX II – SELF GENERATORS SURVEY (Prepared by Mr. John Cush, local consultant retained by GPL) Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 74 JOHN A. CUSH, FGAPE, MIEEE, MAWWA 20 Dandrade Street, Newtown Kitty, Georgetown. Tel./Fax: 592-225-2640 / 592-645-9923; e-mail: [email protected] November 17, 2009 Mr. W. Brassington Executive Director, National Industrial and Commercial Investments Ltd (NICIL), 126, Barrack Street, Kinston, Georgetown. Dear Mr. Brassington, RE: Self Generation Survey; - Final Report. Enclosed please find completed Final Report and Questionnaires for the above captioned. The report covers the Consultants findings during the survey period. As indicated in the report a number of barriers were encountered when conducting the Telephone survey. This no doubt contributed the Consultants inability to survey greater a number of the “small scale” user. I do hope you find this report satisfactory and should you require any clarification on any part of its contents please do not hesitate to contact me. Best regards. Yours sincerely John A. Cush Electrical Engineer Cc: Mr. M. Sharma – CEO (ag) GEA. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 75 SUMMARY This report seeks to present the findings of the Self-Generation (SG) Survey conducted by John A. Cush, Electrical Engineer there after referred to as the Consultant. The Consultant has been engaged by National Investment and Commercial Investments Ltd (NICIL) and the Guyana Power and Light Inc (GPL) to conduct a survey to verify the level of self generation presently employed in Guyana, given the fact that every person has the right to self generate. The methodology used to execute the survey was to: • Review the database supplied by the GEA with the intention to identify the Top Twenty listed organisations • Conduct site visits to the various operations at which self generation is predominant. That is mainly the so called “Top Twenty” industrial / commercial organisations which are self generating. • Conduct telephone interviews with other individuals and organisations listed in the database to verify the accuracy of the data. A specific set of questions were asked of the various operators relating to their generating activities. See questionnaire appended. OBJECTIVES The objective of the Survey is to; • Conduct a field verification of the SG database obtained from the Office of the Prime Minister • Update the said database • Establish the level of SG that is taking place. PROJECT CONCEPT. The Government of Guyana’s policy is that every person has the right to self generate. Therefore SG is allowed with no restrictions as far as all power is used for self consumption. Most of the SG organisations are industrial / manufacturing operations and units are usually matched to produce the power needs of the particular operation. As project planning of the Amaila Falls Hydroelectric plant progress it has become evident that there needs to be a through appreciation of the level of self generation which occurs. It is also necessary to know the total installed capacity and energy demand of the self generators. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 76 SURVEY RESULTS. The results of the survey to date indicate that most of the major manufacturing operations use their generators as a main power source. The main objective of implementing self generating facilities is to reduce cost related to energy resources and to overcome the frequent power outages. The results show that presently some 10.94 GWh is produced monthly by individual self generators. See appendix 2. This translates into annual generation of 131.28 GWh per year. This is a significant amount of energy. Self generation is mostly being used to secure reliable supply as a result of the inability of the GPL to supply and in some cases to reduce the cost of power during peak production hours. There are two clear groups of operators with GPL connections. The first group only use the GPL supply as a back up to their main source of supply and the second group obtains all or nearly all of their supply from GPL. The table appended deals strictly with operators who self generate either twenty four / seven (24/7) or those whom generate during the production cycle. The majority of the self generators are located along the East Bank of Demerara corridor which is an area in close proximity with the existing GPL grid. However as mentioned earlier most operators are off grid due to unreliability of power supply. A number of these operators have however expressed a desire to be reconnected on the GPL grid. The total installed capacity of the thirty six(36) listed companies is 59,933.7 kVA. Of the listed operators surveyed only two have indicated use of machines as standby units, meaning that they only use them in cases of emergency. All others utilise their machines as load demand necessitates. Thus in some cases all machines will be running or a combination of machines will be used. Further analysis of the installed capacity gives the following break down. See below table. Sector Fisheries Brewery/Distilleries Manufacturing Wood Products Hospitality Industrial- Metals Industrial – Gas bottling Number of Companies 7 2 9 4 4 5 Installed Capacity (kVA) 17,060 12,344 15,308 4,243.5 2,265 Percent of Total 29.2 21.68 26.2 8.14 7.26 3.88 1 1,000 1.71 4,755.5 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 77 Shipping Retail operations Services Totals: 1 1 2 750 464 243.7 1.28 0.79 0.42 36 58,433.7 100.0 The above table reveals that the manufacturing sector has the most self generators of the firms surveyed while the fisheries sector has the largest installed capacity. The Services has the least installed capacity. The table also shows that the fisheries, brewery/distilleries and manufacturing sectors account for the largest percentage of self generators. That is 44,712 kVA or 76 percent of the installed capacity. It is reported that the GPL has a total installed capacity of 125 MW. However within the thirty six (36) companies there are ninety four (94) individual generating units installed which have a combined total of 58,433.7 kVA or approximately 47 MW13. This is a significant amount of power since it is approximately 38 percent of the GPL installed capacity. The table below ranks the individual companies with respect to their installed capacity. Name of Company Installed Capacity (kVA) Demerara Distilleries Ltd. Prittipaul Investments Noble House Banks DIH Caribbean Containers Ltd Guyana Stockfeeds Ltd. Bev Enterprise Guyana Quality Sea Foods Sterling Products Ltd Barama Pegasus Hotel Edward Beharry & Co Ltd Buddy’s Princess Hotel Continental Industries E.C. Viera Investments BM Enterprise 8150 5,010 4,625 4,194 4,050 3,920 3,100 3,000 Percentage (%) of Installed Capacity 13.95 8.57 7.91 7.18 6.93 6.71 5.31 5.13 2,956 2,587.5 2,012.5 1890 1,876 1,300 1290 1025 5.06 4.43 3.44 3.23 3.21 2.22 2.21 1.75 13 Converted using a power factor of 0.8. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 78 Name of Company Demerara Oxygen Guyana Furniture Manufacturing Precision Woodworking John Fernandes Ltd. Trinidad Cement Ltd. (TCL) Industrial Fabrication Ltd. Giftland Office Max Triple Star Enterprises Parika Sawmills Popeyes Restaurant Caribbean Aviation Maintenance Services BASIF ECI Marlin Inc. Technical Services Inc. Supra International Inc. Single Seafood Loring Laboratories Namilco Germans Restaurant TOTALS: Installed Capacity (kVA) 1000 965 Percentage (%) of Installed Capacity 1.71 1.65 890 750 622 1.52 1.28 1.06 500 464 360 313 300 168.7 0.86 0.79 0.62 0.54 0.51 0.29 165 160 160 150 150 140 75 60 55 58,433.7 0.28 0.27 0.27 0.26 0.26 0.24 0.13 0.10 0.09 100..0 The table shows that thirteen (13) companies account for approximately 80 percent of the installed capacity of which one (1) company alone accounts for approximately fourteen (14) percent. The graph below show the grouping of the generators within the various sizes. The generators were grouped from under 100 kVA to over 900 kVA. The results show that out of the ninety (94) generators in excess of twenty five (25) are rated over 900 kVA. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 79 Installed kVA Rating of Major Self Generators Installed kVA 800 - 900 600 - 699 400 - 499 200 - 299 Under 100 0 5 10 15 20 25 30 Num ber of Generators The hours of operation varies between company to company. This is because some companies run their generators twenty four hours a day seven days a week (24/7) while others just run the generators during production hours. The chart below shows that 16 percent of the companies run their generators for a period of 160 hours within a given month while 31 percent run their generators for 720 hours within the month. Monthly Generation Hours 16% 27% 0 - 160 161 - 320 321 - 480 481 - 640 4% 31% 641 - 800 22% Average monthly fuel consumption varies significantly between the groups surveyed. Four (4) companies offered not to give any response to this particular request. Despite repeated request. Most companies reported using diesel fuel while only one company utilise heavy fuel oil. The Consultant also believes that there are significant errors in the reported fuel figures since most of the person who where answering the question were not quite certain as to the fuel consumptions. As a result the energy/ fuel ratio ( kWh/ gal) reported may not be a true representation of generator performance. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 80 Load supplied (reported) represents the load figures reported by the companies. As seen in the appended spread sheet some companies reported the load in various manners. Some reported in Amperes, kVA or kW. Also the majority of the figures given were average figures. The calculated14 load column shows the values computed taking into account the operating voltage of the various operations. In cases where the load value was given by the company that figure was used. For example the load reported by Precision woodworking is 350 kW thus this value was transferred into the calculated column. A similar situation exists with the reported energy consumption. Of the thirty six companies surveyed only four (4) of them have reported recording energy consumption. And as may be expected they are some of the major self generators. Those companies are DDL, Banks DIH, Caribbean Containers and Barama. However it has been noticed that there is a significant variation between the calculated energy consumption and the reported values. As a result of this discrepancy the Total Energy Generated varies between 10.94 GWh using calculated values or10.66 GWh using the reported figures in the computation of the total energy consumption. TELEPHONE SURVEY. The database used to conduct the entire survey contained some six hundred and twenty two (622) entries. Where each entry can be treated as equal to a generator. However in some cases it was found that for some entries the kVA rating consisted of the sum of a number of generating units. The Consultant was subsequently informed by staff from the Office of the Prime Minister that a waiver had been granted by the Prime Minister for the non-registration of generators rated less than 10 kVA. Taking this into consideration the original listing was then sorted by kVA rating in descending order. The sorted list produced 434 entries greater than 10 kVA out of the 622 entries. This then means there are some 188 entries between 0.1 and 9.9 kVA. In analysing the over 10kVA grouping it was found that approximately 20 percent self generate while the others used their units as a standby source. It was also found that there are a number of companies which have more than three (3) entries in the database. The companies found with multiple entries are; Power (Kw) = √3*V*I*pf; where V=voltage, I= amperes, pf =power factor. For 3phase operating systems. And P= V*I*pf for single phase systems. 14 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 81 Company Listed Number Duty Run Corrected number Guyana Telephone and 123 4 123 Banks DIH 21 3 14 Republic Bank 16 0 15 Edward Beharry & Co. 13 5 13 Delegation of European 12 0 11 9 0 6 194 12 182 Telegraph Co. Commission Gafsons Totals: The listed total in the above table represents approximately 45 percent of the over 10kVA generator population. However it should be noted of the 194 sets within the listed firms only12 or 6 percent of the units perform as duty sets apart from those mentioned earlier in this report. Also coming to light was that a number of units listed under these organisations are no longer in operation or have been replaced. Hence for the group listed in the above table the corrected numbers are 182 or 42 percent of the over 10 kVA group. There were also cases of duplicated entries. Apart from companies and organisations telephone verification was also sought from apparent listed individuals who have units registered. It should also be mentioned that during the telephone survey it was found that there are a number of so called “small” self generators. These are companies with less than 1 percent of the total installed capacity as shown in table 2 above. During the course of the survey a number of barriers were confronted. They are: ¾ Reluctance of some person to respond ¾ Unavailability of telephone numbers ( no listing, etc) ¾ Persons at home but cannot give details about the generator CONCLUSION The survey revealed the following; All companies surveyed are within grid areas Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 82 Monthly self generation estimated at 10.94 GWh Self generation installed capacity is in excess of 47MW or 38 percent of GPL installed capacity. Self generation is mostly used to secure reliable power supply There are a number of firms which are interested in having GPL connections. There are two clear groups of operators with GPL connections. The first group only use the GPL supply as a back up to their main source of supply and the second group obtains all or nearly all of their supply from GPL. A number of firms will like to see the cost of power reduced and reliability and quality improved. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 83 ANNEX I. SAMPLE QUESTIONAIRE. SELF GENERATION QUESTIONAIRE ______________ Name of Company: ……………………………………………….…... Company Address: …………………………………………………….. Company Representative: ………………………………………………… Contact Number: ……………………………… 1. How many generators does the company have? : …………….. 2. What is the rating (kVA) of the generator? : ……………………………….. 3. Is Generator used as Main source of Power or Standby? : ……………………… 4. What are the hours of operation per month? …………….. 5. What is the average monthly fuel consumption? : ……………………. 6. What is the type of fuel used?: ……………………………… 7. What is the Load supplied (kVA) ? : …………………… 8. What is the Energy Generated per month (kWh)? : ……………………… Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 84 Comments: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 85 ANNEX III – REVIEW OF EXISTING HYDROLOGY STUDIES Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 86 1. EXECUTIVE SUMMARY The design of Amaila Falls Project encountered several problems arising from the lack of hydrologic data. Therefore, the best techniques available were applied to cope with the lack of information but even so, several questions remained unanswered, such as the following: • The flows used were obtained by extrapolating the results from Kaieter Falls Station with different transfer coefficients and then adopting 0.30 without further justification. This may cause some uncertainty regarding the expected power generation. • The maximum flow adopted to design the dam was the result of transforming the Probable Maximum Precipitation value into the Probable Maximum Flow by adopting a C coefficient (Creaguer’s formula) that has no direct justification, thus causing uncertainty as regards the maximum flow adopted for the design at 5.010 m3/s. • In addition, the Probable Maximum Flood was assessed in the current basin status, with no deforestation or mining exploitation. Any modification of the basin in such respect will have an impact on the increase in the maximum value considered. • The flows assumed for different return periods, which set the maximum values to be adopted during the construction period, also include coefficients and parameters adopted without any actual data on the site. • In order to obtain more accurate information, it would be desirable to install a hydro-meteorological station in a section of the river that is representative of the Project. Even if the works start soon, the information obtained will always be useful and will allow future adjustment of the parameters necessary for operation. With respect to the studies conducted on the behavior of generation with different dam heights and installed capacities, it was concluded that: • Energy production is marked by hydraulicity in the different months of the year. In wet months (June to September), more power can be generated and demand is covered. • In months with low hydraulicity, demand is only partially covered. • The above shows the reservoir’s poor regulation, considering that in wet months or periods the surplus flows will be spilled. • As the reservoir level is increased (more regulation) or installed capacity is reduced, the percentage of demand coverage grows for the same load factor. • In the actual case, 140 MW at delivery point and maximum reservoir level at 462.00 m.a.s.l., the trend is confirmed: even with smaller load factors, there is a deficit in power generation in months with low hydraulicity. The potential increase in dam height will have little influence on the installed capacity due to the great existing fall, although it will improve annual power generation, considering the greater regulation capacity and the following features: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 87 • The increase in the maximum level from 462 to 468 m represents an increase of 26 % in the maximum height of Amaila Dam and 30 % in Kuribrong Dam, with major economic implications. • In addition to more investment, other aspects linked to the larger flooded area should be considered, in particular, associated environmental aspects. • Another alternative to enhance the dam’s regulation capacity, and therefore its annual average energy, could be the implementation of circular sector gates allowing some of the flows in wet months to be stored, thus reducing spilling. • It is considered, however, that this additional regulation capacity would be limited and equal to approximately only 10% of the annual spilling. • The convenience of installing gates to reduce the expected investment remains to be considered. 2. INTRODUCTION The review of hydrology studies included the following documents submitted by the Client: • Amaila Falls Hydroelectric Project – Guyana - Feasibility Study Report – Hydrology - Prepared by MWH – December 2001 • Amaila Falls Hydro - Estimated Monthly Energy and Average Power for a Range of Load Factors – Prepared by MWH – August 2009 • GEOTECHNICAL BASELINE REPORT FOR BIDDING Hydroelectric Power Project – Generating Facilities - June 2008 Amaila Falls • Amaila Falls Hydroelctric Project – Generating Facilities – Section 8 – Owners Requirement Drawings – June 2008 • PPA multiscenarioCovermemo_20090820.pdf 3. PROJECT DESCRIPTION Amaila Falls project is a conventional hydroelectric project, and the scheme includes two main dams located upstream of the confluence of the Kuribrong and Amaila Rivers, just above Amaila Falls. A 3 km long water conductor will divert approximately 50 m3 / sec of stream flow to the powerhouse, utilizing the available gross head of approximately 360 meters for electricity production. The proposed installed capacity is nominally 156 MW with four Francis units. At the normal maximum operating level of El. 462.0 meters, the storage reservoir would cover an estimated area of 26.7 square kilometers. The reservoir would contain a total storage volume of 180 million cubic meters (mcm), and of this total, 146 mcm would be considered usable for seasonal regulation and production of firm energy during the drier months. Operation to provide a reliable power source during the drier months will require a drawdown of the reservoir water level by a depth of up to 9.5 meters each year, followed by a refill in the subsequent wet months. The following major components are included in the Project: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 88 • Completion of access roads to the site, • Bridge across the Kuribrong River, • Two concrete-faced rockfill dams (CFRD), • A roller compacted concrete (RCC) overflow spillway, concrete stilling basin, and spillway channel • Intake structure and headrace tunnel, • Surge and power shafts, • Power tunnel (alternatively, a lower headrace tunnel and surface penstock) • Powerhouse with electrical and mechanical equipment, • Tailrace channel, • Switchyard with transformers and substation, and • Transmission line from the powerhouse to Linden and Georgetown. 4. SUMMARY OF KEY PROJECT FEATURES A brief summary of the key project features follows. 4.1. DAMS AND SPILLWAY Two dams are proposed for the Project, the Amaila dam and Kuribrong dam. An 850meter-long ridge connecting the Amaila and Kuribrong dams and has ground surface elevations varying from about El. 464 to El. 467 meters. Due to the maximum level of the reservoir of El. 464.8 meters, the ridge will require foundation treatment (i.e. grouting). As such, the ridge dam section will include low CFRD dams or a modified parapet wall. 4.1.1. AMAILA DAM The Amaila dam is located on the Amaila River approximately 250 meters upstream of the confluence with the Kuribrong River. The dam will be a concrete-faced rockfill dam (CFRD), is approximately 950 meters long (including the spillway), and has a maximum height of approximately 25 meters. A 2- meter-high parapet wall will be installed on the upstream side of the crest, which is 8-meters-wide and will serve as a two-lane access road. An overflow spillway will be constructed within the Amaila dam and will be constructed with RCC. The spillway is 237 meters long and has a crest elevation of 462 meters and maximum height of about 23 meters. The upstream face is sloped at 0.3H:1.0V (horizontal:vertical) and the stepped downstream face is sloped at 0.8H:1.0V. The downstream face transitions into a 40-meter-long stilling basin and is then channeled back into the Amaila River channel. The spillway includes a 4-meter-wide bridge deck supported on piers. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 89 4.1.2. KURIBRONG DAM The Kuribrong dam is located on the Kuribrong River approximately 1.5 kilometers upstream of the confluence with the Amaila River. The CFRD, is approximately 850 meters long, and has a maximum height of approximately 20 meters. A 2-meter-high parapet wall will be installed on the upstream side of the crest, which is 8-meters-wide and will serve as a two-lane access road. 4.2. INTAKE AND HEADRACE TUNNEL The intake structure is located approximately 120 meters upstream of the left abutment of the Amaila dam. The intake consists of a 145-meter-long approach channel, flared inlet, and gate structure. The gate structure is 20 meters high constructed of reinforced concrete, and is equipped with a trash rack, trash rake, hydraulic intake gate, and a stoplog. It is presumed that the intake tunnel. The headrace tunnel tunnel and sloped toward the supported with a combination sets. The tunnel will be lined conditions encountered. 4.3. will be used as a portal for constructing the headrace is a 1,600-meter-long and 4.7-meter-wide D-shaped powerhouse at about 1.5 percent. The tunnel will be of reinforced shotcrete, rockbolts, concrete, and steel with shotcrete of concrete depending on the geologic SURGE AND POWER SHAFT A 7.0-meter-diameter surge shaft will be excavated from the ground surface to the headrace tunnel. The shaft will be supported near the surface with a shaft collar and with systematic rockbolts and reinforced shotcrete below. The surge shaft includes a 50-centimeterthick concrete lining. A 20-meter-high above-grade surge tank will aid in system governing. A 4.1-meter diameter power shaft will extend below the headrace tunnel to the minimum invert elevation of El. 110 meters. The shaft will be supported with systematic rockbolts and shotcrete. The surge shaft will have a 30-centimeter-thick concrete lining. Alternatively, the power shaft will extend to about El. 345 meters, and connect to a short lower headrace tunnel segment. 4.4. POWER TUNNEL The power tunnel is a 1,230-meter-long and 4.7-meter-wide D-shaped tunnel. In the lowest acceptable water conductor profile, the power tunnel extends from the base of the vertical power shaft at minimum El. 110 meters to the bifurcation at the powerhouse at a slope of approximately 1.5 percent. The tunnel will be supported with a combination of shotcrete, rockbolts, concrete, and steel sets. The tunnel will be finished to a circular cast-in-place concrete-lining or steellining with concrete backfill section. 4.5. LOWER HEADRACE TUNNEL AND SURFACE PENSTOCK ALTERNATIVE A lower headrace tunnel and surface (buried) penstock, is an alternative water conductor connecting the power shaft to the powerhouse represents the highest Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 90 acceptable water conductor profile. The lower headrace tunnel is a 300-meter-long and 4.7-meter-wide D-shaped tunnel extending from the power shaft at about El. 345 to a portal below the face of the escarpment. The tunnel will be supported with a combination of reinforced shotcrete, rockbolts, concrete, and steel sets. The finished tunnel will be circular and be concrete-lined or steel-lined with concrete backfill. The cut-and-cover steel penstock is approximately 1,040 lineal meters and has an inside diameter of approximately 3.1 meters. The penstock pipe will be constructed in an open-cut earth or rock trench or supported on compacted rock fill, installed on a layer of bedding material, and buried with compacted sand and rockfill. Anchor and thrust blocks will be needed at locations where there are significant changes in the vertical or horizontal alignment. 4.6. POWERHOUSE The powerhouse is located in an area along the left bank of the Kuribrong River in which it is expected that the powerhouse will be founded entirely on sound rock. The partially buried powerhouse will be an enclosed structure with a reinforced mass concrete substructure, steel and concrete superstructure, and a sloping, trusssupported roof. The powerhouse is approximately 27-meters-wide by 51-meters-long, with a maximum height of about 34 meters. Each of the four units has an installed capacity of 39 MW. 4.7. TAILRACE CHANNEL The tailrace channel is 36 meters-wide at the base, 110-meters-long, and has a maximum depth of 13 meters. It will be excavated through overburden and boulders and bedrock before connecting to the Kuribrong River. The channel will be both unlined and lined with concrete and rip rap, to a finished elevation of approximately 96 meters. 4.8. SWITCHYARD The switchyard will be constructed immediately northwest of the powerhouse. The electrical substation will be constructed on the pad having a finished elevation of 108 meters and connect to the transmission line. The switchyard pad will be constructed on bedrock and compacted rock fill and is approximately 75 meters wide and long. 4.9. KURIBRONG BRIDGE The Kuribrong Bridge is located approximately 100 meters downstream of the powerhouse and will serve as a permanent access to the powerhouse area. The bridge is approximately 120 meters long and capable of safely transporting the single largest and heaviest piece of construction or permanent equipment transported on site. The abutments will be founded on bedrock and have a minimum underside elevation of 108.5 meters. 5. HYDROLOGY ASPECTS Information on hydrology is the foundation of any hydroelectric project, as it provides key information for different major aspects of design, economic assessment and security related aspects such as: design flow for diversion works; mximum flow to be Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 91 controlled by the reservoir and to be released by the spillway; mnimum distribution flow for environmental requirements; reservoir operation rules; energy that can be generated for different conditions; reservoir evaporation and reservoir sedimentation. The reference study to obtain hydrology design parameters for Amaila Falls was developed by MWH (Montgomery Watson Harza). The basin contributing to Amaila Falls is defined by those of the Amaila and Kuribrong Rivers, but no hydrologic information on either river has been collected on site for a considerable period of time (1979-1989). Therefore, some important office work has been performed by using the information available, and this has helped to generate the hydrology to be used in the project. 5.1. SITUATION OF AMAILA PROJECT The hydrology situation of Amaila Falls was analyzed from the existing information in the document prepared by MWH. The Amaila Dam is located in the central western part of Guyana, immediately upstream of the confluence of the Kuribrong and Amaila Rivers. After receiving the contribution of the Amaila River, the Kuribrong River flows west for about 90 km and joins the Potaro River, downstream of Kaieteur Falls. The Potaro River, on the other hand, joins the Essequibo some 30 km downstream of its confluence with the Kuribrong. The Essequibo flows north into the Atlantic Ocean 35 km northwest of the country’s capital city, Georgetown. 5.2. TOPOGRAPHY AND CONTRIBUTING BASINS DRAINAGE The total area of the Amaila and Kuribrong Rivers contributing basins is 648 Km2, 119.4 Km2 of which correspond to the Amaila River. In the confluence area, vegetation is very thick and generates strong resistance to runoff. The Kuribrong River starts at 670 m.a.s.l., runs southwest for 21 Km, and then turns north. The total slope of the river until reaching the foot of the dam is 350 m. The river’s Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 92 longitudinal slope is 2.42 m/Km up to 50 Km upstream of the dam whereas at the head the slope is 0.73 m/Km. As for the Amaila River, it starts at 610 m.a.s.l. and flows east to the confluence with the Kuribrong. The bottom slope in the dam area is 2.56 m/Km whereas at the head the slope is 38.1m/Km. 6. OBTAINING THE RESERVOIR’S HYDROLOGY PARAMETERS 6.1. DETERMINATION OF AVERAGE MONTHLY AND ANNUAL FLOWS The annual periods surveyed were analyzed with data from the gauging stations in the area; their proximity was also examined in connection with the location chosen for the projected dam. Thus, the station on the Potaro River near Kaieteur Fall was selected as the most representative. It has a 41-year record of average daily flows (1950-1990) with some information gaps between 1979 and 1989. The basin’s drainage area at the control point is 2797 m2. These recorded average daily flows helped to obtain the average monthly and annual flows – both maximum and minimum - in that station. By means of statistical inference and the use of the HEC-4 program (US Army), the missing data series between 1979 and 1989 was completed. Since the gauging results were obtained at the Potaro River, it was necessary to extrapolate them by means of coefficient 0.3 to transfer them to the dam’s location. The coefficient was obtained from data on the Kuribrong River and results were compared with the data from the gauging station on the Potaro from December 2000 to August 30, 2001. An average value of 0.352, with a minimum of 0.182 and a maximum of 1.825, was obtained from the relation between the flows surveyed on the Kuribrong River and the hydro-meteorological data measured at the station on the Potaro in the surveyed period. A gauging study conducted on the Kuribrong River in June-July 1975 was considered as background information. There were 22 measurements which resulted in an average relation between flows of 0.30. The use of a value of 0.26 was suggested, considering the thicker vegetation on the Kuribrong River basin and an area relation of 0.23 between basins. A value of 0.30 was used as transposition factor for this study. It was deemed adequate considering the results obtained. This factor was applied on the hydrometeorological flows measured on the Potaro River near Kaieteur Fall. By means of this procedure, an estimated average flow of 64.1 m3/s was obtained; maximum and minimum flows were estimated at 210.1 m3/s and 4.5 m3/s. The results are shown in the following graph: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 93 Monthly Streamflow - Kuribrong River downstream to the Amaila falls site 225,0 Monthly Mean Streamflow Monthly Maximum Streamflow 200,0 Monthly Minimum Streamflow 175,0 Flow Q [m3/s] 150,0 125,0 100,0 Qm = 64,1 m3/s 75,0 50,0 25,0 Dec Nov Oct Sep Aug Jul Jun May Apr Mar Feb Jan 0,0 Month - Period of Record [1950 - 1990] The following graphs show the probabilities of flows being equal or greater in the different months surveyed, considering the period between 1950 and 1990. [January - June] - Percent Time Discharge Equalled or Exceeded - [Períod of Record 1950-1990] 350 January 325 February 300 March April 275 May 250 June Flow Q [m 3/s] 225 200 175 150 125 100 75 50 25 0 0,00 10,00 20,00 30,00 40,00 50,00 60,00 70,00 80,00 90,00 100,00 Percent [ %] Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 94 [July - Dicember] - Percent Time Discharge Equalled or Exceeded - [Períod of Record 1950-1990] 275 July 250 August September 225 October November 200 Dicember Flow Q [m 3/s] 175 150 125 100 75 50 25 0 0 10 20 30 40 50 60 70 80 90 100 Percent [ %] 6.2. RESERVOIR EVAPORATION In order to determine reservoir evaporation, the data obtained from the gauging station at Kaieteur Fall, with a 17-year record from 1959 to 1975, was considered. Average gross evaporation in the reservoir was 1546 mm a year. The minimum monthly value was 63 mm and the maximum was 201 mm. To obtain net evaporation, reservoir evaporation was considered to be 75% of gross evaporation and this was compared to the accumulated precipitation for all relevant months. The results show an annual net evaporation value of 629 mm. The graph with the results obtained is shown below: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 95 Monthly Net Evaporation - Amaila Falls Basin Annual Net Evaporation = 628 mm Net Evaporation 120 Lake Evaporation Evapotranspiration Evaporation [mm] 100 80 60 40 20 6.3. Dicember November October September August July June May April March February January 0 PROBABLE MAXIMUM FLOW – OPERATION PERIOD The flow of the probable maximum flood was estimated from the probable maximum precipitation (PMP). The procedure included an assessment of the following items: estimation of the PMP; duration of the PMP; temporal distribution of the PMP; losses due to infiltration; unitary diagram; transformation of PMP into Probable Maximum Flow and evaluation of the Probable Maximum Flow. 6.3.1. ESTIMATION OF THE PMP In order to estimate the PMP value, a method proposed by Hershfield in 1965 was used, with the following equation: X m = X n + KmSn Xm = Maximum Precipitation Xn = Average Precipitation of annual maximums in a 24-hour series Sn = Standard Deviation from annual maximums in a 24-hour series Km = Statistical Variable The variables in the equation above were estimated by using the data on daily precipitation obtained from the gauging station at Kaieteur Fall, with a record from 1953 to 1977, and the data from Kamarang station, with a record from 1955 to 2000. The PMP results for each of these stations were 693 mm and 389 mm. The average of the two stations, after applying a reduction coefficient of 0.89 for the drainage area, was therefore considered to be an adequate value. The PMP value was then 481 mm. 6.3.2. DURATION OF THE PMP A 24-hour duration was considered adequate, considering topography, slopes, and rainfall regimes. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 96 6.3.3. TEMPORAL DISTRIBUTION OF THE PMP The temporal distribution of the PMP was based on a study conducted by Persaud and Forsythe (1980) showing rainfall disaggregation for a Tr = 100 years, for storms lasting between 5 minutes and 12 hours. With this data, duration vs. intensity curves were calculated by using the rainfall data from the Kaieteur Fall station. In order to obtain the disaggregation of the PMP for 24 hours with a 1-hour discretization, disaggregation factors published by the WMO (World Meteorological Organization) were used. The results are shown below: Time Distribution of PMP 175 165 150 125 Precipitation [mm/h] 115 100 75 50 40 35 30 20 25 3 3 3 3 3 4 4 5 5 5 1 2 3 4 5 6 7 8 9 10 10 5 5 4 4 3 3 3 18 19 20 21 22 23 24 0 6.3.4. 11 12 13 14 15 16 17 LOSSES DUE TO INFILTRATION The process of losses due to infiltration can be split into two stages: initial infiltration, which takes into account vegetation interception, soil depressions, and lack of soil humidity, and a uniform type of infiltration, which considers the soil’s natural percolation capacity during storms and after the initial infiltration has taken place. Considering that the PMP represents the maximum probable precipitation, it seems adequate to disregard initial losses due to infiltration, whereas in the case of uniform infiltration, a type C soil (SCS. 1972) was considered, with a value of 3mm/hour. 6.3.5. UNITARY DIAGRAM Since two different rivers flow into the site where the dam has been projected, two different hydrograms apply, pursuant to the characteristics of each basin. Therefore, the procedure used to define the hydrogram for the Amaila and Kuribrong Rivers consisted in the transposition of the hydrogram of the Caroni River in Venezuela, the basin of which is adjacent to that of the Kuribrong. This hydrogram was obtained in a section with similar characteristics (divided basins). The base flow was defined as the maximum monthly flow with a value of 219 m3/s, where 40 m3/s corresponded to the Amaila and 179 m3/s to the Kuribrong, pursuant to the relation of the contribution areas. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 97 Unit Hyrograph - Amaila River Subbasin and Kuribrong River Subbasin 10 HU Amaila HU Kuribrong Streamflow [m3/s] 8 6 4 2 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 Hours 6.3.6. TRANSFORMATION OF PMP INTO PMF The rainfall-flood transformation was performed by using HEC-1 software, with the input of the following data: drainage areas in each sub-basin; base flow for each subbasin; PMP with 24-hour duration; temporal distribution of PMP; losses due to infiltration; percentage of wetlands; unitary hydrogram for each basin. The hydrology modeling resulted in the composition of the Amaila and Kuribrong Rivers hydrograms, with a peak flow value of 5010 m3/s and an accumulated volume of de 314 Hm3 after three-day floods. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 98 6.3.7. EVALUATION OF THE PMF Results were evaluated by estimating coefficient C in Creaguer’s formula: Q = 1.303 C (0.386 A) 0.936 A −0.048 Where: Q is the peak flow in m3/s and A is the drainage area in Km2. Results show a value of C = 87, whereas the value of C for the Caroni River in Venezuela was 127. Past experience shows that the values of C can vary between 80 and 100. 6.3.8. MAXIMUM DESIGN FLOW DURING THE CONSTRUCTION PERIOD The values of maximum daily flows were obtained from the data provided by the hydrometeorological station at Kaieteur Fall on the Potaro River from its records between 1950 and 1990, while the missing data was obtained by statistical inference. The calculation procedure consisted in allocating recurrences from the series of data obtained and later assigning a probability adjustment curve that can adapt to data distribution. The distribution curves used were the Generalized Extreme Values curve and Log Pearson Type III, with adequate adjustment for recurrence periods of less than 50 years in both cases. For longer recurrence periods, the curves showed less probable values. Therefore, it was necessary to obtain the values of peak flows for the construction period based on the precipitation data obtained from Kamarang and Kaieteur meteorological stations. Once the maximum daily precipitation data had been obtained, the same adjustment procedure was applied by means of a Log Pearson Type III to obtain the precipitation values for 2, 5, 10, and 25 years of recurrence by applying the corresponding reduction coefficients by area, which were 55, 62, and 68%, respectively. Later, the precipitation to flood transformation was performed by using HEC-1 software, considering the same input used to calculate the Probable Maximum Flow, except for the modification in the rainfall data, but with the same rainfall distribution and the same unitary diagrams. The results obtained show the peak flow and the accumulated volume for each recurrence: Flow Tr Precipitation Peak Accum. Volume [year] [mm] [m3/sec] [Hm3] 2 5 10 25 50 100 200 500 1000 97 120 134 153 166 180 194 212 227 708 969 1128 1339 1486 1646 1880 2077 2240 49.1 65.6 75.6 89.1 98.4 108.8 123 136 146.3 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 99 Flood Peak [Qp] vs Return Period [Tr] 1000 500 2250 200 2000 100 1750 Streamflow [m 3/s] 50 1500 25 1250 10 1000 5 750 2 500 250 Flood Peak vs Tr 0 0 200 400 600 800 1000 Return Period [years] 7. SEDIMENTATION A sedimentation value of 0.25 mm/year was estimated on the basis of preceding studies on the Caroni River in Venezuela, near the Kuribrong River basin. Considering the same sediment transportation for the Kuribrong River, an accumulation of 0.165 Hm3/year was determined, which seems insignificant compared to the estimated storage capacity of the reservoir: 180 Hm3. This is confirmed when the thick vegetation in the area is considered, which acts as a green lung to control both surface runoff and sediment transportation, and the lack of mining exploitation in the analyzed area. 8. CONCLUSIONS ON HYDROLOGY ASPECTS The hydrology study conducted by MWH for the Amaila Falls Project encountered several problems arising from the lack of actual information on the project site. Because of this lack of information, MWH applied the best available techniques, extrapolating results from similar neighboring basins to fill in the existing information gaps. Although the adopted methods are the most adequate and reasonable for this type of processes marked by the lack of direct hydro-meteorological information, the results obtained present some uncertainties that are typical of the situation and which may be summarized as follows: • There is no hydrologic information available on the section where the Amaila Dam will be built. The flows considered were obtained by extrapolating the results from Kaiefeur Fall station, and may cause certain doubts as to the calculated power generation. The transfer factor was modified at different stages in the study and reached the value of 0.30 used in 2001. There is not much justification for this coefficient. • In this respect, reliable records in Potaro River station cover the period 19501990, as stated in MWH’s report. This does not include the last 19 years. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 100 • On the other hand, the maximum flow adopted to design the works was established by transforming the PMP into PMF. Coefficient C is also used for this transformation, by applying Creaguer’s formula, which has no direct justification in the analyzed basin. It is even mentioned that the value is 127 for the Caroni basin, used as a reference due to its proximity to the analyzed basin, whereas the value adopted for Amaila was 87, and a reasonable value would range between 80 and 100. This causes uncertainty and may lead to an increase in the maximum flow adopted for the design at 5,010 m3/s. • In addition, it should be mentioned that when assessing the PMF, the basin was considered in its current state, with no deforestation or mining exploitation. Any modification of the basin in this respect will have an influence on the increase in the maximum value considered. • On the other hand, the flows assumed for different return periods, which set the maximum values to be adopted during the construction period, also include coefficients and parameters adopted with no actual data on the site, and introduce certain doubts as to the parameters to be considered during the works. • It is recommended to set up a hydro-meteorological station in a section of the river that is representative of the Project, as close as possible to the site, in order to obtain more accurate information. Even if the works start soon, the information will always be useful and will allow adjusting hydrology parameters in future. 9. DAM HEIGHT AND INSTALLED CAPACITY In order to evaluate different alternatives for the height of the dam and its installed capacity, MWH conducted an evaluation of the monthly energy and average capacity for a range of load factors from 50 to 100%. The analysis is based on historical hydrologic data, which indicates the monthly and annual energy that the Project can generate. To estimate the flows of the Kuribrong River, the available data on the neighboring basin (Potaro River) was multiplied by a transposition factor (0.3), as described in the feasibility study. The hydrology record goes from 1950 to 1990 (41 years of monthly flow data). Current monthly flow data is not available for analysis. The data was taken from the report included in the feasibility study for Amaila Falls Hydroelectric Project from December 2001 (and later update) and is subject to the limitations described. Two maximum reservoir levels were considered for the situations described above: 462.0m and 468.0m. Power generation estimations assume that the power house operates with 96% availability (the model implies a 4% level for scheduled and forced cutoffs) and is based on an annual peak of output power depending on the load factor and the given scenario. The monthly energy demand was evenly distributed in proportion to the number of days in the month. Power generation is therefore mainly based on demand requirements, subject to the availability of incoming flows and to the water stored. 9.1. METHODOLOGY Reservoir operation was chronologically simulated on a monthly basis for the 492 months in the series as follows: Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 101 • In wet months, the reservoir is filled or remains full and the maximum possible power is generated until reaching a limit defined as estimated demand, based on peak capacity for a given load factor. Any extra flow is spilled or (if possible) stored in the reservoir. • In dry months, the plant is operated to meet the target demand. Therefore, the net incoming flow is supplemented by using water from the reservoir to meet demand until the minimum operation level is reached. • Different types of hydrology years have been considered pursuant to the definition of flows in the hydrology report, considering the following: 9.2. - Mean years, corresponding to a mean monthly contribution of the hydrology series considered - Minimum hydrology years, corresponding to the minimum monthly contribution of the hydrology series considered - Years exceeded 90% of the time as to the monthly contributions considered. RESULTS The following graphs show the results obtained, based on demand coverage percentages for the different load factors adopted. For each of the situations considered, dam height and installed capacity, the graphs will show the minimum value (that it is exceeded 90% of the time), and the mean value. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 102 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 103 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 104 Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 105 The following conclusions on the behavior of the dam are drawn from the analysis of the graphs above: • Energy generation is marked by hydraulicity in the different months of the year. In wet months (June to September), more power is generated and, in general, demand is covered. • On the contrary, in months with low hydraulicity, demand is sometimes only partially covered. • This shows little reservoir regulation, considering that in wet months or periods it has no reservoir capacity and spills surplus flows. • The design contemplates only one of the 4 cases considered, corresponding to 140 MW supplied capacity and a maximum reservoir level of 462.00 m. • As usual, it is shown that as the reservoir level increases (more regulation) or installed capacity decreases, the percentage of demand coverage grows for the same load factor. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 106 • In the abovementioned case, corresponding to the actual project, it is confirmed that, even with lower load factors, there is a deficit in power generation during the months with the least hydraulicity. 10. POSSIBILITIES OF DESIGN VARIATIONS: GENERAL COMMENTS The project design has few possibilities of modification, considering that it is based on all the available information and any possible enhancement should necessarily require additional field studies. 10.1. INCREASE IN DAM HEIGHT The increase in dam height is connected with the possibility of generating more power due to the greater useful head, while enhancing reservoir regulation and reducing the number of months with energy deficit. Topographical, geotechnical and environmental conditions could affect the height of the dam, limiting the possibilities of increasing it. The increase in dam height will not have much incidence on the capacity generated by the hydroelectric plant, considering that the useful head is about 360 m and any increase in dam height would only allow for a few more meters of useful head: • For instance, for every 3.6 m increase in reservoir level, an increase of 1% in installed capacity would be obtained, which is irrelevant considering hydrology uncertainties or even transmission losses. • It should be considered that a 3.6 m increase in the crown level would require a 14.4% increase in the maximum height of the Amaila Dam and an 18% increase in the maximum height of the Kuribrong Dam. Since the dams have major longitudinal development, the elevation of the crown level will likely cause substantial increase in the cost of the works. • Increasing maximum height from 462 m to 468 m would imply increasing the height of the dam by 6 m, and consequently an increase of 26% in the maximum height of the Amaila Dam and 30% in that of the Kuribrong Dam. • Regardless of the economic incidence of this increase in dam height, there are a number of aspects that should be considered in connection with the larger flooded area and, in particular, associated environmental aspects. 10.2. ENHANCING THE DAM’S REGULATION CAPACITY The use of a free spillway working without any control when the reservoir reaches 462.00m can be modified to increase its regulation capacity by installing gates to control the levels and store surplus flows in wet months to be used in dry months. The required modifications could be the following: • Reduction in the level of the spillway lip to, for example, 457.00 m. • Reduction in the width of the spillway to some 40 m in order to maintain its regulation capacity. • Implementation of circular sector gates allowing flows in wet months to be stored and not spilled. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 107 • Adoption of reservoir operation rules allowing for adequate protection of the necessary volumes to store flood flows. The possibility of including these modifications will have two effects. 1. On the one hand, the resulting final cost could be smaller, mainly due to major reduction in the volume of the RCC dam when the length and height are reduced. An additional cost will be the installation of gates, the intermediate piles, and the solution of associated structural problems. Pursuant to the current Project, flood flows are automatically regulated without the operator’s intervention, as the spilling begins by mere overflowing without human action when the reservoir level is reached. 2. On the other hand, with reference to reservoir regulation and considering that annual spilling in an average year is around 2.000 hm3, the regulation volumes that can be obtained (no more than 200 hm3, in any case) indicate that it is not feasible to enhance reservoir regulation in a substantial manner, considering that the available volume would only be 10% of the average annual spilling. The evaluation of this solution must contemplate the need to operate the reservoir gates to control floods, as failure to do so may cause dam overtopping and associated damage. The following aspects should be considered: • The need to have permanent control over the position of the spillway gates and the reservoir levels. • Alternative power supply to operate the gates, both externally and locally, by means of on-site ancillary generation. • Gate maintenance tasks. Economic and Financial Evaluation Study: Guyana - Amaila Falls Hydro Project 108
© Copyright 2026 Paperzz