By Mara Lee, The Hartford Courant
Geothermal heating and cooling systems work just as caves do: The temperature underground is more moderate than the air above. If it’s 85 degrees outside, it’s cool in the cave. If it’s 25 degrees outside, the cave is still 50 to 60 degrees.
In a home, office or church heated and cooled by a geothermal system, a pump brings 55-degree ground water up into a heat pump. The heat pump extracts heat from the water and sends cooler water back down into the earth. In the summer, the process is reversed: The pump pulls hot air from the house and sends it down into the earth.
Because geothermal heat pumps are more efficient than air-to-air heat pumps, and because the ground water is closer to the desired indoor temperature than the air outside, geothermal heat pumps use less electricity and work better in cold climates than the original heat pumps did.
“The heat pump works in the same manner as a refrigerator does in a home. You’re basically moving temperature from one place to another,” said Anthony Ganio, president of Connecticut Wells in Bethlehem, a company that specializes in drilling wells for geothermal systems.
He said there has been increasing demand for geothermal systems in the last half-dozen years. About 60 percent of the jobs are residential.
But the generous tax credits that pay for 30 percent of a geothermal system’s costs, funded by the stimulus bill, have not spurred a lot of work for his 16-person firm.
“I’d say we’re doing about half the residential work we did last year. It’s certainly slowed down,” he said. “It’s a direct result of the economy, especially the retrofit market. People have hard time spending $40,000 to $60,000 on a complete upgrade of their heating system.”
But once it’s in the ground, there are substantial savings. Ganio said someone with a 6,000-square-foot home could expect to spend $280 for electricity year-round.
“You compare that to someone who’s spending $350 to $500, even $700 a month to heat a building. It’s two-thirds less energy costs,” he said.
About 70 percent of the wells he drills are for new construction, and the rest are for retrofits. Most houses that convert already have ductwork; a geothermal system needs ductwork for air conditioning.
Marv Beloff, 81, chose geothermal for his new house on Beseck Lake in Middlefield eight years ago, and he is pleased he did.