EGEE 102 Energy Conservation And Environmental Protection 9a Home Heating Systems Heating Systems EGEE 102 2 Heating Systems Some hot water systems circulate water through plastic tubing in the floor called radiant floor heating EGEE 102 3 Electric Heating Systems 1 Resistance heating systems Converts electric current directly into heat 1 usually the most expensive 2 Inefficient way to heat a building 2 Heat pumps Use electricity to move heat rather than to generate it they can deliver more energy to a home than they consume 1 Most heat pumps have a COP of 1 5 to 3 5 2 All air source heat pumps those that exchange heat with outdoor air as opposed to bodies of water or the ground are rated with a heating season performance factor HSPF EGEE 102 4 Geothermal Heat Pumps They use the Earth as a heat sink in the summer and a heat source in the winter and therefore rely on the relative warmth of the earth for their heating and cooling production Additional reading http www eren doe gov erec factsheets geo heatpumps html sidebar EGEE 102 5 EGEE 102 6 Geo Exchange Heat pump system Movie EGEE 102 7 World s Largest Heat Pump The Galt House East Hotel and Waterfront Office Buildings in Louisville Kentucky use a 4 700 ton GHP system to meet the heating and cooling needs of the complex The 750 000 square foot 70 000 square meter Galt House East Hotel completed in 1984 uses a 1 700 ton GHP system which cost 1 500 per ton to install http www eren doe gov geothermal geobasics html http www nrel gov data pix searchpix cgi getrec 3297896 display type verbose EGEE 102 8 This house in Aurora Colorado uses a geothermal heat pump system that will provide al the heating cooling and hot water needs For a home of 1 500 square feet with a good building envelope and a geothermal heat pump energy costs are about 1 a day EGEE 102 9 Cost Comparison Gwinnet GA Heating and Cooling Components Installation Costs 3 ton Addison heat pump 15 kW auxiliary heat Closed loop Central thermostat 4 700 increment over comparable system 3 600 indoor hard costs 2 766 ton 1 800 house incentive from Jackson EMC Operating Costs air source water source Heating 307 211 Cooling 252 230 Water heating 270 136 Annual total 1 073 577 5 84 year payback to recover 2 900 EGEE 102 10 EGEE 102 11 Benefits of a GHP System Low Energy Use Free or Reduced Cost Hot Water Year Round Comfort Low Environmental Impact Durability Reduced Vandalism Zone Heating and Cooling Low Maintenance EGEE 102 12 Solar Heating and Cooling Most American houses receive enough solar energy on their roof to provide all their heating needs all year Active Solar Passive Solar EGEE 102 13 Passive Solar A passive solar system uses no external energy its key element is good design House faces south South facing side has maximum window area double or triple glazed Roof overhangs to reduce cooling costs Thermal mass inside the house brick stones or dark tile EGEE 102 14 Passive Solar Deciduous trees on the south side to cool the house in summer let light in in the winter Insulating drapes closed at night and in the summer Greenhouse addition Indirect gain systems also such as large concrete walls to transfer heat inside EGEE 102 15 Passive Solar Heating EGEE 102 16 EGEE 102 17 Passive Heating Direct Gain Thermal W all Passive Cooling Shading Storage Suns pace Ve nt ilat io n EGEE 102 Earth Contact 18 Active Solar Heating Flat plate collectors are usually placed on the roof or ground in the sunlight The sunny side has a glass or plastic cover The inside space is a black absorbing material Air or water is pumped hence active through the space to collect the heat Fans or pumps deliver the heat to the house EGEE 102 19 solar water heater Active Solar Heating standby electric heater heat exchanger fan pump2 water tank pump 1 EGEE 102 20 Flat Plate Collector Solar Collectors heat fluid and the heated fluid heats the space either directly or indirectly EGEE 102 21 Efficiency of Furnace The combustion efficiency gives you a snapshot in time of how efficient the heating system is while it is operating continuously The annual fuel utilization efficiency AFUE tells you how efficient the system is throughout the year taking into account start up cool down and other operating losses that occur in real operating conditions AFUE is a more accurate measure of efficiency and should be used if possible to compare heating systems EGEE 102 22 Efficiencies of Home Heating 110 100 U S stock 7 90 80 70 1975 1976 building practice NAHB 60 LBL standard medium infiltration 50 LBL standard low infiltration 40 30 Brownell 20 Mastin 10 0 5 Phelps 0 2000 4000 6000 Saskatoon Ivanhoe Pasqua Leger Saskatchewan house Balcomb 8000 3 Btu ft2 per degree day Annual fuel input for space heat 106 Btu 1000 ft2 9 1 10 000 1 Btu ft2 per degree day EGEE 102 Degree days base 65 F 23 Tips Individual to Save Energy and Environment Set your thermostat as low as is comfortable in the winter and as high as is comfortable in the summer Clean or replace filters on furnaces once a month or as needed Clean warm air registers baseboard heaters and radiators as needed make sure they re not blocked by furniture carpeting or drapes Bleed trapped air from hot water radiators once or twice a season if in doubt about how to perform this task call a professional Place heat resistant radiator reflectors between exterior walls and the radiators EGEE 102 24 Use kitchen bath and other ventilating fans wisely in just 1 hour these fans can pull out a houseful of warmed or cooled air Turn fans off as soon as they have done the job During the heating season keep the draperies and shades on your south facing windows open during the day to allow sunlight to enter your home and closed at night to reduce the chill you may feel from cold windows During the cooling season keep the window coverings closed during the day to prevent solar gain EGEE 102 25 Close an unoccupied room that is isolated from the rest of the house such as in a corner and turn down the thermostat or turn off the heating for that room or zone However do not turn the heating off if it adversely affects the rest of your system For example if you heat your house with a heat pump do not close the vents closing the vents could harm the heat pump Select energy efficient equipment when you buy new heating and cooling equipment Your contractor should be able to give you energy fact sheets for different types models and designs to help you compare energy usage Look for high Annual Fuel