Climate Change is the biggest challenge of today Mankind. Until now, there is not an easy solution And the only way out is an strong reduction of CO 2 and other green house gases emission all around the world.
Heat Pumps and CHP for the Climate Protection Fabián Guzmán Betreuer: Johannes Henkel 14.12.2007
Heating Energy Residential Energy Distribution 80% 70% 60% 50% 40% 30% 20% 10% 0% 76% 12% 4% 6% 2% Space Heating Hot Water Process Heat Electricity Light Energy use in the residential sector, which accounted for about 34 percent of worldwide delivered energy consumption in 2004, is defined as the energy consumed by households, excluding transportation uses. [EIA, USA 2006] 1/20
Heat Pumps An electric device with both heating and cooling capabilities. It extracts heat from one medium at a lower (the heat source) temperature and transfers it to another at a higher temperature (the heat sink), thereby cooling the first and warming the second. [EPA] How does it work? 2/20
Characteristics There are 2 kind of heat pumps: Compression HP or absorption cycle HP. Working Fluids: Ammonia, CO 2, Water, Hydrocarbons, HCFC s, HFC s and mixtures. Heat Sources: Heat source Ambient air Exhaust air Ground water Lake water River water Sea water Rock Ground Waste water Temperature Range ( C) 10-15 15-25 4-10 0-10 0-10 3-8 0-5 0-10 >10 3/20
Types of Heat Pumps Heating-only heat pumps, providing space heating and/or water heating. Heating and cooling heat pumps, providing both space heating and cooling. Integrated heat pump systems, providing space heating, cooling, water heating and sometimes exhaust air heat recovery. Heat pump water heaters, fully dedicated to water heating. (normally as an auxiliary equipment) 4/20
Efficiency Coefficient of Performance (COP) COP = Heat Delivered Electricity supplied Typically between 3 6 Depends on the temperature range 5/20
Advantages Disadvantages Short capital recovery time (3-5 years). Energy efficient. Environmentally friendly Lower Energy costs. Simple equipments. Heating and cooling operations are possible in one machine. Not big scale units available. Due to the number of components maintenance may be needed. Secondary or backup heat sources are required in cooler climates. There is not always an adequate heat source. 6/20
Reduction CO 2 Emissions 1 MWh heat Conventional heating systems with Heating oil 400 Kg CO 2 Electric heater 810 Kg CO 2 Coal 740 Kg CO 2 Natural Gas 320 Kg CO 2 1 MWh heat From a heat pump with COP= 4 and electricity from Coal 230 Kg CO 2 Natural Gas 130 Kg CO 2 COP= 5 and electricity from Coal 184 Kg CO 2 Natural Gas 104 Kg CO 2 Reduction between 35-68% 7/20
Combined Heat and Power (CHP) Combined heat and power (CHP) technologies produce both electricity and steam from a single fuel at a facility located near the consumer. These efficient systems recover heat that normally would be wasted in an electricity generator, and save the fuel that would otherwise be used to produce heat or steam in a separate unit. 8/20
How does it work? 9/20
Internal Types Prime Movers :Big and medium capacity reciprocating engines (5kW-7MW) Microturbines (25 500kW) Industrial gas and steam turbines (0,5 25MW) Fuel cells (1kW-10MW) Mini and Micro CHP (10-90kW) combustion engines, stirling engines, steam engines, microturbines, fuel cells 10/20
Utilisation Big CHP plants are used for electrical power production and distribution through pipes to heat local housing. The biggest commercial steam system in the world produces 17 million tons of steam each year through its seven cogeneration plants before pumping it to 100,000 buildings in Manhattan. Medium Capacity systems are used locally and common applications are Industrial manufacturers - chemical, refining, ethanol, paper, food Institutions - universities, hospitals, prisons, military bases Commercial buildings hotels, casinos, airports, office buildings, nursing homes Municipal - district energy systems, wastewater treatment facilities, schools Residential - multi-family housing, planned communities Small and compact equipments are applicable to domestic uses in individual households. 11/20
CHP in Europe 2004 12/20
CHP in Germany Today share of CHP electricity in Germany is about 13% Fuel taxes advantages and fixed electricity prices. The new CHP law has the objectives: Modernization of the working Plants to achieve higher efficiencies. Change in fuels from coal to gas or biomass in order to reduce the CO 2 emissions Raise the participation to 25% of elec. Production before 2020. 13/20
Efficiency Total reduction of fuel of about 40%. 14/20
Advantages Disadvantages Possible use from personal units until big scale plants. Energy efficient. Environmentally friendly Lower Energy costs. Ratio Elec./Heat is not easy to handle Efficiency reduces with long pipe nets distances Rolling equipments may need maintenance and lubrication. Higher installation costs 15/20
Reduction CO 2 Emissions 1 MWh heat 0,8 MWh Electric power Conventional systems with 1 MWh heat 0,8 MWh Electric power η CHP= 80% Heating oil 816 Kg CO 2 Coal 1156 Kg CO 2 Natural Gas 736 Kg CO 2 Coal 736 Kg CO 2 Natural Gas 416 Kg CO 2 Reduction between 35-50% 16/20
17/20
18/20
Comparison Heat Pumps have a better environmental performance ( CO 2 emissions), but they are only available for relatively small amounts of energy. CHP saves fuel and avoid CO 2 emissions with a high efficiency if the heat is needed at the time the electricity is produced. As mass consumption equipments (individual households) heat pumps result cheaper. CHP is used to produce big amounts of heat as delivered energy, so the environmental and cost advantages may be escalated to big values. 19/20
Sources Enviromenta Protection Agency, USA www.epa.gov International Energy Agency www.iea.org International Energy Agency Heat Pump Centre - www.heatpumpcentre.org/ Wissenschaftlicher Beirat der Bundesregierung Globale Umweltveränderungen 2003- www.wbgu.de/wbgu_jg2003.pdf Energie Agentur Nordrhein-Westfalen - www.energieagentur.nrw.de United States Clean Heat and Power Association- www.uschpa.org/ Bundesverband Kraft-Wärme-Kopplung e. V.(B.KWK) - www.bkwk.de European Enviromental Agency - www.eea.europa.eu European Federation of public service unions - www.epsu.org 20/20
Thank you for your attention