Appendix N – CHP
Assessment
1
Seabank 3
CHP
Assessment
April 2014
47064101
Prepared for:
SSE Seabank Land
Investments Ltd
UNITED
KINGDOM &
IRELAND
Seabank 3 Combined Heat and Power Assessment
REVISION SCHEDULE
Rev
Date
Details
Prepared by
Reviewed by
Approved by
0
17/01/14
Draft for
Comment
Veronica Hamilton
Rob Boyer
Oliver Riley
Senior Energy Engineer
Principal Engineer
Technical Director
Final Draft
for PEI
Veronica Hamilton
Rob Boyer
Rob Boyer
Senior Energy Engineer
Principal Engineer
Principal Engineer
1
04/03/14
URS Infrastructure & Environment UK Limited
6-8 Greencoat Place
London
SW1P 1PL
United Kingdom
www.urs.com
www.urscorp.com
CHP ASSESSMENT
April 2014
Seabank 3 Combined Heat and Power Assessment
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TABLE OF CONTENTS
1
2
3
4
5
6
7
8
EXECUTIVE SUMMARY ................................................... 1
INTRODUCTION ................................................................ 3
PLANNING CONTEXT ...................................................... 5
OBJECTIVES AND APPROACH .................................... 10
HEAT DENSITY ANALYSIS............................................ 12
CHP ANALYSIS............................................................... 25
TECHNICAL AND COMMERCIAL CONSIDERATIONS 27
CONCLUSIONS ............................................................... 30
ANNEX A – SITE LOCATION ............................................................ 32
ANNEX B – IDENTIFIED HEAT LOADS ........................................... 33
ANNEX C – CHP-R ASSESSMENT FORM ...................................... 37
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1
EXECUTIVE SUMMARY
This Combined Heat and Power (CHP) feasibility study has been prepared in support of an application
for a Development Consent Order (DCO) for the proposed Seabank 3 generating station. The Proposed
Development will provide up to 1,400 megawatts (MW) electrical generating capacity alongside the
existing Seabank 1 & 2 power station.
This study has been produced in accordance with the requirements of the NPSs EN-1, EN-2 and the
EA’s CHP Ready Guidance, national and regional planning policies to evaluate the heat demands in the
area of the Proposed Development in order to assess the potential for heat recovery.
The following sources have been consulted in order to identify potential existing and future core heat
loads:
•
•
•
•
•
The National Heat Map;
CHP Database and District Heating (DH) installation map;
Planning applications in the surrounding area;
Information available from local authorities; and
GIS data and benchmarking exercises.
This process identified 18 existing and 3 potential heat consumers within reasonable distance to the
Proposed Development Site, of which two, Astra Zeneca and the Western Approach Distribution Centre,
have been recognised as having some potential for connection to a district heating system. With the
exception of the these two developments, there are predominantly only light industrial facilities in
reasonable proximity to the Proposed Development Site, which URS would not consider individually or
collectively to offer suitable viability to become customers of a successful DH network at this time.
In addition to the low heat demands in the area, the Severnside Energy Recovery Centre is immediately
adjacent to the Proposed Development Site and is currently under construction, with an anticipated
commissioning date of 2016. It is understood that this Energy Recovery Centre will not be providing
heat to surrounding developments, which suggests that no appropriate heat consumers could be found
by its developer. The Energy Recovery Centre is of a smaller scale compared to the Proposed
Development (circa 20 to 30 MWe), which is likely to be more compatible with the scale of heat
demands that have been identified in the area, if a heat network were to become viable.
A number of other energy recovery centres have been identified within 1km of the Proposed
Development Site which would also be better placed to export heat to local users, further reducing the
potential for the Proposed Development’s provision of CHP. These energy recovery centres would
provide a more appropriate heat source due to their continuous generation compared to the Proposed
Development, which will be more intermittent and unreliable. This would reduce the available heat loads
in the area
In conclusion, although the plant could provide significant volumes of heat when operating, given the
anticipated intermittent operating regime for the proposed development, it is not considered that a CHP
solution would be viable without significant additional back-up heat production. Additionally, heat
mapping studies that have been carried out indicates there is no significant density of heat demand
currently available in reasonable proximity to justify the development of a heat network. For those heat
loads that have been identified, or may become available in the future, it is considered likely that these
would be more effectively supplied by the smaller scale energy facilities already proposed, consented
and/or under development within 1km of the Proposed Development Site
Despite these initial findings, the Applicant will ensure that the Proposed Development is designed to be
‘CHP Ready’ and will carry out an on-going review of CHP potential, including:
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•
•
•
•
Maintaining a dialogue with heat users already approached;
Setting up a working group involving all key stakeholders to maintain momentum;
Carrying out an annual reviews to determine if there have been sufficient changes in
circumstances to warrant a new technical and financial review; and
Re-visiting the technical and economic assessments at least every 5 years or when a change in
circumstances warrants.
The above will be been incorporated into a Requirement contained within the draft Development
Consent Order.
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2
INTRODUCTION
2.1
URS has been commissioned by SSE (the ‘Applicant’) to undertake a Combined Heat and
Power (CHP) Feasibility Study for the proposed Seabank 3 generating station (hereafter
referred to as the Proposed Development).
2.2
The Proposed Development Site (the Site) is located in Severnside, near Bristol, adjacent
to the existing Seabank Power Stations (Seabank 1 & 2). The Proposed Development Site
is entirely within the administrative area of South Gloucestershire Council (SGC), although
part of the DCO Site for offsite Associated Development (a cooling water pipeline and
electrical connection) falls within Bristol City Council (BCC).
2.3
The Proposed Development will comprise one or two combined cycle gas turbines (CCGT)
up to 1,400 Megawatts electrical (MWe) output plus up to two peaking plant units that will
be up to 240 MWe. The total capacity of the generating station will not exceed 1,400 MWe.
2.4
This study evaluates the heat demand in the area of the Site, so that the potential for heat
recovery from the Proposed Development can be assessed.
2.5
This document has been produced in accordance with the requirements of National Policy
Statements (NPSs) EN-1, EN-2, and the Environment Agency’s (EA’s) CHP Ready
Guidance, the national and regional planning policies in order to support an application for
a Development Consent Order (DCO).
Principles of Combined Heat and Power and District Heating
2.6
A Combined Heat and Power (CHP) system generates electricity while also providing
useable heat from the same process. The useable heat can be recovered from parts of the
electricity generating process, such as the cooling or flue systems, where it may otherwise
be lost to the environment. This can provide a more efficient energy generation system
compared to traditional power-only CCGT generation systems, with the potential to
improve typical gross efficiencies of modern plants from 55-60% to in the region of 75-80%.
2.7
For a CHP system to be viable, appropriate heat consumers in suitable proximity to the
heat source are required. Heat consumers could be in the form of a single user, which at
this scale would typically be a large industrial process user, or a number of smaller
consumers forming part of a District Heating (DH) system.
2.8
DH systems comprise of a network of pre-insulated pipes carrying hot water or steam from
one or more centralised heat generating sources to a number of consumers. The hot water
or steam is then typically used for process uses, space heating or Domestic Hot Water
(DHW) generation, depending on the requirements of the consumer. District heating
systems can deliver benefits to consumers by providing a low carbon source of heat in a
more efficient manner than may be achievable through single buildings adopting individual
measures, as well as reducing the plant and space requirements on-site, which in turn can
provide capital and on-going maintenance and energy cost savings.
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Description of the Proposed Development
2.9
The Proposed Development is adjacent to the existing Seabank 1 & 2 station,
approximately 5 km northeast of Avonmouth and 10km northwest of Bristol in an area
called Crooks Marsh in Severnside.
2.10
The Proposed Development Site is located within SGC but its southern boundary forms the
BCC administrative area. The proposed associated development of the electrical
connection and cooling water pipeline lie in BCC.
2.11
Surrounding developments are in the majority industrial in nature with Severn Beach,
Hallen, Pilning and East Compton communities located several kilometres away. Annex A
– Site Location provides a map of the area.
2.12
The Proposed Development comprises up to 1,400 MWe of generating capacity based on:
one or two natural gas-fired CCGTs with a generating capacity of up to 700 MWe each;
and natural gas-fired peaking plant units with a generating capacity of up to 240MWe. The
peaking plants will be designed to ‘black start’ on distillate fuel in the event of failure of the
UK electricity grid, to help enable restart of the grid. The peaking plant will also provide fast
response ‘top up’ supply to the grid during peak periods, to support the development of
renewable generation on the UK national grid.
2.13
The Proposed Development will be able to operate 24 hours a day, 365 days a year.
However due to the predicted demand, it is anticipated that the CCGTs will operate at an
average 31% load (an average 2,716 hours per year) over the course of its lifetime, with
the peaking plant limited to approximately 17% load (a maximum 1,500 hours a year). The
power generation will therefore be both irregular and intermittent.
2.14
Although adjacent to the existing Seabank 1 & 2 station, the Proposed Development is
being progressed independently, with some shared services including gas supply, cooling
water electrical connections and access.
2.15
Due to the scale of the Proposed Development it is being made Carbon Capture Ready
(CCR), such that it will be ready for any potential future application of Carbon Capture and
Storage technology, as per the requirements set out in the EU Carbon Capture and
Storage (CCS) Directive and associated DECC CCR Guidance, though any such
development would be made under separate consent and is therefore outside the scope of
this DCO Application. Nevertheless, in accordance with the CHP-R guidance, an
assessment has been made of the CHP and Carbon Capture envelope for the Proposed
Development, as presented in Annex C – CHP-R Assessment Form.
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PLANNING CONTEXT
1
3.1
The Planning Act 2008 defines the Proposed Development as a ‘nationally significant
infrastructure project’ (NSIP) as it is an onshore electrical generating station with more than
50MW capacity. Under Section 31 of the Planning Act 2008, a Development Consent
Order (DCO) Application is required for a NSIP.
3.2
Policies for NSIPs are set out in the National Policy Statements (NPS). Those that are
relevant to the Proposed Development and CHP assessment are described below.
Overarching National Policy Statement for Energy EN-1 (NPS EN-1)
3.3
Section 4.6 of the NPS EN-1 highlights considerations for CHP and describes the
government’s commitment to reducing carbon dioxide (CO2) emissions through the
promotion of good quality CHP and outlines the assessment criteria. In particular, it:
(1) Describes CHPs as “Combined Heat and Power (CHP), which is the generation of
usable heat and electricity in a single process. A CHP station may either supply steam
direct to customers or capture waste heat for low-pressure steam, hot water or space
heating purposes after it has been used to drive electricity generating turbines. The
heat can also be used to drive absorption chillers, thereby providing cooling.”
(2) Highlights that heat generated by CHPs can substantially reduce the amount of fuel
consumed that would otherwise be wasted. Although there are other methods for
thermal generation gas-fired is considered the most viable option.
(3) Denotes the benefits of CHP being a less CO2 intensive method of heating and
electricity generation. This is because the technology uses less fuel to produce the
same amount of heat and power than conventional methods. In order to be eligible for
the government support, associated with the CHP Quality Assurance programme, in
accordance with the EU Cogeneration Directive, schemes need to achieve at least 10%
primary energy savings.
(4) Emphases that according to Department for Environment, Food and Rural Affairs
(DEFRA), in 2009, there was a total of 5.6 gigawatts (GW) of ‘Good Quality’ CHP in the
UK, providing over 7% of electricity and saving an estimated 9.5 megatonnes of carbon
dioxide (MTCO2) per annum. DEFRA believes that, potentially, there is cost-effective
development for a further 10 GW of ‘Good Quality’ CHP, estimated to offer a further
saving of 175 MTCO2 by 2015.
(5) States that in order for CHP to be considered as economically viable the plant needs to
be closely located to consumers with heat demands, though this distance will vary with
the nature of the demand. An example of a cost-effective distance from a Department of
2
Energy and Climate Change (DECC) report on district heating networks is given as
200 megawatts thermal (MW th) of heat within 15 kilometres (km).
(6) Denotes that DCO Applications must either include CHP or contain evidence that the
possibilities have been fully explored.
(7) Refers to liaising with potential heat consumers if identified and also bodies such as the
Homes and Communities Agency (HCA), Local Enterprise Partnerships (LEPs) and
Local Authorities (LA).
1
2
http://services.parliament.uk/bills/2007-08/planning.html
The Potential and Costs of District Heating Networks, Pöyry and Faber Maunsell, April 2009
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(8) Explains that, where the proposal is for thermal generation without CHP, the applicant
should:
• Explain why CHP is not economically or practically feasible;
• Provide details of any potential future heat demands in the area; and
• Detail provisions in the proposed scheme for exploiting any potential heat
demand in the future.
(9) States that as some CHP systems require more plant room space than non-CHP
generating systems. Applicants must show and explain how current and / or planned
CHP systems will be integrated into the proposed site and be Carbon Capture ‘ready’.
National Policy Statement for Fossil Fuel Generation EN-2 (NPS EN-2)
3.4
CHP considerations and guidelines are described in Section 2.3 of NPS EN-2. These are
to be considered in conjunction with those outlined in NPS EN-1 and the guidance
document created by the Department of Trade and Industry (DTI) on Background
Information to Accompany Notifications Under Section 14(1) of the Energy Act 1976 and
Applications under Section 36 of the Electricity Act 1989 (December 2006).
3.5
Paragraph 2.2.4 of this NPS states that sufficient space must be allocated for CHP
systems and relates to EN-1 (Section 5.10)
3.6
Paragraphs 2.3.2 and 2.3.3 state that all CHP options need to be fully explored and
applicants must include considerations and show evidence in conjunction with EN-1
(Section 4.6). Where there is reason to believe that future opportunities for CHP may arise,
if a non-CHP solution is proposed, then developers are required to ensure that the station
is ‘CHP ready’ to allow heat supply at a later date. All applicants must demonstrate that
CHP has been considered and the IPC (now the Planning Inspectorate) should not give
development consent until it is satisfied sufficient evidence has been provided (EN-1
Section 4.6.8).
National Policy Statement for Electricity Networks Infrastructure (EN-5)
3.7
This NPS is to be used alongside EN-1 and forms the basis for assessment of the Planning
Inspectorate’s electricity networks infrastructure decisions. It does not specifically refer to
CHP.
Guidance on background information to accompany notifications under Section 14
(1) of the Energy Act (1976) and applications under Section 36 of the Electricity Act
3
(1989)
3.8
The DTI provides guidance for new power stations and electricity and heat generation.
3.9
Paragraph 11 provides details of the evidence and steps that need to be taken by the
applicant in order to assess the viability of CHP. These include:
• An explanation of their choice of location, including the potential viability of the site
for CHP;
• A report on the exploration carried out to identify and consider the economic
feasibility of local heat opportunities and how to maximise the benefits from CHP;
• The results of the exploration; and
• A list of the organisations contacted.
3
December 2006
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3.10
Paragraph 12 of the Guidance lists what must be included with applications where CHP is
not to be included. This includes:
• The basis for the developer’s conclusion that it is not economically feasible to
exploit existing regional heat markets;
• A description of potential future heat requirements in the area; and
• The provisions in the proposed scheme for exploiting any potential heat demand in
the future.
3.11
Paragraph 14 identifies some of the largest and likely most economically viable prospective
consumers to be considered. These are as follows:
• Industrial sectors;
• Commerce, including;
o Hotels
o Leisure centres
o Large public buildings
• Public services, including;
o Hospitals
o Universities
o Prisons
o Defence installations
3.12
Paragraph 16 provides the details of the elements that should be demonstrated and
included in applications:
• That the DECC UK heat map has been consulted;
• Information gathered from regional and local planning bodies to identify
opportunities;
• A number of different heat markets have been explored;
• Consulted DEFRA, Combined Heat and Power Quality Assessment (CHPQA)
programme administrator and Regional Development Agencies (RDAs were
abolished in 2012. Some of the roles of the RDAs are now undertaken by smaller
scale Local Enterprise Partnerships (LEPs)); and
• The following have been identified as possible sources for general information:
Combined Heat and Power Association (CHPA), The Energy Savings Trust and
the Carbon Trust.
3.13
Paragraph 19 stresses that where heat opportunities have been identified developers
should carry out detailed studies on the economic feasibility of these. Paragraphs 20 -22
provide further guidance on economic feasibility.
Environment Agency, CHP Ready Guidance for Combustion and Energy from Waste
Power Plants
3.14
The EA has recently published detailed guidance on CHP Readiness Assessments as part
of the Environmental Permitting regime. The EA requires application for Environmental
Permits to demonstrate Best Available Technology (BAT) for a number of criteria, including
energy efficiency. One of the principal ways of improving energy efficiency is through the
use of CHP. The EA therefore requires developers to satisfy three BAT tests in relation to
CHP. The first involves considering and identifying opportunities for the use of heat offsite. Where this is not technically or economically possible and there are no immediate
opportunities, the second test involves ensuring that the plant is built to be ‘CHP ready’.
The third test involves carrying out periodic reviews to see if the situation has changed and
there are opportunities for heat use off site.
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3.15
The EA guidance reiterates the need for applications for Development Consent involving
generating stations to be supported CHP Assessment in line with Section 4.6 of EN-1,
which contains details on:
•
•
•
•
•
An explanation of their choice of location, including the potential viability of the site
for CHP;
Identifying the CHP and carbon capture envelope for a CCR plant;
A report on the exploration carried out to identify and consider the economic
feasibility of local heat opportunities and how to maximise the benefits from CHP;
The results of that exploration; and
A list of organisations contacted.
3.16
In addition, if the proposal is for generation without CHP:
• The basis for the developer’s conclusion that it is not economically feasible to
exploit existing regional heat markets;
• A description of potential future heat requirements in the area; and
• The provisions in the proposed scheme for exploiting any potential heat demand in
the future”.
3.17
Where Development Consent is granted for a new plant without CHP, the subsequent
application for an Environmental Permit should build on the conclusions of the CHP
Assessment and contain sufficient information to demonstrate the new plant will be built
‘CHP ready’ (for the chosen location and design)
National Planning Policy Framework (NPPF)
3.18
The National Planning Policy Framework released in 2012 provides guidelines for Local
Planning Authority plans. The following provides details those relevant to CHP,
decentralised energy and district heating.
3.19
Section 10 of the NPPF describes how opportunities should be identified for developments
to supply heat from decentralised, renewable or low carbon energy sources.
3.20
Section 15.6 of the NPPF specifies that Local Plans should set strategic priorities to deliver
provisions for infrastructure, including energy and heat.
Defra, Transposition in England and Wales of Articles 14(5)-(8) of the energy
efficiency Directive (2012/27/EU) – Consultation
3.21
Defra is currently going through a consultation process on the transposition of Articles
14(5)-(8) of the EU’s Energy Efficiency Directive EED – (2012/27/EU) which was adopted
in October 2012.
3.22
The objective of Article 14 is to encourage the identification of cost-effective potential for
delivery energy efficiency, through the use of cogeneration, efficient district heating and
cooling and the recovery of industrial waste heat. New thermal electricity generation
installations with a total thermal input exceeding 20 MW are to assess the costs and
benefits of providing high-efficiency cogeneration installations.
3.23
Defra is conducting a consultation process in February and March 2014 which will inform
the requirements of that are to be included in the Cost Benefit Analysis (CBA). The
consultation document references Article 14(5) which states that Member States shall
ensure that relevant installations shall carry out a CBA after 5 June 2014.
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South Gloucestershire Council Local Development Framework
3.24
The SGC Core Strategy forms a key part of the portfolio of Local Development Framework
planning documents. The key policy in relation to heat recovery is as follows:
3.25
Policy CS4 – Renewable or low carbon district heat networks outlines how any applications
to develop a thermal generation station or proposals that have a capacity to generate
significant waste heat as part of an industrial or commercial process must either:
o Include heat recovery and re-use technology; and
o Heat distribution infrastructure; or
o Provide evidence that heat distribution has been fully explored and is
unfeasible
3.26
The South Gloucestershire Local Plan (Saved Policies) encourages the inclusion of
combined heat and power and district heating technology on a building scale but does not
include policies of relevance to industrial processes.
Bristol Local Development Framework
3.27
Bristol City Council’s (BCC) Core Strategy outlines the overall approach for planning
developments in Bristol. Policy BCS14 ‘Sustainable Energy’ describes BCC’s support for
the development of low-carbon sources of energy including CHP, Combined Cooling Heat
and Power (CCHP) and district heating, and outlines how new developments are to
demonstrate the suitability of these for their development, particularly in Heat Priority
Areas. The core strategy refers to the Bristol City-wide Sustainable Energy Study, where
Avonmouth is identified as having potential for CHP/CCHP plant, potentially for biomass,
but recognises that in the short term a connection to the City Centre heat loads are not
likely to be economically viable.
3.28
Policy BCS 15 ‘Sustainable Design and Construction’ aims to ensure new developments
minimise their environmental impact and meet targets for CO2 reduction. BCC objectives
are to integrate sustainable design and construction to all new developments and one key
issue is to maximise energy efficiency and integrate Low and Zero Carbon (LZC) energy.
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4
OBJECTIVES AND APPROACH
4.1
Based on the planning context described above the following scope was developed:
•
•
•
•
•
To identify and assess the magnitude of the industrial and other significant heat
demands which are within the vicinity of the Proposed Development; Identify future
potential loads;
To comment on the projected economic and technical feasibility of connection to
heat users identified above;
Where viable connections are identified provide a list of the relevant organisations
contacted;
To assess the good quality CHP implications of heat demand uptake scenarios
representing a range of heat network extents; and
Outline the provisions made for exploiting any potential heat demands in the future
including a CHP-R Assessment where immediate heat loads are not found to be
viable.
General Methodology
4.2
In order to address the items above the following methodology has been utilised.
4.3
The viability of a potential heat load is dependent on both the size of the heat load and the
distance it is located from the heat source. Therefore two search zones have been
identified. A 15km radius search zone has been used to identify very large heat loads and
a 5km radius has been used to identify smaller heat loads.
4.4
Initial heat load density and large heat load consumer searches for 15km and 5km search
areas have been conducted through consulting with the following resources:
•
•
4.5
The National Heat Map; and
CHP Database and District Heating (DH) installation map.
Using the information gathered from these sources, areas to focus on in greater detail have
been identified. Maps, satellite information and GIS data have then been used to estimate
individual heat loads for particular sector types in the areas identified using benchmark
heat demand data. The sector types focussed on in this study, as recommended by the
4
DTI guidance document , are as follows:
•
•
•
•
•
•
•
•
4
Industrial users;
Hotels;
Leisure centres;
Large public buildings;
Hospitals;
Universities;
Prisons; and
Defence installations
Guidance on background information to accompany notifications under Section
14(1) of the Energy Act 1976 and applications under Section 36 of the Electricity Act
1989
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4.6
Following the identification of existing core potential heat loads the potential of future
developments occurring in the area will be undertaken through gathering information from
the following bodies:
•
•
Planning application notifications; and
Information available from local authorities
4.7
Analysis of the available heat output from the plant, impact on electricity generation and
potential to export to consumers has been undertaken, followed by a Combined Heat and
Power Quality Assessment (CHPQA) calculation to understand if the heat and power
generated can be classified as ‘good quality’.
4.8
Following this analysis the key technical and commercial considerations are discussed and
provisions for exploiting potential heat demands in the future outlined. A CHP-R
Assessment Form is included in Annex C – CHP-R Assessment Form.
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5
Heat Density Analysis
The National Heat Map
5
5.1
The National Heat Map has been designed by The Centre for Sustainable Energy and
commissioned by DECC. This tool can be used to search for potential viable heat loads for
CHP and district heating applications in support of planning and deployment of local
sustainable projects in England.
5.2
The viability of a heat connection is dependent on the size of the heat load and its proximity
to the source of heat. As outlined in the EN-1 guidance and the scope presented in Section
3, a search area of 15km has been used to identify very large heat loads. A 5km search
area has then been assessed in order to identify smaller heat loads which may be viable
connections due to their closer proximity to the source of heat at the Proposed
Development. The River Avon, just over 5km to the south of the Proposed Development
Site, also provides a natural barrier to the installation of heating infrastructure connecting to
the Proposed Development beyond this range in this direction.
5.3
The 15km search radius heat map indicates that the largest heat loads in this search area
are located in Bristol City Centre, approximately 10km from the Proposed Development
Site. The National Heat Map shows some areas reaching a relatively high heat density of
over 200 kilowatt-hours per square metre (kWh/m2). The heat map however, also indicates
that there are very few existing developments with any heat loads between the Proposed
Development and Bristol City Centre, which may reduce the viability of connection to the
city centre, due to the scale of heat losses and capital costs of installation; unless a single
very large head demand is identified.
5.4
The 5km radius heat map indicates that within this closer proximity search area, Severn
View Industrial Park, Cabot Park and Patchway have the most significant heat load
densities. Though the heat density of these areas are comparatively lower at 100 kWh/m2,
due to their closer proximity to the Proposed Development Site they may provide more
viable options for developing a district heat network compared to a single large load at a
greater distance.
5
http://tools.decc.gov.uk/en/content/cms/heatmap/about_map/about_map.aspx
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Figure 1: National Heat Map - Heat Density in a 15 km Radius
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13
Seabank 3 Combined Heat and Power Assessment
Figure 2: National Heat Map - Heat Density in a 5 km Radius
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14
Seabank 3 Combined Heat and Power Assessment
UK CHP Development Map
6
5.5
The UK CHP Development Map has been created by DECC to support the development
of CHP systems in the UK. Initially produced to assist developments in the planning
process, the tool can be used to identify the size and location of existing CHP and District
Heating systems and also areas of high heat demand for the development of new systems.
2
Heat densities are expressed in peak demand format (kW/km ), as opposed to the annual
heat consumption (kWh/m2) as described by the National Heat Map.
5.6
Similar to the above, a search area of 15km has been used to identify very large heat
demands and a 5km search area has then been assessed in order to identify smaller heat
loads which may be viable connections due to their closer proximity to the source of heat.
5.7
The CHP development map identified total heat loads of around 2,550 MW within the 15km
radius and around 203 MW within the 5km radius. The Severn View Industrial Estate and
Severn Beach are identified as one of the areas with the highest net load density within the
5km search criteria.
5.8
By sector, the largest heat demand has been found to be from domestic consumers,
accounting for 60% of the heat demand in the 5km radius search area, rising to over 75%
in the 15km search area. Though this sector may represent the greatest heat demand, the
heat load density is considered too low to enable viable heat delivery from a district heating
system in the majority of cases. This is due to the large amount of heat distribution network
that would be required to enable the connections, which in turn corresponds to high heat
losses and capital cost of installation, notwithstanding the logistical and commercial
complexity of connecting numerous existing low rise residential properties.
5.9
Other sectors with high heat demands have been found to be: Small & Large Industrial
units (23%), Retail (3%), Commercial Offices (2%) and Hotels (1%). These sectors, in
addition to those suggested in the DTI guidance document, have been used to inform a
more detailed search for specific heat consumers in the next stage of analysis.
6
http://chp.decc.gov.uk/developmentmap/
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Figure 3: UK CHP Development Map - Heat Density in a 15 km Radius
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16
Seabank 3 Combined Heat and Power Assessment
Figure 4: UK CHP Development Map - Heat Density in a 5 km Radius
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17
Seabank 3 Combined Heat and Power Assessment
5.10
In addition to identifying the heat load density of the area, the UK CHP Development Map
provides information on specific large heat consumers, the proportion of their existing heat
requirements that are fulfilled by CHP technology, and if there are existing district heating
networks that the system could feed into. Table 1 provides details of the largest heat loads
identified in the area and Figure 5 shows their location in respect to the Proposed
Development.
Table 1: Major Heat Consumers in a 10km Radius
Map
Reference
Large Heat
User
Approx.
Distance
(km)
Total Heat
Load (kW)
Provided
by CHP
(kW)
Total
Remaining
Load
(kW)
A
AstraZeneca
UK Ltd
1
7,129
-
7,129
B
Bristol Energy
Limited
7
7,496
-
7,496
C
United Bristol
Heath Care
NHS Trust
10
6,539
4,116
2,423
D
University of
Bristol
10
8,717
1,716
7,001
Figure 5: UK CHP Development Map - Major Heat Consumers in a 15km Radius
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5.11
Of the large heat loads identified within the search area, the AstraZeneca site on the
Severn View Industrial Estate represents the greatest opportunity as a potential heat
consumer from a district heating network. It is within 1 km of the Proposed Development
Site and none of its 7 MW heat demand is currently supplied by CHP.
5.12
There is some existing infrastructure situated between the Proposed Development Site and
the existing AstraZeneca site, including various drainage channels such as the Red Rhine
and a railway line, which would cause some challenges for the installation of a district
heating network. The rail lines currently running to the south of the Severn View Industrial
Park appear at present to be unused, nevertheless, suitable agreements would need to be
put in place to install infrastructure in this area.
5.13
The other two significant heat loads identified in the centre of Bristol are of a similar scale,
in the order of 7 to 9MW, however a significant proportion of their heat loads are already
provided by CHP so the motivation for an additional CHP heat connection is not likely to be
high. These loads are not significant enough to consider a 10km installation of buried
network and have therefore not been considered further.
Future Developments
Generating Station Developments
5.14
In addition to the existing Seabank 1 & 2 station and the Proposed Development there are
plans for additional generating stations in close proximity to the Proposed Development
Site.
5.15
The following schemes have been granted or are known of within 1km of the Proposed
Development Site:
• There is the consented Severnside Energy Recovery Centre (SERC) which is
currently under construction by SITA, and expected to be operational by 2016. This
is located immediately west of the Proposed Development Site and is expected to
have the capability to process up to 400,000 tonnes of waste a year, with a
7
generating capacity of up to 32 MW e ;
• Scottish Power began a consultation process for a new 900-1,200 MW e CCGT
power station in 2011/12 on the former Terra Nitrogen ICI site, immediately north of
8
the Proposed Development Site . A meeting note is logged on the National
Infrastructure Planning portal dated September 2012, however no further
submissions are included;
• VIRIDOR has planning permission granted for a Resource Recovery Centre
including an energy from waste and bottom ash facility, approximately 500m south
of the Proposed Development. This is anticipated to have a capacity in the region
of 500,000 tonnes per annum of waste, with a generating capacity of up to 30
MW e;
• W4B is a bio-fuel energy plant on the Former Columbian Chemicals (Sevalco),
Severn Road, which was granted on appeal and is located approximately 700m
south of the Proposed Development. This is anticipated to have a capacity to
generate and combust in the order of 90,000 tonnes of oil per annum, with a
generating capacity of up to 50 MW e; and
• The New Earth Anaerobic Digestion Facility is located approximately 900m
southeast of the Proposed Development Site. This has a capacity in the order of
50,000 tonnes per annum of waste, with a generating capacity of up to 3 MW e.
7
8
http://www.sita.co.uk/news-and-views/our-plans/severnside
http://www.avonpowerstation.com/
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5.16
A further three biomass and energy recovery generating station plants have been granted
planning permission approximately 2.5km south of the Proposed Development Site.
5.17
These developments could have the potential to generate heat as part of a CHP process.
The Severnside Energy Recovery Centre, which is currently under construction, submitted
a Heat Plan as part of the planning submission in 2009 that includes many of the potential
consumers identified in this study. It is understood that it will not be providing heat to
surrounding developments, which indicates that no appropriate heat consumers have yet
been identified.
5.18
If a heat network were to become viable in this area it is likely that a number of other
developments in Servernside (including the Severnside Energy Recovery Centre) would
provide a more appropriate heat source in the first instance, due to its continuous
generation, compared to the Proposed Development which will be more intermittent. The
Energy Recovery Centre is likely to be a more consistent and predictable heat source for
consumers as it is expected to run as a base load plant rather than the intermittent
operation expected for the Proposed Development, reducing the need for top-up provision
from alternative sources, and so a more efficient system as a whole. This would however
reduce the available heat loads in the area, further reducing the potential for the Proposed
Development’s provision of CHP.
Bericote Avlon Development
5.19
Planning permission was granted in August 2011 for up to 120,000 square metres (m2) of
manufacturing and distribution developments. The site is located within 1km to the north of
9
the Proposed Development . This development may provide future heat loads for a district
heating system, however due to the industrial nature of this site it does not necessarily
guarantee that the units when developed will have heating requirements or if they do that
they would be of sufficient scale to make connections viable.
Central Park Western Approach Development
5.20
2
10
Central Park is a warehouse and distribution park development with 93,000m capacity
that is currently under construction to the northeast of the Proposed Development Site.
These units currently have planning permissions in place and are being offered as a design
and build packages. However, similar to the Bericote Avlon development, due to its
industrial nature it is not guaranteed that they will prove to have suitable heating loads to
enable a connection to a district heating system.
Cribbs/Patchway New Neighbourhood
5.21
There are plans currently in consultation on the development of an entirely new
neighbourhood in the Cribbs/Patchway area 3-6km to the east of the Proposed
Development. These would include an additional 5,700 dwellings, 6 new schools and
additional commercial, community and retail space to be constructed over a period of 1011
15 years . At the time of writing, initial framework plans had been submitted to the council
and the landowners were waiting on a response to the proposals.
5.22
This new development could provide a substantial opportunity for the development of a
district heating network in this area. However, the viability of this will depend on the density
of the heat loads. Though there are expected to be a large number of additional dwellings
developed, if these are single storey houses rather than communal high density units, such
9
http://www.bericoteproperties.com/land-portfolio/avlon-bristol/overview/
http://www.centralparkbristol.co.uk/the-scheme/ariel/
11
http://www.southglos.gov.uk/Documents/Cribbs%20Patchway%20Exhibition%20material.pdf
10
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as blocks of flats, the large amount of network required to connect each of them and
associated cost and heat losses would likely make large scale connections unviable.
GIS Mapping and Heat Benchmarking
5.23
Building on the information from above, GIS mapping and satellite information of the
search area has been used to conduct a more refined search to identify specific
consumers. This approach also enables clusters of heat loads to be identified in greater
detail. A number of consumers with a moderate heat demand may, when considered
together, provide opportunities for district heating network where individual developments
would not.
5.24
In accordance with the DTI guidance document, searches for heat loads such as industrial
consumers, hotels, leisure centres, large public buildings, hospitals, universities/teaching
institutions, prisons and defence installations have been undertaken. These categories
represent buildings that are likely to have significant heat loads and may have existing
centralised plant systems, which simplifies connection to a district heating network.
5.25
Sites with an area greater than 2,000m were used as an initial measure for buildings
which may have relatively large heat consumptions. A full list of the buildings found in
these categories is included in Annex B.
5.26
Following this initial identification process a heat benchmarking exercise was undertaken to
understand the size of the heat demands. The approximate area of the buildings was
calculated based on URS’s in house GIS tool. CIBSE Guide F and CIBSE TM46 typical
practice benchmarks were used to identify the approximate heat demands.
5.27
Table 2 details the benchmarks assumed.
2
Table 2: Heat Benchmarks
Type of building
Schools – Primary/ Secondary
Fossil Fuel
Thermal
Benchmark
2
(MWh/m p.a)
0.15
Retail / Warehouse
0.17
Major retail/ Department stores
0.19
Leisure Pool Centre
1.13
Combined centre
0.59
Industrial/Distribution Warehouse
0.023
Chemical factory
0.595
5.28
The heat users within the region of interest were categorised into three groups based on
their annual estimated heat consumption, in order to identify those with the greatest
potential and eliminate those with the lowest. Table 3 illustrates these three bands of heat
demand and their limiting values.
5.29
Industrial buildings and warehouses tend to vary considerably in their heat usage
depending on the nature of their operations. Therefore for such buildings a number of
benchmarks have been consulted in order to determine the most appropriate. These have
ranged from zero heat consumption up to 0.18 MWh/m2. In order to provide a conservative
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view on the initial heat benchmarking assessment 25% of the good practice CIBSE F
industrial benchmark has been utilised. The next recommended stage to determine the
viability of connection, following this initial assessment, would be to gather metered data
from the identified potential consumers to develop detailed heat profiles.
Table 3: Heat Load Categories
Category
High potential
Heat consumption
(MWh p.a)
above 5000
Medium potential
1000-5000
Low potential
below 1000
5.30
This process removed all of the schools as potential opportunities and many of the smaller
distribution/warehouse units. The remaining heat loads were then further refined to take
into account their proximity to the Proposed Development and if there were any particular
areas of clusters which could provide opportunities for the development of district heating
networks. The results of this are shown in Figure 6 and Table 4.
5.31
From this initial analysis the development with the greatest potential was found to be the
Astra Zeneca site due to its close proximity to the Proposed Development and its relatively
high peak heat requirement of 7MW and an estimated annual heat consumption of 11,000
MWh per annum.
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Figure 6: Identified Heat Loads in a 5km Radius
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23
Seabank 3 Combined Heat and Power Assessment
Table 4: Identified Heat Loads in a 5km Radius
Map
Reference
Building
A
Astra Zeneca
B
Western Approach
Distribution
C
Chittening Industrial Estate
D
Severnside trading estate
E
St Martins Industrial Park
F
G
H
St Brendan's Industrial
Estate
Cabot Park Industrial
Estate
Crowley way Industrial
Estate
I
St andrews trading estate
J
Cribs Causeway Centre
industrial estate
K
Distribution Centre
L
The Venue Retail Park
M
N
O
Patchway trading estate
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April 2014
Type of Use
Industrial/trading
estate
Industrial/trading
estate
Industrial/trading
estate
Industrial/trading
estate
Industrial/trading
estate
Industrial/trading
estate
Industrial/trading
estate
Industrial/trading
estate
Industrial/trading
estate
Industrial/trading
estate
Industrial/trading
estate
Estimated.
Heat load
(MWhp.a)
Heat User
Category
Proximity to
Site
Proximity to a
Cluster
Overall
Potential
High
High
High
High
3,846
Medium
High
High
High
1,076
Medium
High
Medium
Medium
1,895
Medium
Medium
Low
Low
Low
High
Low
Medium
1,279
Medium
Low
High
Medium
1,904
Medium
Medium
Medium
Medium
Low
Low
High
Medium
Medium
Low
High
Medium
234
Low
Low
Medium
Low
902
Low
Low
Medium
Low
Medium
Low
Medium
Medium
11,353
315
865
1,704
Retail Park
1,360
Cribbs Mall Retail Park
Retail Park
14,280
Asda
Retail Park
Industrial/trading
estate
High
Low
High
Medium
2,176
Medium
Low
High
Medium
1,205
Medium
Low
Medium
Medium
24
Seabank 3 Combined Heat and Power Assessment
6
CHP ANALYSIS
6.1
The development comprises of up to 1,400 MWe of generating capacity based on a
combination of: one or two natural-gas-fired CCGT with a generating capacity of up to 700
MWe each and peaking plant units with a generating capacity of up to 240 MWe.
6.2
The peaking plant(s) will be designed to ‘black start’ on distillate in the event of failure of
the national grid, to help restart the grid. The peaking plant will also provide fast response
‘top up’ supply to the grid during peak periods.
6.3
Electricity will be generated by the gas turbines by mixing combusted gas and compressed
air which, as the pressure is reduced, expands and rotates the turbine blades, which then
drives a generator. After the hot gases pass through the turbine they are then channelled
through a Heat Recovery Steam Generator (HRSG) boiler to provide high pressure steam
to a steam turbine which in turn drives a generator providing additional electricity. The use
of a steam turbine in addition to the gas turbine provides the combined cycle rather than
single. The waste gases are then exhausted to the atmosphere form the HRSG boiler. The
steam turbine is cooled and its output optimised by using a condenser, which circulates the
water to hybrid cooling towers.
6.4
The most viable option for heat extraction is from the steam turbine, which has the most
compatible temperatures for district heating applications and the least impact on power
generation. However, the higher the pressure of steam extracted from the turbine, the
greater the corresponding loss of electrical efficiency. It is therefore recommended to
extract the heat at the lowest compatible pressure required by the consumers. For District
Heating applications providing hot water for space heating and DHW generation in
particular this may be Low Pressure (LP) steam, or where possible Medium or Low
Temperature Hot Water.
6.5
The Proposed Development has been designed to operate for at least 7,700 hours per
annum on average, equivalent to an overall average availability of 85-90%. The actual
running hours of the turbines will be subject to demand. It is however, as detailed in the
Project Description report, anticipated that the CCGTs will actually operate at 31% load
over the course of its lifetime (an average of 2,716 hours per year).
6.6
The peaking plant will be limited to a maximum 1,500 hours a year, which is approximately
17% load. This is a maximum, and in reality the operation will be intermittent, infrequent
and cannot be guaranteed. For this reason the option of CHP from the peaking plant has
been discarded and is not considered further in this assessment.
6.7
A CCGT plant such as the Proposed Development operated as a CHP system can be
entitled to fiscal and other incentives such as Climate Change Levy (CCL) exemption and
Enhanced Capital Allowances (ECA) where applicable, if it qualifies under the good quality
CHP programme.
6.8
This following section investigates the potential quality of CHP for any hypothetical heat
network. In assessing qualification as a Good Quality CHP (GQCHP) system, there are a
number of key criteria involved. In order for the power outputs under annual operation to be
fully eligible for CCL exemption and ECAs, the ‘quality index’ of its performance must be
greater than 105 for new plants with a Power Efficiency of greater than 20% under annual
12
operation . The guidance note GN-10, available from “quality assurance for CHP
schemes” provides the calculation methodology for the Quality Index (QI). The formula
12
http://chpqa.decc.gov.uk/guidance-notes/
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below is abstracted from GN-10, Table GN10-2, and is applicable for the calculation of QI
for natural gas fired new plants.
Fuel:
Formula:
Natural gas
QI = (172 x ηpower) + (115 x ηheat)
(where the installed capacity range is greater than 500 MW e)
ηpower = Electrical efficiency
ηheat = Thermal efficiency (based on useful heat supplied)
6.9
The amount of power and heat generated by the plant will depend on its mode of
operation. At this stage of development, full thermal modelling has not been undertaken on
the CCGT units to understand the impact on efficiencies if heat is extracted from the CCGT
system. Notional efficiencies have therefore been derived from similar systems to give an
indication of the performance of the system and the scale of heat extraction required to
meet minimum CHPQA requirements.
6.10
Table 5 summarises the indicative CHPQA performance of three notional operational
modes at full output, based on a CCGT generating station up to 1,400MWe. This assumes
the system operates at these outputs all year round with all heat extracted used usefully for
heat supply to consumers, and with no other heat source, or fuel source, providing top-up
heat to the system. Without detailed thermal modelling these are outline estimates only at
this stage and will vary depending on actual annual operation.
Table 5: Notional CHPQA Calculation
Scenario
Fuel In MW
Heat
Extracted
MW th
Zero Heat Extract
MTHW Extract
Steam Extract
2414
2414
2414
0
141
195
Gross
Thermal
Electrical
Total
Electrical
Efficiency % Efficiency % Efficiency %
Output MW e
1400
1379
1343
0%
6%
8%
58%
57%
56%
58%
63%
64%
CHPQA
100
105
105
6.11
Table 5 indicates that MTHW extraction could be expected to provide greater efficiencies
than steam extraction and that a relatively small proportion of heat compared to electrical
generation would need to be extracted to meet the minimum good quality CHP criteria, with
a relatively low impact on the electrical efficiencies. However, though a small proportion of
the peak electrical generation, 140-200 MWth in terms of heat supply represents a very
substantial heat load. For example one of the largest heat loads found in the vicinity, Astra
Zeneca, has a peak heat demand of only 7 MW. Finding sufficient numbers of heat
consumers for this scale of heat generation to achieve the good quality CHP criteria is
therefore not at this time likely to be achievable.
6.12
In line with the CHP-R guidance, published by the EA, a CHP-R Assessment Form has
been completed in order to identify the CHP operating envelope and quantify its potential
performance see Annex C – CHP-R Assessment Form.
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7
TECHNICAL AND COMMERCIAL CONSIDERATIONS
7.1
This section provides technical and commercial considerations for the potential
development of a CHP based heat network based around the Proposed Development.
These are not exhaustive but do outline some key high-level considerations.
District Heating Network Considerations
7.2
Network Route - The route and sizing of the network need to be carefully considered so
that suitable provision for current and future connections are allowed for whilst minimising
the length of pipe network installed in order to reduce installation costs and heat losses.
7.3
Outside of the site the pipework would need to be routed along highways, and in order to
do so the Applicant would need to comply with the requirements of the New Roads and
Street Works Act 1991 (NRSWA) and other relevant design guides for Highways
installations of buried pipework. Traffic management would be required and limitations to
working hours identified. Where works may be required to route network through private
land negotiations and legal agreements concerning for wayleaves and easements would
be required with the land owner, which would influence the installation costs and
timeframes.
7.4
The level of existing sub-surface utilities will influence the potential routing of the district
heating pipework. Congested areas may provide a potential constraint/limitation on the
district heating network routing which could influence the viability of a network if long
lengths are required to route round certain areas or if the pipework needs to be buried to
such a depth that it becomes impractical to install.
7.5
Physical Constraints - In terms of physical constraints for installing a district heating
network the most significant obstacle in close proximity are the various drainage channels
including the Red Rhine and the railway line situated between the Proposed Development
Site and the existing AstraZeneca site which may cause some challenges for the
installation of district heating network. In the event that a suitable district heating load were
to become viable beyond the Red Rhine, appropriate infrastructure would need to be
installed to facilitate the expansion of a network and this may reduce the viability of
connecting these particular heat loads. The rail lines currently running to the south of the
Severn View Industrial Park appear at present to be unused, however suitable agreements
would need to be put in place to install infrastructure in this area.
7.6
At a greater distance of 2km and 4km respectively the M49 and M5 motorways may
influence the viability of expansion of a network to the east of the Proposed Development if
the Cribbs/Patchway connections prove to be viable, due to the complexity and additional
cost associated with these crossings. The River Avon to the south of the Proposed
Development Site provides a natural barrier to the expansion of a network beyond this
point; however this is just outside of the core 5km radius under consideration so is not
anticipated to have a significant influence.
Heat Supply Considerations
7.7
Grade of Heat Supply - The form of heat that is exported by the Proposed Development to
a district heating network, whether this is steam, MTHW or LTHW, is an important
consideration for maximising efficiencies and compatibility with the existing network. A
steam off-take reduces the overall efficiency of the turbine to a greater extent than a
MTHW off-take would. Heat losses from steam networks are higher than MTHW and the
majority of potential consumers identified are likely to require MTHW or LTHW rather than
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Seabank 3 Combined Heat and Power Assessment
steam. However, a steam system could provide greater flexibility of heat supply depending
on the grade of heat required in the area.
7.8
Where no suitable heat loads can be connected to at the time of construction the system
should be created to be CHP ready (CHPR) so that it is able to provide heat as and when it
becomes viable. Such provision can be made at the design stage, for instance identifying
points for steam or MTHW take-off and allowing sufficient space around these points for
access for fitting appropriate equipment for extraction such as heat exchangers, pipework
and associated control and metering systems, in addition to other additional heat extraction
equipment.
7.9
System Resilience - District heating systems can either provide all of the heating
demands of the consumer, including peaking and resilience requirements, or just a
proportion. If the entire heat demands are provided this system is dependent on sufficient
resilience being delivered from the central heat generating source, typically in the form of
top-up and back-up boilers in addition to the heat off-take from the turbine. This is generally
a more attractive solution to potential consumers, providing greater space and cost savings
from operating only one system, but this does require additional plant to be provided by the
district heating supplier to maintain resilience to the system as a whole. In general this
system tends to provide a more efficient district heating system that can benefit from
greater economies of scale and simpler control by centralising all of the heat generating
plant. If all the heat demands of the consumer are not provided by a connection to a district
network they would need to maintain their own top-up and back-up facilities to meet peak
demands, with the Proposed Development providing base load only.
7.10
Absorption Cooling - Heat could also be supplied via the district heating network to
enable cooling to be generated by absorption chillers on the consumer’s site. This would
provide an additional heat load for the system, which could optimise the use of heat
particularly during summer, usually the lowest seasonal point of utilisation, when there are
only typically Domestic Hot Water (DHW) demands. A key consideration for this heat
supply would be the need to install absorption chillers, and associated heat rejection
equipment, on the consumer’s site, with the associated costs and space provisions. This
has not been considered in detail at this stage of the project.
7.11
Contamination Issues - The heat supplied by the system is likely to be provided by a
MTHW or steam off-take from the turbine. If a steam system is selected this will be in the
form of a flow pipe providing steam and a return pipe with condensate. To ensure that the
condensate is clean and does not contain any contaminates, which would negatively
impact the operation of the turbine, considerations around suitable detection and/or
filtration would need to be made at the design stage.
Retrofit of Existing Buildings
7.12
Plant Lifecycle - Where existing developments have heat generating plant (e.g. a boiler
system) that has remaining life, motivation to connect to the system from the outset may
not be high due to capital cost of connection to the consumer. This could reduce the
number of viable consumers at least in the short term.
7.13
System Design - Compatibility of consumer secondary side systems (i.e. the heating
system components beyond the central generating boiler plant) to a district heating system
may influence the viability of a connection. There will be a cost of bringing district heating
pipe to the building. There will be a further cost to ensure that the customer is able to
successfully utilise the heat provided. This secondary side element will require detailed site
investigation and may result in the connection becoming unviable.
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7.14
Compatibility of Systems - Pressure and temperature compatibilities are important
considerations. Generally if the operating pressures and temperatures of the network are
higher than that required by the consumer then a heat exchanger can relatively simply
provide a hydraulic break and temperature reduction to the appropriate range. If the
temperatures of the network are lower than that required by the consumer, the heat may
not be useable or may only provide a partial solution to the consumer as pre-heat, which
would then require the consumer to maintain their own plant in addition to the district
heating supply.
Considerations for Connection to New Build Developments
7.15
System Design - Connections to new developments will typically provide a simpler district
heating connection in technical terms compared to retrofit. This is due to the greater ability
to influence the design of the consumer side systems to optimise the connection to the
particular district heating system, which a retrofit scenario will not typically offer to the same
extent.
Commercial Considerations
7.16
Heat Price and Connection Charge - Suitable mechanisms for an appropriate heat price
and potential connection charge for consumers would need to be established which
provide the consumer with an equivalent or better than whole life cost against appropriate
alternative systems, while providing sufficient revenues to enable a viable district heating
system to be operated.
7.17
Heat Supply Agreements - The length of heat supply agreement that a consumer can
enter in to is to be considered. District heating system heat supply agreements are often
long term in nature in order to ensure a revenue stream against the investment made in
constructing the network and installing the CHP plant. Commercial properties may be on
short-term leases that could deter potential consumers from connecting to the district
heating network. To an extent this can be contended with by ensuring that the heat supply
agreement is of a similar length of time to the life of the alternative plant system.
7.18
Number of Consumers - In order to ensure that the district heating system is viable it is
necessary to establish sufficient numbers of commitments from consumers to connect,
particularly at the early stages of a project. This can frequently be difficult to achieve, given
resistance to change and generally a conservative approach of organisations to
technologies that might appear to have a high level of risk.
CHP ASSESSMENT
April 2014
Seabank 3 Combined Heat and Power Assessment
8
CONCLUSIONS
8.1
This study has identified, via a variety of sources, the most promising heat demand users
in the vicinity of the Proposed Development. The estimates of heat demand have been
based on floor areas, estimated from GIS data and satellite information, and benchmark
energy consumption figures derived from recognised publications. This methodology has
limitations, as actual energy use for a given site has the potential to deviate considerably
from the norm that is represented by benchmarks. Nevertheless, given the combination of
sources for identifying significant heat loads in the area, this study provides reasonable
confidence that there is no single very significant users (e.g. >20MWth) of heat within the
primary 5km radius of the study, and that the local heat loads available vary considerably in
magnitude, heat profile and proximity from the Proposed Development Site.
8.2
The two areas of greatest potential for connection to a district heating system have been
identified as the Astra Zeneca site and the Western Approach Distribution Centre. Both
these developments are in reasonably close proximity to the Proposed Development and
from the information available at this stage may represent reasonable heat loads to enable
effective supply from a DH system. However, both of these sites, as with the majority of
potential heat consumers identified, are industrial in nature and therefore likely to have
bespoke requirements for heat, which may reduce their potential.
8.3
With the exception of the these two areas, there are predominantly only light industrial
facilities (existing or being consented) in reasonable proximity to the Proposed
Development Site, which are not considered individually or collectively to offer great
viability to become customers of a successful DH network at this time. This is a combined
function of both their relatively diffuse locations, low anticipated heat demands, and the
costs associated with DH connection, commercial agreements and administration.
8.4
There are currently a number of smaller scale energy facilities identified within 1km of the
Proposed Development Site. It is understood that none of these facilities will be providing
heat to surrounding developments, indicating that no appropriate heat consumers have yet
been identified by these developers. These facilities are generally of a smaller scale
compared to the Proposed Development (circa 20 to 30 MWe each) and if developed are
likely to be operating continuously, which is likely to be more compatible with the scale and
nature of heat demands that have been identified in the area. If a heat network were to
become viable it is likely that these other facilities would be better placed to provide a more
appropriate heat source in the first instance, due to their continuous generation compared
to the Proposed Development which will be generating significantly more intermittently.
These other facilities would therefore more likely to be able to provide a more consistent
and predictable heat source for consumers, reducing the need for top-up provision from
alternative sources, and so establishing a more efficient system as a whole. This would
reduce the available heat loads in the area, further reducing the potential for the Proposed
Development’s provision of CHP.
8.5
In conclusion, although the plant could provide significant volumes of heat when operating,
given the anticipated intermittent operating regime for the proposed development, it is not
considered that a CHP solution would be viable without significant additional back-up heat
production. Additionally, heat mapping studies that have been carried out indicates there is
no significant density of heat demand currently available in reasonable proximity to justify
the development of a heat network. For those heat loads that have been identified, or may
become available in the future, it is considered likely that these would be more effectively
supplied by the smaller scale energy facilities already proposed, consented and/or under
development within 1km of the Proposed Development Site
CHP ASSESSMENT
April 2014
Seabank 3 Combined Heat and Power Assessment
8.6
Despite these initial findings, the Applicant will ensure that the Proposed Development is
designed to be ‘CHP Ready’ and will carry out an on-going review of CHP potential,
including:
•
•
•
•
8.7
Maintaining a dialogue with heat users already approached;
Setting up a working group involving all key stakeholders to maintain momentum;
Carrying out an annual reviews to determine if there have been sufficient changes
in circumstances to warrant a new technical and financial review; and
Re-visiting the technical and economic assessments at least every 5 years or when
a change in circumstances warrants.
The above will be been incorporated into a Requirement contained within the draft
Development Consent Order.
CHP ASSESSMENT
April 2014
Seabank 3 Combined Heat and Power Assessment
ANNEX A – SITE LOCATION
CHP ASSESSMENT
April 2014
32
Seabank 3 Combined Heat and Power Assessment
ANNEX B – IDENTIFIED HEAT LOADS
Table 6: Identified schools in the 5km search area
Approx.
Distance
(km)
Postcode
Name of School
Approx.
Distance
(km)
Postcode
Severn Beach
Primary School
2
BS35 4PP
Woodstock
School
4
BS10 7AH
Harris School of
Motoring
3
BS35 4NH
Henbury Court
Primary School
4
BS10 7QH
Pilning School(SEbound)
3
BS35 4JG
Avonmonth
C.E.V.C. Primary
School
5
BS11 9LG
Saint Peter’s
Church of England
vc Primary School
3
BS13 8EF
Avon Primary
School
5
BS11 9NG
NAS Anderson
School
4
BS35 4JN
Wesley College
5
BS10 7QD
Bank Leaze
Primary and
Nursery School
4
BS11 0SN
Long Cross
Primary Nursery
5
BS11 0PA
Saint Bede’s
Catholic College
4
BS11 0SU
Weston Park
Primary School
5
BS11 0LP
City of Bristol
College
4
BS32 4QD
Kingsweston
School
5
BS11 0UT
Bristol Gateway
School
4
BS2 9UR
Blaise Primary
School
5
BS10 7EJ
Henbury School
4
BS10 7QH
Red Bus Nursery
& Pre-school
5
BS9 2PR
Name of School
Table 7: Identified supermarkets in the 5km search area
Approx.
Distance
(km)
Postcode
Supermarket
Approx.
Distance
(km)
Postcode
Tesco Kitchen
1
BS10 7SD
The Mall at Cribbs
Causeway
4
BS34 5DG
Booker Avonmouth
4
BS11 9YB
Mower
Supermarket
5
BS11 9DE
Supermarket
CHP ASSESSMENT
April 2014
Seabank 3 Combined Heat and Power Assessment
Approx.
Distance
(km)
Postcode
Aldi
4
BS10 7EL
Bristol Cribbs
Homeplus
5
Morrisons
Tesco Homeplus
Supermarket
Approx.
Distance
(km)
Postcode
GymRatz
5
BS11 9EG
BS34 5TS
Bobbetts
5
BS11 0DW
5
BS10 7UD
Asda Supercentre
5
BS34 5TL
5
BS34 5TS
Supermarket
Table 8: Identified retailers and leisure centres in the 5km search area
Approx.
Distance
(km)
Postcode
Retailer &
Leisure Centres
Approx.
Distance
(km)
Postcode
Colton Wood
Products
1
BS11 0YB
Currys PC World
4
BS34 5DG
Gloster Furniture
Ltd
2
BS35 4GG
Harveys Furniture
4
BS34 5UL
Bristol Street
Commercials
2
BS11 0YW
Sports Direct
4
BS34 5UR
Seven Beach
Antiques
3
BS35 4PE
Costco
5
BS11 9EZ
Henbury Leisure
Centre
4
BS10 7NG
Country Baskets
5
BS11 9DJ
HorwoodHomewa
res Ltd
4
BS11 9HX
Proton Cars (UK)
Ltd
5
BS11 9YR
B&Q Cribbs
Causeway
4
BS10 7TX
Admiral Harding
Ltd
5
BS11 9DJ
TK Maxx
4
BS34 5TS
Wincanton Group
5
BS11 9HA
Hobbycraft Bristol
4
BS34 5TS
Approx.
Distance
(km)
Postcode
Retailer &
Leisure Centres
Table 9: Identified hotels in the 5km search area
Approx.
Distance
(km)
Postcode
Name of the
Hotel
Berwick Lodge
3
BS10 7TD
The Royal Hotel
5
BS11 9AD
Premier Inn
Bristol Cribbs
Causeway
4
BS10 7TQ
Bradford Hotel
5
BS11 9LW
Name of the
Hotel
CHP ASSESSMENT
April 2014
Seabank 3 Combined Heat and Power Assessment
Name of the
Hotel
Approx.
Distance
(km)
Postcode
Approx.
Distance
(km)
Postcode
Travelodge Hotel
4
BS10 7TL
Cedar Lodge
5
BS10 6JU
Best Western
Henbury Lodge
Hotel
4
BS10 7QQ
Midland Lodge
5
BS11 9AD
Kingsmead Lodge
5
BS11 9NJ
The Miles Arms
Hotel
5
BS11 9LW
Shirehampton
Lodge Hotel
5
BS11 0DJ
Approx.
Distance
(km)
Post code
5
BS10 6AF
Name of the
Hotel
Table 10: Identified hospitals in the 5km search area
Name of Medical
Facility
Approx.
Distance
(km)
Post code
Name of Medical
Facility
St Peters Hospice
Brentry
5
BS10 6NL
Greenway
Community
Practice
Humphry Repton
House
5
BS10 6NA
Table 11: Identified industrial and trading estates in the 5km search area
Approx.
Distance
(km)
Postcode
Astra Zeneca
1
BS10 7ZE
Western
Approach
Distribution. 10
units
2
Chittening
Industrial Estate.
7 units
Severnside
trading estate. 7
units
Industrial/
Trading Estates
CHP ASSESSMENT
April 2014
Approx.
Distance
(km)
Postcode
St Brendan's
Industrial Estate.
17 units
4
BS11 9EZ
BS35 4GG
Distribution
Centre. 3 units
4
BS10 7TL
2
BS11 0YB
St andrews
trading estate. 19
units.
4
BS11 9YE
3
BS11 9AG
Cribs Causeway
Centre industrial
estate. 4 units
4
BS10 7TL
Industrial/
Trading Estates
Seabank 3 Combined Heat and Power Assessment
Approx.
Distance
(km)
Postcode
St Martins
Industrial Park. 4
units
2
BS11 0RS
Cabot Park
Industrial Estate.
8 units
3
BS11 0YW
Industrial/
Trading Estates
CHP ASSESSMENT
April 2014
Approx.
Distance
(km)
Postcode
Crowley way
Industrial Estate.
4 units.
5
BS11 9EZ
Patchway trading
estate. 12 units
5
BS34 5TA
Industrial/
Trading Estates
Seabank 3 Combined Heat and Power Assessment
ANNEX C – CHP-R ASSESSMENT FORM
#
Description
Units
Notes/Instructions
Requirement 1: Plant, Plant Location and Potential Heat loads
1.1
Plant Name
Seabank 3
1.2
Plant Description
Natural gas fired CCGT and peaking plant
with a total generating capacity of up to 1400
MWe.
1.3
Plant Location
(Postcode/GridRef)
1.4
Factors Influencing Selection
of Plant Location
1.5
Operation of Plant
Approximate postcode BS10 7SP. See Annex
A - Site Location.
• Potential CHP opportunities: The site is
within 10 km of Bristol city centre, 5 km of
Avonmouth and a in the order of 2 km of
the communities Severn Beach, Hallen,
Pilning and Easter Compton.
• Sufficient land available: Sufficient land has
been identified, see plant layouts below.
• Current land use: Grassland criss-crossed
with ditches that flow into the Severn
Estuary
• Compatibility with relevant Local Plans:
Bristol Local Development Framework has
identified Avonmouth as having potential
for CHP/CCHP plant, but also recognises
that in the short term a connection to the
City Centre is not likely to be viable.
• Environmental considerations: These are
discussed in detail in the EIA chapters.
• Proximity to suitable utilities and grid export
connections: Existing power station
developments have provided appropriate
provisions in proximity to the site.
• Suitability for CCS: CCS is applicable to the
site. Suitable provisions have been allowed
for.
a)
Proposed Operation Plant
Load
%
b)
Thermal Input at Proposed
Operational Plant Load
MW
c)
Net Electrical Output at
Proposed Operational Plant
Load
MW
CHP ASSESSMENT
April 2014
The Proposed Development has been sized
for an overall average availability of 85-90%
per annum. Actual run hours are subject to
demand and are anticipated to likely be in the
region of 31%.
2310 MWth for CCGT and 674 MWth for
peaking @ 100% load
Up to 1,400 MWe
Seabank 3 Combined Heat and Power Assessment
d)
e)
f)
g)
h)
i)
Net Electrical Efficiency at
Proposed Operational Plant
Load
Maximum Plant Load
Thermal Input at Maximum
Plant Load
Net Electrical Output at
Maximum Plant Load
Net Electrical Efficiency at
Maximum Plant Load
Thermal Input at Minimum
Stable Plant Load
j)
Net Electrical Efficiency at
Minimum Stable Plant Load
1.6
Identified Potential Heat
Loads
1.7
a)
b)
1.8
a)
b)
c)
Selected Heat Load(s)
Category (e.g.
Industrial/District Heating)
Maximum Heat Load
Extraction Requirement
%
%
MW
CCGT: 58.09% / peaking: 37.36%. The total
efficiency will be between these two points.
100
2310 MWth for CCGT and 674 MWth for
peaking @ 100% load
MW
Up to 1,400 MW
%
Anticipated to be in the range of 60%
MW
%
1662 MWth for CCGT and 445 MWth for
peaking @ 60% load
CCGT: 53.06% / peaking: 33.86% / The total
efficiency will be between these two points
@ 60% minimum load assumed
As detailed above no immediate suitable heat
loads have not been found.
A mixture of industrial, commercial and
residential heat uses have been considered.
MW
N/A
Export and Return Requirements of Heat Load
Description of Heat Load
Low pressure steam
Extraction
Description of Heat Load
Variable
Profile
District heating applications for space heating
and/or DHW generation in the region of 6. For
Export Pressure
bar a
industrial process use this would be specific
to future connection requirements.
d)
Export Temperature
0
e)
Export Flow
t/h
C
f)
Return Pressure
bar a
g)
Return Temperature
0
h)
Return Flow
t/h
CHP ASSESSMENT
April 2014
C
District heating applications for space heating
and/or DHW generation in the region of 80-95
0
C. For industrial process use this would be
specific to future connection requirements.
N/A
District heating applications for space heating
and/or DHW generation in the region of 3. For
industrial process use this would be specific
to future connections requirements.
For district heating applications for space
heating and/or DHW generation in the region
0
of 50-60 C. For industrial process use this
would be specific to future connection
requirements.
N/A
Seabank 3 Combined Heat and Power Assessment
Requirement 2: Identification of CHP Envelop
2
2.1
a)
b)
c)
d)
e)
f)
2.2
a)
b)
c)
d)
e)
f)
Comparative Efficiency of a
Standalone Boiler for
supplying the Heat Load
90 %
LHV
90
Heat Extraction at 100% Plant Load.
For the calculations below the following inputs for the extraction have been taken into
account: P=4bar, m=55kg/s (aprox. 20% of steam mass flow). The extraction comes
directly from a ST extract port so the temperature is fixed at 270 degC with an enthalpy
of 3008 kJ/kg. The steam is not desuperheated. Delivery pressure approx. 3 bar.
These are total values for both STs.
Maximum Heat Load
MW
165 MWth
Extraction at 100% Plant Load
Maximum Heat Extraction
Export Flow at 100% Plant
Load
CHP Mode Net Electrical
Output at 100% Plant Load
CHP Mode Net Electrical
Efficiency at 100% Plant Load
CHP Mode Net CHP
Efficiency at 100% Plant Load
Reduction in Primary Energy
Usage for CHP Mode at 100%
Plant Load
t/h
198 t/h (55 kg/s)
MW
Peaking output remains unchangeable,
CCGT: 1178 MWe
%
CCGT: 56.63%
%
CCGT: 63.67%
%
CHP-R guidance 2013 has been used.
CHPHȘ=63.67%,
CHPEȘ=56.63%,
RefHȘ=89%,
RefEȘ=58.09%.
The outcome gives 40.48%
Heat Extraction at Minimum Stable Plant Load. 60%.
At the load below the extraction pressure drops to 2.42 bar and the temperature at 263
degC. The enthalpy of the fluid goes down to 2993 kJ/kg
Maximum Heat Load
Extraction at Minimum Stable
MW
164 MWth
Plant Load
Heat Extraction Export Flow at
t/h
198 t/h (55 kg/s)
Minimum Stable Plant Load
CHP Mode Net Electrical
Output at Minimum Stable
Plant Load
CHP Mode Net Electrical
Efficiency at Minimum Stable
Plant Load
CHP Mode Net CHP
Efficiency at Minimum Stable
Plant Load
Reduction in Primary Energy
Usage for CHP Mode at
Minimum Stable Plant Load
CHP ASSESSMENT
April 2014
MW
Peaking output remains unchangeable,
CCGT: 763 MWe
%
CCGT: 51.04%
%
CCGT: 60.77%
%
CHP-R guidance 2013 has been used.
CHPHȘ=60.77%
CHPEȘ=51.04%
RefHȘ=89%
Seabank 3 Combined Heat and Power Assessment
RefEȘ=58.09%.
The outcome gives 35.96%
2.3
Can the Plant supply the
Selected Identified Potential
Heat Load (i.e is the Identified
Potential Heat Load within the
'CHP Envelope')?
Yes
Requirement 3: Operation of the Plant with the Selected Identified Heat Load
3.1
a)
Proposed Operation of Plant with CHP
CHP Mode Net Electrical
Output at Proposed
MW
Operational Plant Load
N/A
b)
CHP Mode Net Electrical
Efficiency at Proposed
Operational Plant Load
%
N/A
c)
CHP Mode Net CHP
Efficiency at Proposed
Operational Plant Load
%
N/A
d)
Reduction in Net Electrical
Output for CHP Mode at
Proposed Operational Plant
Load
MW
N/A
e)
Reduction in Net Electrical
Efficiency for CHP Mode at
Proposed Operational Plant
Load
%
N/A
f)
Reduction in Primary Energy
Usage for CHP Mode at
Proposed Operational Plant
Load
N/A
h)
Z Ratio
N/A
Requirement 4: Technical Provisions and Space Requirements
4.1
4.2
Description of Likely Suitable
Extraction Points
Description of Potential
Options which could be
incorporated in the Plant,
should be realised outside the
'CHP Envelope'
CHP ASSESSMENT
April 2014
Steam turbine extraction port/s. Hot reheat
inlet.
Thermal storage and/or stand-by boiler
systems could be utilised.
Seabank 3 Combined Heat and Power Assessment
4.3
4.4
Description of how the future
Costs and Burdens
associated with supplying the
Identified Heat Load /
Potential CHP Opportunity
have been minimised through
the implementation of an
appropriate CHP-R design
Minimisation of heat losses and best
technical approach has been used in order to
design the CHP extraction.
Provision of Site Layout of the
Plant, indicating Available
Space which could be made
available for CHP-R
Space should be taken into account for the
Heat Exchangers that exchange heat
between LP steam and water and space in
the steam turbine building as well as for the
piping that will transfer the fluid etc. See
indicative layouts below for single and multishaft configurations.
Requirement 5: Integration of CHP and Carbon Capture
5.1
5.2
a)
b)
c)
d)
e)
f)
g)
h)
i)
j)
k)
l)
m)
Is the Plant required to be
CCR?
Yes
Export and Return Requirements Identified for Carbon Capture.
A separate small CCGT unit has been taken into account to supply the heat for the
CCR as the steam extraction from the main CCGT STs has not been accepted. The
new CCGT will be named CHP2 as a reference
100% Plant Load
Carbon capture plant needs approx. 225kg/s
Heat Load Extraction for
of LP steam with an enthalpy of approx.
Carbon Capture at 100%
MW
2763KJ/kg. The above states that the thermal
Plant Load
load is approx. 621 MWth
Description of Heat Export
Heat will be extracted from CHP2 as LP
(e.g. Stream/Hot Water)
steam and directed to Carbon capture
Export Pressure
bar a 4.45
0
Export Temperature
C
154
Export Flow
t/h
810 t/h (225 kg/s)
Return Pressure
bar a 5.4
0
Return Temperature
C
138
Return Flow
t/h
810 t/h (225 kg/s)
Likely Suitable Extraction
There are no extraction points; a new CCGT
Points
(CHP2) has been taken into account.
Minimum Stable Plant Load.
The heat for the carbon capture is not extracted from the main CCGT so there is no
impact on it in any way, values remain the same.
Carbon capture plant needs approx. 225kg/s
Heat Load Extraction for
of LP steam with an enthalpy of approx.
Carbon Capture at Minimum
MW
2763KJ/kg. The above states that the thermal
Stable Plant Load
load is approx. 621 MWth
Description of Heat Export
Heat will be extracted from CHP2 as LP
(e.g. Stream/Hot Water)
steam and directed to Carbon capture
Export Pressure
bar a 4.45
0
Export Temperature
C
154
CHP ASSESSMENT
April 2014
Seabank 3 Combined Heat and Power Assessment
n)
o)
p)
q)
r)
5.3
a)
b)
c)
Export Flow
Return Pressure
Return Temperature
Return Flow
Likely Suitable Extraction
Points
t/h
bar a
0
C
t/h
810 t/h (225 kg/s)
5.4
138
810 t/h (225 kg/s)
There are no extraction points a new CCGT
(CHP2) has been taken into account.
Operation of Plant with Carbon Capture (without CHP).
The heat for the carbon capture is not extracted from the main CCGT so there is no
impact on it in any way, values remain the same.
Maximum Plant Load with
%
100
Carbon Capture
Carbon Capture Mode
Thermal Input at Maximum
MW
621 MWth
Plant Load
Carbon Capture Mode Net
Electrical Output at Maximum
MW
CCGT: 1160 MWe / peaking: 240 MWe
Plant Load
d)
Carbon Capture Mode Net
Electrical Efficiency at
Maximum Plant Load
%
CCGT: 58.09% / peaking: 37.36% / The total
efficiency will be between these two points.
e)
Minimum Stable Plant Load
with CCS
%
100
f)
Carbon Capture Mode CCS
Thermal Input at Minimum
Stable Plant Load
MW
621 MWth
g)
Carbon Capture Mode Net
Electrical Output at Minimum
Stable Plant Load
MW
CCGT: 794 MWe / peaking: 135 MWe
h)
Carbon Capture Mode Net
Electrical Efficiency at
Minimum Stable Plant Load
%
CCGT: 53.06% / peaking: 33.86% / The total
efficiency will be between these two points @
60% minimum load assumed
5.4
a)
Heat Extraction for CHP at 100% Plant Load with Carbon Capture [H].
The heat for the carbon capture is not extracted from the main CCGT so there is no
impact on it.
Maximum Heat Load
Extraction at 100% Plant Load MW
165 MWth
with Carbon Capture
b)
Maximum Heat Extraction
Export Flow with 100% Plant
Load with Carbon Capture
t/h
198 t/h (55 kg/s)
c)
Carbon Capture and CHP
Mode Net Electrical Output at
100% Plant Load
MW
Peaking output remains unchangeable,
CCGT: 1178 MWe
d)
Carbon Capture and CHP
Mode Net Electrical Efficiency
at 100% Plant Load
%
CCGT: 56.63%
CHP ASSESSMENT
April 2014
Seabank 3 Combined Heat and Power Assessment
e)
Carbon Capture and CHP
Mode Net CHP Efficiency at
100% Plant Load
f)
Reduction in Primary Energy
Usage for Carbon Capture
and CHP Mode at 100% Plant
Load
5.5
a)
b)
c)
%
CCGT: 63.67%
%
CHP-R guidance 2013 has been used.
CHPHȘ=63.67%
CHPEȘ=56.63%
RefHȘ=89%
RefEȘ=58.09%
The outcome gives 40.48%
Heat Extraction at Minimum Stable Plant Load with Carbon Capture.
The heat for the carbon capture is not extracted from the main CCGT so there is no
impact on it.
Maximum Heat Load
Extraction at Minimum Stable
MW
164 MWth
Plant Load with Carbon
Capture
Maximum Heat Extraction
Export Flow at Minimum
t/h
198 t/h (55 kg/s)
Stable Plant Load with Carbon
Capture
Carbon Capture and CHP
Mode Net Electrical Output at
Peaking output remains unchangeable,
MW
Minimum Stable Plant Load
CCGT: 763 MWe
Plant Load
d)
Carbon Capture and CHP
Mode Net Electrical Efficiency
at Minimum Stable Plant Load
Plant Load
%
CCGT: 51.04%
e)
Carbon Capture and CHP
Mode Net CHP Efficiency at
Minimum Stable Plant Load
%
CCGT: 60.77%
f)
Reduction in Primary Energy
Usage for Carbon Capture
and CHP Mode at Minimum
Stable Plant Load
%
CHP-R guidance 2013 has been used.
CHPHȘ=60.77%
CHPEȘ=51.04%
RefHȘ=89%
RefEȘ=58.09%
The outcome gives 35.96%
5.6
Can the Plant with Carbon
Capture supply the Selected
Identified Potential Heat Load
(i.e is the Identified Potential
heat Load within the 'CHP and
Carbon Capture Envelope')?
Yes
5.7
Description of Potential
Options which could be
incorporated in the Plant for
useful integration of any
realised CHP System and
The CHP thermal load can serve district
heating requirements or other process uses.
At the same time the plant can produce
electric power and the carbon capture plant
can work in parallel with no disruption as it is
CHP ASSESSMENT
April 2014
Seabank 3 Combined Heat and Power Assessment
Carbon Capture System
fed by a small separate CCGT unit (CHP2).
Requirement 6: Economics of CHP-R
6.1
Economic Assessment of
CHP-R
Suitable immediate heat loads have not be
identified so a full economic assessment has
not been undertaken at this stage. Qualitative
assessment of available heat loads are
included in the main body of this study.
BAT Assessment
Is the new plant a CHP plant
at the outset (i.e are there
economically viable CHP
opportunities at the outset)?
If not, is the new plant a CHPR plant at the outset?
Once the new plant is CHP-R,
is it BAT?
Figure 7: CHP Envelope
CHP ASSESSMENT
April 2014
No
Yes
Yes
Seabank 3 Combined Heat and Power Assessment
Figure 8: Indicative CHP Site Layout - Single Shaft Configuration
CHP ASSESSMENT
April 2014
45
Seabank 3 Combined Heat and Power Assessment
Figure 9: Indicative CHP Site Layout - Multi Shaft Configuration
CHP ASSESSMENT
April 2014
46