Like ground-source heat pumps used in geothermal systems, air-source heat pumps extract heat by from the outside air, without the added expense of having wells drilled.
The air-source heat pump is made up of three components: the outside compressor, the line set, and the indoor evaporator or fan coil. The heat is then distributed using refrigerant, which transfers it inside or sends it outside depending on the season. While geothermal heating generally deals with underground heat at a constant temperature, the temperature above ground is always changing. Depending on how cold the weather is outside, the heating capacity will also fluctuate, making the appliance less efficient as the temperature drops. A 12,000 BTU/h (12 MBH) unit can heat up to 16,000 BTUs per hour when it is at least 20 degrees and 10 MBH when the temperature is down at -15.
While geothermal heating is in theory the most efficient heating source if installed correctly, that with the significant upfront costs ($25,000.00 or better) and challenges to designing geothermal systems correctly, air-source pumps are more accessible and cost effective to the average consumer. For a 15,000 BTU system rated to perform at -15, the average cost is about $3,500 to install after the Efficiency Maine rebates.
It also wasn’t until recently that air-source heat pumps were technologically able to perform in very cold weather, which makes them more desirable for homeowners in colder climates like in Maine. A new refrigerant was developed that allows the pumps to function at temperatures as low as -15 with no loss of efficiency. Fujitsu has been one of the leading manufacturers of products that use this technology.
Northern Energy Services began offering the Fujitsu Line of heat pumps over four years ago, but educating consumers about the technology has sometimes proven difficult. When many potential customers hear that it’s “electric” heat, they think of electric resistance heat, which has discouraged many homeowners from looking at heat pumps as a viable option. Also, there continues to be out of date or incorrect information on the internet about air sourced heat pumps which leads people to believe that heat pumps will not work effectively in Maine’s climate at low temperatures. What they need to realize is that heat pumps do not make heat as an oil furnace does, but rather transfer heat from one place to another much as a refrigerator removes the heat from the interior of the refrigerator to the outside of it.
According to University of Maine at Farmington Professor of Physics Paul Stancioff, while it costs an average of $38.10 per 1,000 BTUs to heat with electric resistance heat, it would cost around $35 to heat the equivalent amount with fuel oil. Air-source heat pumps, on the other hand, cost around $11.98 per 1,000 BTUs. Compared to electric resistance heat, which is 100-percent efficient, and fuel oil, which is around 80-percent efficient, the heat pump can exceed 300-percent efficiency in some cases, according to Efficiency Maine.
According to the Governor’s Energy Office, it currently costs about $3,011 a year to heat the average home with fuel oil using an Energy Star furnace or boiler, but according to Stancioff’s numbers, to run various systems on a very cold day at 20,000 BTUs for eight hours, it would cost $5.63 with fuel oil and $2 with a heat pump.
Unlike the geothermal systems, there are no federal and state tax incentives to purchase air source heat pumps. However, Northern Energy Services LLC does provide financial incentives through Efficiency Maine to install air sourced heat pumps in residential homes. Northern Energy Services LLC is also partnered with Efficiency Maine and Re New Financial to offer low-interest energy efficiency loans to finance efficiency projects like installing heat pumps after an energy audit is done. For more information on incentives and financing, contact us today
Northern Energy Services LLC exclusively installs Fujitsu “H” rated Heat pumps that continue to provide their rated output at -15 . For more information on the Fujitsu line, please go to http://www.fujitsugeneral.com