By Lynn Ascrizzi
It’s odd to think that cold, underground temperatures can generate enough warmth to heat your home in winter. But that’s exactly the idea behind a geothermal heat pump system. Below-ground temperatures in Maine stay at a constant 45 to 50 degrees F.
Relatively speaking, that’s pretty warm, enough so, that a heat pump can pull the heat from either the ground or ground water and transfer it to a coil, which then will heat water or air in your home to approximately 120 degrees F.
A heat pump in your utility room works like a refrigerator, moving heat from one location to another. And, surprise! That same heat pump system, operated in reverse, can also air-condition your home.
The beauty of geothermal is that you never run out of the earth’s energy. What’s more, this energy-efficient system can save you thousands of dollars on fuel costs per year, reducing energy bills by 50-70%.
Benefits of a geothermal heat pump:
It is 48% more efficient than the best gas furnaces; is 75% more efficient than oil furnaces; can save you 50% of your water-heating bill, when combined with a hot water heating system; has low operating and low maintenance costs; and uses a renewable heat source.
A big obstacle to geothermal systems, however, is the significant, upfront expense to the homeowner—from $10,000 to $20,000 or more—depending upon local conditions and how much of the work you do yourself. Always consult with a reputable HVAC (heating, ventilation, air-conditioning) contractor to ensure that your system is installed properly. Depending upon the size of your home and installation costs, the pay-back period can be from two to 12 years. And, the more energy costs spike, the shorter the pay-back period. Moreover, a federal 30% tax credit for geothermal heat pumps is available through Dec. 21, 2016.
To learn more about federal credits for geothermal or solar, visit www.energytaxincentives.org. The Maine incentives are limited. Please check with Efficiency Maine before starting a project. Learn more at www.efficiencymaine.com/renewable-energy.
He’s getting a green pay back
Three years ago, a southern Maine resident opted to install a geothermal system at his owner-built home. A maintenance technician, he cut installation costs to about $10,000. But, to ensure proper installation of his open-loop, well-water-based system, he hired a local HVAC contractor to install the heat pump and to offer other technical advice.
The result? His LP gas home-heating costs dropped from $4,000 per year in 2008 to roughly $600 per year. And, his hot water bill was cut in half. It still costs him about $50 per month to fuel his gas stove.
Because the heat pump runs on electricity, however, his electric bill doubled. Yet, a geothermal system generates three-to-four times more heat energy than the electricity it uses. So his total energy savings per year is at least $3,000. He uses less BTUs to heat his home, and he creates less pollution. The estimated pay-back period for his system is three to four years.
