Abstract: . . .  may have a payback period in excess of 5 years. As electricity rates drop, this payback period will get longer and longer, unless equipment and installation costs drop dramatically. Energy Information Administration, Annual Energy Outlook 1994, DOE/EIA-0383(94) (Washington, DC, January 1994), Table 21. Groundwater temperatures hover around 50oF most of the year in most parts of the lower 48 States. For space heating, geothermal heat pumps have the second best average equipment efficiency of the major equipment types. 68 67 Energy Information Administration/ Renewable Energy Annual 1996 39 In a 1988 survey of GHP buyers, 97 percent said that they were happy with their purchase and would buy again. Approximate estimates of the total number of geothermal ground-coupled heat pumps installed and in use range between 100,000 and 350,000 residences in the United States, out of a total of about 100,000,000 residences.69 GHPs can be effectively used over the range of earth and air temperatures found in the United States, if designed and implemented properly. Economies of scale favor the conversion of large buildings with circulating water systems for heating and cooling. The heat pump itself operates on the same principal as the home refrigerator, which is actually a one-way heat pump. The GHP, however, can move heat in either direction. In the winter, heat is removed from the fluid and delivered into the home or building (heating mode). In the summer, heat is removed from the home or building . . .
. . .  drilling regulations. Typical loop installations have 50-year warranties. GHP installations are being actively promoted by a few investor-owned utilities and rural electrical cooperatives as a means of promoting energy efficiency and better managing demand. GHPs are estimated to cut 1 to 5 kilowatts of peak generating capacity requirement per residential installation. Since rural electric cooperatives often pay their electricity suppliers a rate based on the rate at the time peak load is experienced, shaving this peak reduces rates for all the members of the cooperatives. 69 Energy Information Administration, Annual Energy Outlook 1994, DOE/EIA-0383(94) (Washington, DC, January 1994), Table 21. 40 Energy Information Administration/ Renewable Energy Annual 1996  . . .
--3000,2,750,2438,17103