Methods of selecting sustainable clean energy technologies for the household,

community.

Lecture - 2

Energy consumption for• 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

• 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– Solar PV– MHP– Wind generator– Main grid

• Transportation– Vehicle running on biofuels– Electric vehicle– Hybrid vehicle– Mass transport (BRT on CNG,

electric train etc.)

STOVE EFFICIENCY AND COST

7

8

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

9

Mud ICS, metallic ICS, rocket stove

• Low cost• Fuel efficient• Easy to transport• Locally built• Accepted technology,

particularly in Terai

• 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.

• Increased thermal efficiency.• Reduced fuel wood

consumption• Less women’s drudgery• Reduced indoor air pollution• Prevention of fire hazards

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

Phakding

Lukla

SPACE HEATING DEVICES

LPG heater Electric heater

Beehive briquette heater

Biomass/ wood heater

WATER HEATER

• Solar water heater• Gas water heater• Electric water heater• Biomass water heater

SOLAR WATER HEATER

Solar thermal: Heating and Cooling

Pros• 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• 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 heaterPros• 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 heaterPros• 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 PVPros• 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

MHPPros• 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 horizontal-axis variety, and have multi-bladed 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– 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/#

37

Figure from the USA show the energy wasted in distributing it to sprawling markets.

http://camwest.pps.com.au/renewable-energy/

38

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/

Tasks• Calculate the energy cost per MJ and kWh for the following stoves:

– 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:– Solar water heater– LPG water heater– Electric water heater– Biomass water heater

SECTOR-WISE APPLICATIONS OF BIOMASS FUELS

S.N.

Sector Existing Fuels

Cost,NRs

Heating value

Emerging Fuels

Cost, NRs

Heating value

1 Domestic

• Fuelwood • Dung cake • Agri- waste • Agro crops • Charcoal • Biogas

4-6/kg---30/kg-

10-16 MJ/kg11 MJ/kg12 MJ/kg12 MJ/kg28 MJ/kg 23 MJ/kg

• Bee hive briquettes

• Rice husk briquette

• Wet briquette• Jatropha oil • Biohydro-carbon

oil

5/kg

15/kg

--45/l

18 MJ/kg

14 MJ/kg

12 MJ/kg46 MJ/kg46 MJ/kg

2 Commercial • Wood• Charcoal

4-6/kg30/kg

16 MJ/kg28 MJ/kg

• Producer gas• Municipal solid

waste

--

5-7MJ/m3

3 Industrial • Rice husk• Biogas

1.5 -2/kg-

13 MJ/kg23 MJ/m3

• Producer gas• Biogas

--

5-7MJ/m320MJ/m3

Values to be updated time to time

Operating energy cost per unit

Stove FuelDaily 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

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

Operating energy cost per unit

S.N. Stove FuelDaily fuel consumption, kg/L/m3/kWh

Annual consumption, kg/L/m3/kWh

Rate, Rs/kg,

Rs/L/kWh

Annual operational

cost, Rs

Heating value, MJ/kg , MJ/m3

Efficiency, %

Energy cost,

Rs/MJ

Energy cost,

Rs/kWh1 TCS Wood 7.5 2,738 10 27,380.00 15 0.07 9.52 34.292 ICS mud Wood 5 1,825 10 18,250.00 15 0.15 4.44 16.003 ICS, metallic Wood 5 1,825 10 18,250.00 15 0.15 4.44 16.004 ICS, metallic Briquette 2 1,460 10 14,600.00 15 0.15 4.44 16.005 Kerosene stove Kerosene, L 0.5 200 75 15,000.00 35 0.5 4.29 15.436 Biogas stove biogas, m3 1.1 394 75 29,565.00 20 0.45 8.33 30.007 LPG stove LPG 0.5 170 102 17,400.00 44 0.55 4.22 15.198 Induction stove Electricity, kWh 3 1,095 8 8,760.00 3.6 0.8 2.78 10.009 Gasifier Rice husk 3 1095 6 6,570.00 13 0.2 2.31 8.31

References

• http://www.iea.org/topics/cleanenergytechnologies/publications/cleanenergytechnologyinsightspapers/

• http://www.gvepinternational.org/sites/default/files/toolkit_-_review_of_household_clean_energy_technology_for_lighting_charging_and_cooking_in_east_africa_-_kenya_and_tanzania.pdf