Green Municipal Aggregation

Want to live in a greener community?

Want to live in a greener community?

Support Green Municipal Aggregation (GMA), also known as community choice aggregation or CCA, in your community to green up the electricity for all residents.

The latest on GMA: Read our blog

What is GMA?

Since 1997, Massachusetts state law allows a city or town to choose the electricity supplier for residents and businesses within that municipality. This is called municipal aggregation or community choice aggregation. It allows for important energy decisions to be made at the local level rather than by an investor-owned utility or by a for-profit competitive electricity supplier. The oldest and largest example in Massachusetts is the Cape Light Compact, which buys electricity and runs energy efficiency programs for all the towns on Cape Cod plus Martha’s Vineyard. 

GMA, Green Municipal Aggregation, is a model devised by Green Energy Consumers and Good Energy that adds more renewable energy to residents' electricity at a competitive price. When a community decides to enact GMA, it goes out to bid for an electricity supplier and secures a long-term price and a cleaner electricity supply. That supplier replaces the utility's Basic Service, and offers a more stable price (usually cheaper in the long run, too) right on everyone's regular electricity bill.

Read our Report on Green Municipal Aggregation in Massachusetts

Green Energy Consumers' new paper explains the nuts and bolts of Green Municipal Aggregation (GMA) and how several MA communities are using it to drive demand for new renewables. Lessons learned can apply to Rhode Island and other states.

Read the report

What makes it really green?

In our GMA model, a community takes the opportunity offered by municipal aggregation to increase the renewable energy content of residents' electricity supply above and beyond what is required by state law. Both Massachusetts and Rhode Island have laws requiring that our electricity must come from an increasing percentage of qualifying “Class I/new renewables,” such as wind and solar, but even with these laws, the pace is too slow to meet the challenge we face from climate change.

With GMA, a community can add at least five percent (5%) more Class I/new renewable energy into the community's electricity supply than required by law. That means a community can jump years ahead of state law, sending a message to policymakers that residents want more renewable energy, faster. In Massachusetts, several communities have added 5% more than required by law. Brookline has added 25%!

Why just 5%

Buying Renewable Energy Certificates, or RECs, from Class I/new renewable energy generators provides developers a source of revenue needed to ensure project financing. So when a community enacts GMA, it is essentially helping projects get built and shifting our power grid away from fossil fuels. Class I/new RECs are more expensive than non-Class I/new RECs, but have a much stronger impact on the power grid. The object of the game is to add wind and solar so that they displace fossil fuels.

An increase of five percent supports a significant amount of renewable energy on our power grid while keeping the new electricity supply price competitive with electricity that merely complies with state requirements. In 2018, the Massachusetts the Class I requirement is just 13% and the Rhode Island “new” requirement is just 12.5%, so adding 5% makes a big difference. 

Case Studies

The City of Melrose and Town of Dedham

The city of Melrose and the town of Dedham have taken a leadership position on this model and are have run/are currently running GMA programs for their residents.

Their process:

  • They hired Good Energy, a GMA consultant.
  • The mayor and city council approved a GMA plan that Good Energy helped each city write.
  • The Mass. Department of Energy Resources, the Attorney General’s office, and the Department of Public Utilities approved the plans.
  • They each put out a request for proposals in order to find an electricity supplier. Melrose chose Constellation New Energy. Dedham chose ConEd Solutions.
  • Both GMAs launched in January 2016.

Residents' Choices:

Residents' Choices

Residents are able to opt out of the new default electricity supply into 1 of 3 options: a cheaper but browner alternative provided by the GMA, the utility’s Basic Service, or a competitive supplier’s product. They can also opt into a 100% renewable energy supply! People who were already with a competitive supplier are not automatically enrolled. Instead, they must cancel their service with the competitive supplier or await the end of their contract in order to opt into the community's GMA program.

As you can see, GMA allowed Melrose and Dedham to take hold of their resident's energy supply and provide their residents with more options.

Which communities are participating?

Massachusetts Map of Green Municipal Aggregation

The communities we feature in this section worked with Green Energy Consumers and municipal aggregation broker Good Energy to enact their GMA programs. Green Energy Consumers supplies the additional renewable energy.

If you live in one of these communities, you are probably getting more renewable energy in your electricity right now. Click on your community to learn more, and find out how you can get up to 100% renewable energy at an affordable price.

Arlington: Program launched in Aug 2017 with Good Energy.

Bedford: Program launched in Aug 2019 with Good Energy.

Brookline: Program launched in Jul 2017 with Good Energy.

DedhamProgram launched in Jan 2016 with Good Energy.

Medford: Launching in Dec 2019 with Good Energy.

MelroseProgram (round 2) launched June 2019 with Good Energy.

Gloucester: Program launched December 2018 with Good Energy.

Hamilton: Program launched December 2018 with Good Energy.

Rockland: Program launched Jul 2019 with Good Energy.

Somerville: Program Launched in Jul 2017 with Good Energy.

Stoneham: Program launched March 2019 with Good Energy.

Sudbury: Program launched in Aug 2017 with Good Energy.

Winchester: Program launched in Jul 2017 with Good Energy.

Woburn: Researching and writing aggregation plan with Good Energy.

Metropolitan Area Planning Council (MAPC) group procurement: Good Energy was the winner of a competitive procurement organized by MAPC on behalf of 101 cities and towns in eastern Massachusetts. These communities are not obligated to select Good Energy as their consultant, but the bidding process has been done for them and they can now easily begin the process of following in the footsteps of Melrose and Dedham. We expect that quite a few will be starting aggregations by 2017.

How do I get my community involved?

If you’re interested in learning more about GMA or want to find out how your community can get started, contact in MA: Eugenia Gibbons at; or in RI: Priscilla De La Cruz at, or give us a call at 800-287-3950 x5.

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