People think Manhattan is inhospitable to geothermal energy because it is built on bedrock. But granite is excellent for transferring heat. The gravel and sand of Brooklyn and Queens are even better. Cost efficiency dwindles with increasing size. The geothermal payback can take at least three years.
Some utility companies provide grants or rebates to encourage homeowners to go geothermal.
I was a believer all along, but I never thought it would be possible financially. In the summer, there is a bonus. The circulating water absorbs the house's heat and can, in turn, heat his water supply free. On a frigid morning last week, Mr. Soobitsky said he was thankful for an electric heater, which turns on automatically when temperatures remain below freezing. Geothermal heat tends to be frustratingly even, and complaints focus on its inability to make a room toasty warm.