The Maine Climate Council recently proposed that the State install at least 100,000 heat pumps by 2025 to help meet the state’s climate goals. The newest heat pump designs are much more effective at lower temperatures than past models, which is a good sign for Mainers. Heat pumps can be left on all year round, since they save heat down to at least 15 degrees Fahrenheit (10 degrees in some models). They can also provide cooling in the summer which will increasingly be a need in Southern Maine.
So, how do heat pumps work? Heat pumps work like a backwards refrigerator to extract heat from the outside air by compressing it and allowing it to expand once inside the building. By compressing air, the molecules move faster and warm up. When released to the room, they give off heat energy. Unlike other heating systems, heat pumps do not generate heat but use electricity to compress air and release it in a condenser. Heat pumps operate fans continuously to circulate air to a desired temperature in your building, so you will be paying for electricity, not fuel. I volunteer at the Gathering Place on Union St in Brunswick, behind Hannaford’s, which is heated entirely by three heat pumps powered with electricity from PV panels on the roof. Before the pandemic, 70 to 90 people came in and out daily. The temperature is set at 77 degrees F to provide comfort to guests who spend a lot of time outside.
An average home heat pump costs about $4,000 and will heat one large living area. Separate rooms not adjacent to the room with the heat pump can be heated either with electric units, in a bathroom for example, or with another heat pump, for example in the master bedroom. Several thousand Mainers last year received rebates from Efficiency Maine to reduce their heat pump costs, numbers that we hope will rise with the Climate Council’s recommendations. EM will give a rebate of $1000 for one heat pump or a maximum of $1500 for two or more heat pumps.
When my family replaced our oil furnace with 2 heat pumps, we also put in a heat pump water heater (HPWH). This unit gives us a larger supply of hot water and transfers some of the heat in our basement to the water tank. Dealers are now getting $750 rebates for HPWHs directly to save homeowners having that upfront cost. Maintenance for heat pumps is minimal annual cleaning, much less cost than maintaining a furnace that uses fossil fuels.
Check out www.efficiencymaine.org for a list of local heat pump dealers and the process to get your rebates for efficient space and water heating.
By: Nancy Chandler, Climate Action Advisory Team