Methods of selecting sustainable
clean energy technologies for the
household, community.
Lecture - 2
Energy consumption for
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Space heating
Lighting
Water heating
Cooling
Office equipment
Cooking
Refrigeration
Ventilation
Others
Selection criteria
• Available energy source
– Wind, MHP, PV, biomass, solar air, solar thermal etc.
• Cost analysis
– Cost of technology,
– Govt. subsidy
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GHG analysis
Financial summary
Sensitivity & risk analysis
Ease of operation, maintenance and repair
Clean energy technologies for household
• Cooking technology
– ICS, biogas
– LPG stove, natural
gas stove
– Solar cooker
– Electric hot plate,
induction cooker
• Heating technology
– Solar water heater
– Biomass heater
– LPG heater
• Electricity
– Solar PV
– MHP
– Wind generator
– Main grid
Clean energy technologies for household
Suppliers
• Reputable suppliers
Quality
• ISO certification
• NS mark
Clean energy technologies for community
• Cooking technology
– ICS, biogas
– LPG stove, natural gas
stove
– Solar cooker
– Electric hot plate, induction
cooker
• Heating technology
– Solar water heater
– Biomass heater
– LPG heater
• Electricity
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Solar PV
MHP
Wind generator
Main grid
• Transportation
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Vehicle running on biofuels
Electric vehicle
Hybrid vehicle
Mass transport (BRT on
CNG, electric train etc.)
STOVE EFFICIENCY AND COST
7
van der Horst, G.H. and A. J. Hovorka (2008) Reassessing the “energy ladder”: Household
energy use in Maun, Botswana. Energy Policy 36:3333-3344
8
Mud ICS, metallic ICS, rocket stove
• Increased thermal efficiency.
• Reduced fuel wood
consumption
• Less women’s drudgery
• Reduced indoor air pollution
• Prevention of fire hazards
• MICS is targeted for high
hills where ICS is
needed for cooking and
space heating.
• Especially Water tank is
used to tap waste heat
from MICS body.
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Low cost
Fuel efficient
Easy to transport
Locally built
Accepted technology,
particularly in Terai
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IMPROVED COOK STOVES
Benefits of ICS
• Reduction in biomass consumption for cooking purpose potential
for 20-40%reduction in fuel wood consumption.
• Improvement of Indoor environment and Health
– reduction of smoke in the kitchen/ house
– reduction in eye, skin and respiratory diseases
– Increased safety for small children
– Increased hygiene in the kitchen environment/ less soot on walls
• Decrease damage to tin roofs due to smoke.
• Reduction in work Loads
– reduction in workload for collecting fuel wood/time saving
– reduction in cooking time
– reduction in time in cleaning utensils , pots and pan
– reduction in cleaning the kitchen
– reduction in soot and smoke damage to clothes
Benefits of ICS
• Improvement of food and nutrition
– control of fire and food tastes better
– no need to eat left over food or under cooked food
• Employment opportunities
– Providing opportunities for skill development, self employment and
income generating activities -empowerment of women and rural poor
and building self reliance
– women and disadvantaged group's participation in decision making in
rural development
• Win-win benefits
– A win-win benefit is one in which a benefit in one way also gives a
benefit in another way.
– Both the environment and the communities involved benefit.
– Improved forest covers improves water retention and nutrition in the soil
– Properly managed forest improves biodiversity-both plant and animal
Disadvantages of ICS
• The baffle inside ICS has
to be repaired frequently
to maintain shape and
size to make ICS operate
efficiently
• The chimney should be
cleaned off soot every 2 3 months
• ICS have low space
heating efficiency
• Demands frequent repair
and maintenance works
Biogas plant
Advantages and Benefits of Biogas
• Provides a non-polluting and renewable source of
energy.
• Efficient way of energy conversion (saves fuelwood).
• Saves women and children from drudgery of collection
and carrying of firewood, exposure to smoke in the
kitchen, and time consumed for cooking and cleaning of
utensils.
• Produces enriched organic manure, which can
supplement or even replace chemical fertilizers.
• Leads to improvement in the environment, and
sanitation and hygiene.
• Provides a source for decentralized power generation.
• Leads to employment generation in the rural areas.
http://www.ecovillage.org.in/ecopedia/alternate-energy/advantages-and-disadvantages-of-biogas
Advantages and Benefits of Biogas
• Household wastes and bio-wastes can be disposed of
usefully and in a healthy manner.
• The technology is cheaper and much simpler than those for
other bio-fuels, and it is ideal for small scale application.
• Dilute waste materials (2-10% solids) can be used as in feed
materials.
• Any biodegradable matter can be used as substrate.
• Anaerobic digestion inactivates pathogens and parasites, and
is quite effective in reducing the incidence of water borne
diseases.
• Environmental benefits on a global scale: Biogas plants
significantly lower the greenhouse effects on the earth’s
atmosphere. The plants lower methane emissions by
entrapping the harmful gas and using it as fuel.
http://www.ecovillage.org.in/ecopedia/alternate-energy/advantages-and-disadvantages-of-biogas
Disadvantages of biogas
• Daily feeding including collection of more water.
• Enhances mosquito breeding in slurry areas.
• The process is not very attractive economically (as
compared to other biofuels) on a large industrial scale.
• It is very difficult to enhance the efficiency of biogas
systems.
• Biogas contains some gases as impurities, which are
corrosive to the metal parts of internal combustion
engines.
• Not feasible to locate at all the locations.
http://www.ecovillage.org.in/ecopedia/alternate-energy/advantages-and-disadvantages-of-biogas
Institutional cooking
Commercial stove
ESAP supported stove
Institutional cooking stove in use
INSTITUTIONAL SPACE HEATING
Lukla
Phakding
SPACE HEATING DEVICES
Beehive briquette heater
LPG heater
Biomass/ wood heater
Electric heater
WATER HEATER
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Solar water heater
Gas water heater
Electric water heater
Biomass water heater
SOLAR WATER HEATER
Solar thermal: Heating and Cooling
Pros
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Renewable. No fuels required.
Non-polluting. Carbon free except for
production and transportation
Inherently distributed with onsite production
Simple, low maintenance
Solar cooling is available when you need it
most
Hot water provide some limited storage
capacity
Operating costs are near-zero
Quiet. Few or no moving parts.
Mature technology
High efficiency
Modular systems
Can be combined with photovoltaics in highly
efficient cogeneration schemes.
Cons
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Intermittent
Low energy density
Does not produce electricity
Supplemental energy source or storage required for
long sunless stretches
Expensive compared to conventional water heaters
Construction/installation costs can be high
Harder to compete against very cheap natural gas
Some people find them visually unattractive
Manufacturing processes can create pollution
Installers not available everywhere
Generally not practical to store or sell excess heat
Produce low grade energy (heat vs. electricity)
Limited scalability
Dependent on home location and orientation
http://www.triplepundit.com/special/energy-options-pros-and-cons/solar-thermal-pros-cons-part-1-solar-heating-cooling/#
Solar cooling
Electric water heater
Pros
• No gas
• Easy install
• Energy efficient
• Space saving
Cons
• Limited output
• Won’t stay on during
power outages
• Cost
• Longer recovery time
https://www.acesolvesitall.com/plumbing/pros-cons-electric-water-heater/
Asis LPG Geyser
• Fully Automatic with battery
operated ignition.
• 20 minutes inbuilt timer.
• Hot water in 3 seconds.
• Saving up to 70%.
• Pressure release and drain
valve.
• Winter summer Knob.
• Water volume regulator.
• Gas volume regulator
http://www.indiamart.com/euro-hot/lpg-geysers.html
LPG water heater
Pros
• Energy efficient. Gas is
burnt when necessary.
• Installation easy and
simple like in electric
heater.
Cons
• Poisonous when the gas in
completely burned. It
releases CO and NOx.
• Costly.
Solar PV
Pros
• Clean energy. No combustion. No greenhouse
gas emission from use.
• Inexhaustible and abundant “fuel” supply
• Available nearly everywhere
• Well suited for distribution generation
• Technology exists today and is rapidly
improving
• Generates electricity directly from sunlight
• No moving parts required
• Power generation is silent. No noise or
pollution.
• Little or no transmission required
• Matches up well with air-conditioning need
• Require minimal maintenance
• Grants and incentives are sometimes available
• Excess heat can be used for co-generation
Cons
• Intermittent source. Not available at night or
under clouds.
• Relatively high cost, especially with storage
• Requires inverter to produce AC current
• Requires storage or grid connection for
continuous round-the-clock use
• Less available for heating demand (time of day
and season)
• Exotic materials required in many thin-film
systems
• Requires a relatively large amount of open
space
• Relatively low efficiency (around 17-40 percent)
• Relatively low energy intensity ( ~8-12 m2/ kW)
• Fragile materials
• Possible aesthetic issues
• Technology risk: a much better system might
come out next year
http://www.triplepundit.com/special/energy-options-pros-and-cons/solar-photovoltaics-pros-cons/#
Solar home system – Off grid pv system
MHP
Pros
• MHP is decentalised, renewable,
robust, and simple technology.
• No reservoir required
• Electricity can be delivered as far as 1
km away to the location where it is
being used
• MHP is considered to function as a
‘run-of-river’ system
• Due to the low-cost versatility and
longevity of MHP, developing
countries can manufacture and
implement the technology to help
supply much needed electricity to
small communities and villages
• Integrate with the local power grid.
Cons
• MHP plants require certain site
conditions and are thus not suitable
for any location (Suitable site
characteristics required).
• The size and flow of small streams
may restrict future site expansion as
the power demand increases.
• Electricity generation is highly
dependant on an constantly sufficient
river discharge. In many locations
stream size will fluctuate seasonally.
That is less power generation in dry
season.
• Environmental impact. Proper caution
must be exercised to ensure there will
be no damaging impact on the local
ecology or civil infrastructure.
https://energypedia.info/wiki/Micro_Hydro_Power_(MHP)_-_Pros_and_Cons
Wind power
Pros
• Enormous potential
• Wind energy is clean and safe.
• Wind energy is a domestic source of
energy. Wind energy and other renewable
energy sources can improve a nations
degree of self-sufficiency.
• Wind turbines can be installed fast.
• Wind turbines can be used competitively as
a dispersed energy production technology
in areas with dispersed electricity
consumption.
• Wind power is not only applicable in the
industrialized areas and countries, but is an
ideal technology for the electrification of
rapidly industrializing countries.
Cons
• Unpredictable
• Heavy upfront cost
• Noise emission
• Visual impact on
landscape (looks)
• Moving shadows
• Erosion
• Impact on birds and
bats
• Interference with
electromagnetic
communication
• Personnel safety
Wind pump
• Most windmills for water-pumping
applications are of the horizontalaxis variety, and have multibladed rotors that can supply the
high torque required to initiate
operation of a mechanical pump
• Wind pumps are used to pump
water for a variety of applications
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Domestic water supply
Water supply for livestock
Irrigation
Drainage
Salt ponds
Fish farms
Wind pump vs solar pump
• In general, mechanical windmills and solar pumps are best
for small quantities of water and low pumping heads.
• Both solar- and wind-powered pumps are commercially
available, but solar pumps have some distinct advantages.
• Solar-power systems collect energy even when it's cloudy
outside, while wind systems rely on gusty conditions for peak
efficiency.
• Solar-power systems also often cost less than wind systems,
and are less expensive to maintain.
• Solar systems are also more mobile than wind systems,
which, in most cases, have to be mounted in a stationary
position with a concrete base.
Fundamental Problems of Multi-bladed Wind pumps
• Inefficient Rotor
– The main design feature of a multi-bladed rotor is "high starting torque", which
is necessary for cranking a piston pump operation. Once started a multi-bladed
rotor runs at too high a tip speed ratio at less than its best efficiency of 30%.
• Poor load matching
– A multi-bladed windmill is a mechanical device with a piston pump. Because a
piston pump has a fixed stroke, the energy demand of this type of pump is
proportional to pump speed only. On the other hand, the energy supply of a
wind rotor is proportional to the cube of wind speed. Because of that, a wind
rotor runs at over speed (more speed than needed), yielding a loss of
aerodynamic efficiency.
• Cyclic torque variation
– A piston pump has a very light suction phase, but the upstroke is heavy and
puts a big back torque on a starting rotor when the crank is horizontal and
ascending. A counterweight on the crank up in the tower and yawing with the
wind direction can at least spread the torque to the crank descent.
https://en.wikipedia.org/wiki/Windpump
Hybrid PV Systems
A hybrid PV system is basically a grid-tie and off grid PV system combined. It is a system that is attached to
the grid but when the grid goes down the inverter switches over to the battery bank
• Pros: This system is good/ best for areas where you have grid power but the grid goes down often.
• Cons: Very expensive and requires regular maintenance.
http://sol-energy.us/~solenerg/index.php/pros-and-cons-of-grid-grid-tie-and-hybrid-pv-systems.html
Hybrid power system
• Energy sources
– Sun
– Wind
– Fossil fuel
• No sun, no wind then
generator can be used.
• Depending on weather
condition solar and
wind energy can be
harnessed.
• It is expensive system
but reliable.
http://www.howtosolarpoweryourhome.com/solar-system-for-home-electricity/#
Figure from the USA show the energy wasted in distributing it to sprawling markets.
http://camwest.pps.com.au/renewable-energy/
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Challenges with renewable energy
• The EPR or the EROEI (Energy Profit Ratio or the Energy Returned on
Energy Invested) for renewable energy is low, but also must include the
EPR for the fossil fuels that are needed to mine, transport, and refine the
materials to manufacture, and to install the needed infrastructure.
• An example is a large wind turbine. The tower alone contains some 22
tonnes of steel, the foundations contain many tonnes of concrete and we
need some 1000 such wind turbines to replace one medium-sized coal-fired
power station. And they only produce electricity when the wind blows. The
turbine’s blades are high-tech devices as are the rare-Earth metals-based
generators, both requiring high energy inputs.
• Also needed, and to be counted in the EPR equation, is the transmission
infrastructure to transport the electricity from the generation areas to
markets.
• As the EPR on fossil fuels declines the EPR on renewable energy
production declines.
http://camwest.pps.com.au/renewable-energy/
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Tasks
• Calculate the energy cost per MJ and kWh for the following stoves:
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Traditional stove
Improved cook stove (mud)
Improved cook stove (metal)
Briquette stove
Gasifier stove
Kerosene stove
Bio-gas stove
LPG stove
Electric stove
• What are the possible space heating technology that can be used in rural
mountain? Discuss.
• Describe the pros and cons of the following water heater:
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Solar water heater
LPG water heater
Electric water heater
Biomass water heater
SECTOR-WISE APPLICATIONS OF BIOMASS FUELS
S.
N.
1
Sector
Domestic
Existing
Fuels
Cost,
NRs
Heating
value
Emerging
Fuels
Cost,
NRs
Heating
value
• Fuelwood
• Dung cake
• Agri- waste
• Agro crops
• Charcoal
• Biogas
4-6/kg
30/kg
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10-16 MJ/kg
11 MJ/kg
12 MJ/kg
12 MJ/kg
28 MJ/kg
23 MJ/kg
• Bee hive
briquettes
• Rice husk
briquette
• Wet briquette
• Jatropha oil
• Biohydro-carbon
oil
5/kg
18 MJ/kg
15/kg
14 MJ/kg
45/l
12 MJ/kg
46 MJ/kg
46 MJ/kg
2
Commercial
• Wood
• Charcoal
4-6/kg
30/kg
16 MJ/kg
28 MJ/kg
• Producer gas
• Municipal solid
waste
-
5-7MJ/m3
3
Industrial
• Rice husk
• Biogas
1.5 -2/kg
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13 MJ/kg
23 MJ/m3
• Producer gas
• Biogas
-
5-7MJ/m3
20MJ/m3
Values to be updated time to time
Operating energy cost per unit
Stove
Fuel
TCS
Wood
ICS mud
Wood
ICS met.
Wood
ICS met.
Briquette
Gasifier
stove
Rice husk
Kerosene
stove
Kerosene,
L
Biogas
stove
Biogas,
M3
LPG stove
LPG
Induct.
stove
Electricity,
kWh
Daily
consumption,
kg/L/m3/kWh
Annual
consumption,
kg/L/m3/ kWh
Rate,
Rs/kg
Annual
operating
cost, Rs
Heating
value,
MJ/kg or
MJ/m3
Thermal
efficiency,
%
Energy
cost,
Rs/MJ
Energy
cost,
Rs/kWh
Operating energy cost per unit
Daily fuel
S.N. Stove
Fuel
consumption,
kg/L/m3/kWh
1 TCS
Wood
7.5
2 ICS mud
Wood
5
3 ICS, metallic
Wood
5
4 ICS, metallic
Briquette
2
5 Kerosene stove Kerosene, L
0.5
6 Biogas stove
biogas, m3
1.1
7 LPG stove
LPG
0.5
8 Induction stove Electricity, kWh
3
9 Gasifier
Rice husk
3
Rate,
Annual
consumption, Rs/kg,
kg/L/m3/kWh Rs/L/kW
h
2,738
10
1,825
10
1,825
10
1,460
10
200
75
394
75
170
102
1,095
8
1095
6
Annual
Heating value,
Efficiency,
operational
MJ/kg ,
%
cost, Rs
MJ/m3
27,380.00
15
0.07
18,250.00
15
0.15
18,250.00
15
0.15
14,600.00
15
0.15
15,000.00
35
0.5
29,565.00
20
0.45
17,400.00
44
0.55
8,760.00
3.6
0.8
6,570.00
13
0.2
Energy
cost,
Rs/MJ
9.52
4.44
4.44
4.44
4.29
8.33
4.22
2.78
2.31
Energy
cost,
Rs/kWh
34.29
16.00
16.00
16.00
15.43
30.00
15.19
10.00
8.31
References
• http://www.iea.org/topics/cleanenergytechnologies/p
ublications/cleanenergytechnologyinsightspapers/
• http://www.gvepinternational.org/sites/default/files/to
olkit__review_of_household_clean_energy_technology_f
or_lighting_charging_and_cooking_in_east_africa__kenya_and_tanzania.pdf