Heat Pump Services
in Harpswell, Maine

Of Harpswell's roughly 128 square miles, only about 24 are land; the rest is Casco Bay. The town runs down Harpswell Neck and across Sebascodegan Island, which locals call Great Island, plus Orr's Island and Bailey Island, all joined by bridges, with ninety-five smaller islands inside the town line as well. Nine villages, from Cundy's Harbor to West Harpswell and South Harpswell, are strung along those necks. Very few homes sit far from salt water, so wind exposure and damp air shape how a house holds its heat. Cumberland County, Harpswell included, falls in IECC climate zone 6, the band used for most of Maine.

Of roughly 4,300 housing units the Census Bureau American Community Survey (2020–2024) finds in Harpswell, only about 2,600 are occupied as somebody's usual home, which means roughly four in ten were vacant or used seasonally when surveyed. Across Cumberland County the comparable figure is closer to one in seven. Among the homes that are lived in year-round, about 91% are detached single-family houses and 83% are owner-occupied. The median home dates to about 1979, roughly a fifth were built before 1940, and fewer than one in five went up after 2000.

Heating is where Harpswell stands apart from the rest of the county. Utility gas is essentially absent, under 1% of homes, and none of the four gas utilities regulated by the Maine Public Utilities Commission names Harpswell in its territory. Oil heats about 44% of occupied homes and propane about 34%, two and a half times the Cumberland County propane share of 13.5%. Close to one household in ten burns wood as its primary fuel, and electricity, which counts heat pumps and baseboard together, for only about 7%.

That reliance on delivered propane makes Efficiency Maine's own cost comparison especially relevant here. At prices as of June 18, 2026, with propane at $3.34 a gallon and electricity at $0.27 per kWh, the program estimates heat pumps save about $1,387 a year compared with heating by propane. Your own figure will depend on the house, its insulation and how you use it.

Permits and floodplain questions go through Harpswell's Code Enforcement Office, and for a shoreline lot it pays to ask early whether the property sits in a mapped flood zone before choosing where outdoor equipment goes. Southern Maine Heat Pumps, a family-owned Gorham company, offers free in-home estimates on the necks and islands. See our Brunswick service area page, read about ductless mini-splits for Harpswell homes, or request a free estimate.