Geothermal

Efficiency

Geothermal heat pumps are much more efficient than air source heat pumps because earth temperatures are much more uniform through the year than air temperatures. Not only are earth temperatures more constant, but also the range of temperatures in ground water is rather small in the United States, varying from upper 40s to upper 70s nationwide.

To further improve efficiency, many manufacturers use variable-speed, electronically-controlled motors on the duct system fans. Depending on unit size, manufacturers may opt for reciprocating, inertia, rotary, or scroll compressors — all of which are hermetically sealed and mounted in the indoor cabinet. Some advanced heat pumps feature two-speed or variable speed operation while others feature dual compressors to vary output capacity and match loads.

The Benefits Speak for Themselves

Tens of thousands of homes are being built or retrofitted with geothermal heating and cooling systems every year, because of the advantages these systems offer: economical operation, noise reduction, and product quality. Initially reserved for the most expensive homes, now these systems have become affordable options for thousands of low and moderate income housing units because of the system’s low life cycle costs compared to all other alternatives in almost every region of the country. According to the Environmental Protection Agency, geoexchange systems save homeowners more than 30-70% in heating costs 20-50% in cooling compared to conventional systems.

Geothermal Heating and Cooling Makes Sense

Geothermal systems are efficient, environmentally-sensitive, comfortable, and economical. Operating savings often provide paybacks of considerably less than five years — sometimes less than two years. The key is that geothermal heat pumps use electricity to move heat, not to generate it by the burning fuel or using electric resistance elements. Indeed, the U.S. EPA has found that no other technology with more favorable operating efficiencies and economics than emerging geothermal heat and cooling systems.

An Important Renewable Energy Technology

The U.S. Environmental Protection Agency has concluded that well-designed and properly installed high efficiency geothermal heat pump systems produce less environmental harm than any other alternative space conditioning technology currently available. On a full fuel cycle basis, emerging geothermal systems are the most efficient technology available, with the lowest CO2 emissions for minimum greenhouse warming impact. Overall, the EPA found emerging geothermal heating and cooling systems to have the lowest environmental cost of all technologies analyzed — including air-source heat pumps and natural gas furnaces.