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STUDY OF MICRO COMBINED HEAT & POWER

ABSTRACT

Micro Combined Heat and Power (CHP) have been identified as a key element of the Energy Strategy offers environmental, economic and social benefits & fulfils the joint objectives of security of supply. However, in order to achieve the full potential for this technology, a number of regulatory and structural changes are required. This Presentation summarizes the potential, current status of micro CHP & how to implementing it into India.

Introduction• Micro CHP (combined heat and power) is the

simultaneous production of heat and power in a single building based on small energy conversion units.

• It generates electricity & heat at the same time. So, some of which you will use in your own home, the remainder it exported to the grid to be used by others. The heat produced is used for space and water heating.

• Micro-CHP, a cost-effective and flexible low carbon solution that generates heat and electricity on-site.

• Systems consist of a heat engine attached to a power generator that produces electricity.

• The system can be fuelled by a natural gas, biogas and liquid bio fuels.

• Micro-CHP systems are able to recover the waste heat from the engine (from the exhaust gases and the refrigeration circuits).

• This heat can then be used for several purposes such as space heating & others.

• The main output of a Micro-CHP system is heat with some electricity generation, at a typical ratio of about 6:1 for domestic appliances.

• The “micro” term is typically designated as less than fifteen kilowatts electric (<15 kW Elect.).

Advantages1. Costs, Savings, Earnings:• Save on electricity and fuels costs due to higher efficiencies.• Investment costs of micro-CHP are higher than those of a

conventional set-up, i.e. a boiler for heat and a grid connection for electricity.

• Operating costs can be lower, depending mainly on electricity tariffs and grid charges.

• Local generation of electricity is in some countries cheaper than buying it off the grid.

2. Environmental Impacts:• Usually lower to those of conventional and condensing

heating boilers.• Environmental impacts are reduced in proportion to the

efficiency gain and the reduction of fuel use.• Micro CHP systems can lead to GHG emission reductions by

avoiding generation of electricity in conventional power plants.

• The result depends on the energy 'mix' (the share of different types of power plants e.g. nuclear, coal, gas, renewable) of the country or region where the system is installed.

3. Efficiency:• Typically 70-80% of the energy value of the fuel is

converted to heat for central heating and hot water purposes & 10% and 25% is additionally converted to electricity, and the remainder (10-15%) is waste, lost with flue gases.

• Compared to the separate supply of heat by a conventional or condensing boiler and electricity from the grid, micro-CHP systems are more efficient.

Applications1. Organic Rankine Cycle mCHP2. Stirling Engine mCHP3. Fuel Cell mCHP4. Internal combustion engine (ICE) mCHP5. Micro turbines

Fuel Cell mCHP:• It is a solution that has high electrical efficiency and

therefore its output is much less determined by heat demand.

• As a result, this solution can provide a high level of power generation flexibility and create opportunities for enhanced demand response and combination with other distributed generators (e.g. heat pumps, vehicle to grid).

• In general terms, fuels cells combine a hydrogen based fuel input and gaseous stream containing oxygen.

• The products of this reaction vary for each type of fuel cell but typically are electrical power, heat, and water. In some instances, other product gases such as carbon dioxide are formed.

• PEMFC & SOFC have the Advantage to Utilize Natural gas directly into electricity & Continuous Heat output so use as a Micro CHP.

• Electrical Efficiency: 30-35%• Low Emissions• Low Temperature and Fast Startup• Mostly for continuous running apps• Some under development

• This low carbon technology is suitable for organizations with smaller buildings that need to use electricity and heat for long periods.

• Applying micro cogeneration can result in:1) Increased energy efficiency2) Reduced CO2 emissions3) Reduced energy costs4) Peak energy demand reduction

Typical applications include:1) Care homes2) Hotels3) Hospitals4) Office buildings5) Apartment blocks6) Laundries7) Retail stores8) Fast foods restaurants

Case Study for single family For ELECTRICITY

For 1st Room: -2 tube light, 1 fan & 1 acFor 2nd Room: - 2 tubelight &1 fanFor Drawing Room: - 2 fan, 2 tubelight, 1 TV & 1 chimneyFor kitchen: - 1 mixture, 1 fridge & 1 tubelight

Total KWH

Total tube light = 7*20W*4hour*300days = 168KWHTotal Fan = 4*80W*10hour*300days = 960KWHTotal AC = 1*1000W*2hour*300days = 600KWHTotal Fridge=1*1000W*24hour*300days = 7200KWHTotal Mixture = 1*100W*0.5hour*300days = 15KWH Total TV = 1*100W*8hour*300days = 240KWHTotal Chimney = 1*100W*8hour*300days = 240KWH

Total KWH/Annum = 9423 KWH/AnnumTotal KWH/Month = 785.25 ~ 785 KWH/Month

Charge on KWHFixed charge = 45/MonthVariable charge = (50*2.8) + (50*3.1) + (685*3.75) = Rs.2864/MonthSo Total cost = 2864+45 = Rs. 2909/MonthSo Total cost/Annum = Rs.2909*12 = Rs.34908/- = $588.17/-

For GasGas Charge = $ 5.01/unit = 5.01*62.54 = 313.3254 ~ Rs.314/-1 Therm = 100,000 BTUCost per therms = 0.42 to 1.10

For CookingIf we assume 1 unit is consuming per month then,Total therms consumed per day = 0.1111 therms/dayCharge of cooking Gas/Annum = 314*300/30 = Rs.3140/-

For HeatingIf we will heat a water to 60˚ up to 120˚ then,Cost = $0.5 - $14 per bathAverage we are taking = $3/bath & 0.12295 therms/bath used.Cost of heating/Annum = 3*62.54 = 187.62*4 person = 750*300 =Rs. 2, 25,000/-

Total Gas ChargeTotal Gas Charge/ Annum = Rs.3140 + Rs.225000 =Rs.2, 28,140/- =$3647.90/-So,Cost per therms = Total prize for gas / no. of therms consumed = (3647+3140) / (147.54+33.33) = 32.52/Annum = 3.25 / monthCost per KWH = Total prize for KWH / no. of KWH consumed = 34908/9423 = 3.70/Annum = 0.309/month

ConclusionFuel Cell Micro CHP offers a unique combination of heat and electricity generation which is perfectly adapted in household energy use. It is also used in isolated application on small scale. Micro CHP is likely to have a positive environmental impact with CO2 saving in the region of 20% of house hold emissions. Micro CHP has finally reached commercial reality, having faced and overcome significant technical, administrative and regulatory obstacles.

References

• http://www.rural-energy.eu/solutions/8/366/Micro-combined-heat-and-power-micro-CHP#.VNjpgz_nWCF

• http://www.qnergy.com/-micro-chp-system• http://www.cogeneurope.eu/micro-chp_269.

html• http://www.energ-group.com/ener-g-combin

ed-power/energy-services/micro-cogeneration/applications/

• http://www.baxi.co.uk/renewables/combined-heat-and-power.htm

• http://www.energystar.gov/ia/partners/pt_awards/documents/Marathon_Case_Study.pdf?20e3-8422

• http://www.b-es.org/sustainability/sustainable-technology-briefing-sheets/micro-chp-guidance/

• http://en.wikipedia.org/wiki/Micro_combined_heat_and_power

• http://www.marathonengine.com/cogeneration.html

• http://www.ecuity.com/wp-content/uploads/2013/03/The-role-of-micro-CHP-in-a-smart-energy-world.pdf

• http://www.microchap.info/benefits.pdf• http://www.energysavingtrust.org.uk/domesti

c/content/micro-chp• http://www.yougen.co.uk/renewable-energy/

Combined+Heat+'26+Power/• http://www.marathonengine.com/energy_sav

ings.html