As Massachusetts races to wean utilities off fossil fuels in order to hit its climate targets, the municipal light companies that provide electricity to some 50 communities collectively have far less clean energy in their portfolios than the major for-profit utilities.

That’s the upshot of a new report from the Massachusetts Climate Action Network, which found, for example, 33 of the municipal providers had less than 1 percent of clean energy sources such as wind and solar in 2020.

While some communities are far ahead of others, particularly Concord, Belmont, and Wellesley, overall just 2.43 percent of the total energy mix at the 40 municipal light companies assessed in the report are from clean energy.

Known as municipal light plants, the community utilities combined had about 420,000 customers as of 2019, and provide roughly 14 percent of the state’s energy supply, said Logan Malik, lead author of the report and clean energy director for MCAN, a climate advocacy organization.

“We are seeing leaders — when you look at Concord, when you look at Belmont, when you look at Wellesley, those are three great examples,” Malik said. “But at the same time, because of the lack of regulation and because of the lack of support, we’re seeing that it’s not translating in every instance. And that has real implications for the Commonwealth’s transition to a clean and just energy future.”

The report found that despite the slow progress on cleaning their energy mix, many municipal light plants are technically on track to reach emission goals set for them in the state’s most recent climate law passed in 2021, thanks to a special standard that allows them to include nuclear energy in their calculations, while investor-owned utilities like Eversource or National Grid cannot.

Taking that into account, the report found that 38 percent of the energy mix from municipal light plants is considered “non-emitting.” That sizable percentage comes largely from contracts that municipal light plants have held with the Seabrook Station nuclear power plant in New Hampshire and the Millstone Unit 3 power plant in Connecticut, both of which came online more than three decades ago.

Malik said in his report that the use of nuclear power is also a concern. He wrote of the need for municipal utilities “to rapidly transition away from fossil fuel sources while also recognizing the danger that nuclear energy poses to communities, both in the operation of nuclear facilities as well as in the storage and disposal of nuclear waste.”

Kate Roy, spokesperson for the Massachusetts Municipal Wholesale Electric Company, a nonprofit quasi-state agency that works on behalf of 20 municipal utilities, said the organization is committed to “goals to get to net zero carbon emissions by 2050″ and to “helping the MLPs get there.”

Massachusetts has long required investor-owned utilities to hit annual benchmarks for renewable energy, starting at 1 percent in 2003 and growing to 20 percent this year. But municipal light plants are exempt, and until last year were allowed to meet their energy demands by focusing solely on affordability and reliability.

“Some municipal light plants went out and procured green, renewable electricity,” said Amy Boyd, director of policy at the Acadia Center.

But many then sold off the credits for that energy to investor-owned utilities required to green their portfolios, she added. The income from the sale of the credits meant the municipal light plants were able to lower energy costs for their rate payers, but they weren’t able to count that renewable energy as part of their energy portfolio, because it cannot be double-counted.

The practice of selling, rather than using, renewable credits has contributed to residents in communities with municipal light plants, who on average already have substantially higher median incomes than the rest of the state, having lower energy costs, according to the report.

But the passage of the 2021 Next Generation Roadmap for Massachusetts Climate Policy bill for the first time required municipal light plants to meet emissions thresholds, although it did not limit their use of nuclear energy.

Having a municipal light plant has allowed some communities, like Belmont, to go above and beyond on renewables. Belmont Light, which in 2020 had more than 17 percent clean energy sources and 33 percent of noncarbon-emitting sources, is working toward a fully nonemitting power portfolio by the end of the year, said general manager Craig Spinale. He said that having a Power Supply Policy, which is a transparent and public plan for a clean energy transition, is helping Belmont stay on track.

Clean energy advocates say the structure of the muni-utilities offers an opportunity. In most cases, the plants are run by commissioners who are elected, and those little-watched races may hold great potential for clean energy.

“So many of the decisions are made at the commissioner and board level,” said Casey Bowers, of the ELM Action Fund, which supports progressive candidates running for municipal light board seats. “In some of these races that we’ve been looking at, the winning vote tally is 2,500 or 2,000, so you’re really talking about a local level where every vote truly matters and really does have a say in the direction of the MLP.”

Read the full article in The Boston Globe here.