EASTHAM — Massachusetts has a problem, and Eastham is here to help.

The state’s Clean Energy and Climate Plan calls for net-zero greenhouse-gas emissions by 2050, which the plan says will require solar infrastructure that produces between 27 and 34 gigawatts (GW) of energy statewide.

Currently, Massachusetts has about 3 GW of solar infrastructure.

The problem, say members of the Eastham Climate Action Committee, is that there is a lot of confusion about solar energy. “We’ve heard from a lot of residents that they’re kind of interested in solar, but they don’t really understand it,” said Tom McNellis, a member of the committee and a former electrical engineer with Lockheed Martin.

McNellis and the rest of his committee believe that adopting solar power will help both the climate and townspeople.

Solar power has become increasingly affordable for homeowners. The National Renewable Energy Laboratory estimates that the cost of residential solar dropped from about $7.53 per watt produced in 2010 to $2.71 in 2020 — in other words, the cost of solar energy dropped by nearly two-thirds in those 10 years.

The environmental publication EcoWatch estimates that the average solar panel pays for itself within nine years in Massachusetts, and that the state’s average homeowner will save more than $33,000 over a lifetime by installing solar panels.

Despite these incentives, the adoption of solar in Eastham has declined in recent years. According to data on registered solar systems in Massachusetts, 117 residential solar systems were installed in Eastham in 2016. But from 2019 to 2021, fewer than 50 systems were installed each year.

A similar trend played out across the state, with the number of residential solar installations peaking in 2016 and dropping to less than half that rate by 2021.

Why residential adoption dropped off is unclear. McNellis speculates it may be that the state ran out of early adopters. There hasn’t been much of a push since the state’s “Solarize” campaign that lowered installation prices ended around that time.

Regardless of the reason, only about 8 percent of Eastham residences have solar panels on their roofs. “We think residents are missing out on savings,” McNellis said. “There’s enough clean energy right over our heads to power our homes. So why pay the electric company?”

On Oct. 28 the committee hosted a workshop at the Eastham Public Library in hopes of educating people about solar energy and the perks and challenges of adopting it. According to committee chair Roberta Longley, the event was a success, with 80 people attending. Over half reported that they plan on pursuing solar, Longley said.

Speakers included Lesley Maddalena, a solar specialist with the Mass. Dept. of Energy Resources; Mariel Marchand, a power supply planner with Cape Light Compact; and Megan Amsler, the executive director of the environmental nonprofit Cape & Islands Self-Reliance Corp. Industry vendors were noticeably absent.

That was on purpose, McNellis said. People “don’t want a sales pitch. They really are tired of marketing,” he said.

One part of the affordability picture is that the cost of solar panels can be offset partially by tax credits. The Residential Clean Energy Credit is a federal tax credit that allows you to claim up to 30 percent of the cost of a solar system. For the average residential system in Massachusetts, that comes to between $5,000 and $7,000.

The state offers a similar tax credit, though it’s for only 15 percent of the value of the system and maxes out at $1,000. Both tax credits can be claimed at once but apply only to taxes you owe.

In addition, any extra solar energy you produce is converted into net metering credits. These can be used to cover costs when energy consumption outpaces production, which can happen during winter’s short, cloudy days.

Still, the initial cost of putting in a system is high, McNellis admits — generally between $15,000 and $21,000, according to the solar marketplace EnergySage.

McNellis pointed to loan programs whose repayment plans approximately align with the payback period for the system that is installed. Local financial institutions like Cape Cod Five and Seamen’s Bank, as well as the multinationals, have loan programs that can cover solar panel installation costs. “You basically pay the bank instead of paying the utility,” McNellis said. “And from then on, you’re not paying anything.”

Not every house is right for a solar installation, McNellis said. The ideal roof faces south with little or no canopy cover, to capture as much daylight as possible. “We certainly don’t want people cutting trees down,” said McNellis.

Longley said that the committee does not want to push solar energy on residents. “There’s a lot of confusing information out there,” she said, especially concerning costs and financing. “We’re just trying to make it more accessible for people.”