DIRT-CHEAP HEAT FOR THE HOME

摘要

For energy-savvy homeowners, this may be the year to pull the plug on fossil fuels and journey toward the center of the earth. Geothermal heat (also known as ground source heat, orGSH) is breaking into the consumer market, already heating and cooling an estimated 850,000 U.S. households. The Department of Energy estimates that another 50,000 geothermal systems are installed annually.