Renewable Energy Content Detail

The Commonwealth of Massachusetts requires that all electricity supply products include a minimum of 62% from renewable energy resources in 2024, 63% in 2025, and 69% in 2026. Power Choice Basic meets this minimum requirement. Power Choice Standard and Power Choice Plus exceed it.

Power Choice Plus includes the minimum amount of MA Class I RECs required by law each year plus the additional amount needed to reach 100%. Weston’s electricity supplier must also purchase other renewable energy to meet state requirements. As a result, the total renewable content for the Power Choice Plus option exceeds 100%.

Power Choice Standard

Power Choice Plus

Power Choice Basic

Eversource’s Basic Service

Renewable electricity 2024 2025 2026 2024 2025 2026 2024 2025 2026 2024 2025 2026
From new resources in the New England region (MA Class I RECs), added by Weston 20% 20% 20% 76% 73% 70%
From new resources in the New England region (MA Class I RECs), required by state law 24% 27% 30% 24% 27% 30% 24% 27% 30% 24% 27% 30%
From other clean or renewable sources, required by state law 38% 36% 39% 38% 36% 39% 38% 36% 39% 38% 36% 39%
Total from renewable sources 82% 83% 89% 138% 136% 139% 62% 63% 69% 62% 63% 69%


What are MA Class I RECs?

MA Class I RECs are renewable energy certificates (RECs) from renewable energy projects that began commercial operation after 1997, generate electricity using any of the following technologies, and meet all other program eligibility criteria:

  • Solar photovoltaic
  • Solar thermal electric
  • Wind energy
  • Small hydropower
  • Landfill methane and anaerobic digester gas
  • Marine or hydrokinetic energy
  • Geothermal energy
  • Eligible biomass fuel

Purchasing MA Class I RECs helps to create demand for more renewable energy on the New England grid. By purchasing more MA Class I RECs than is required by state law, you can help to drive the development of new renewable energy projects in our region.

What is required by Massachusetts state law?

Massachusetts state law requires all electricity suppliers include a minimum amount of electricity from renewable and clean sources, and that minimum amount increases every year. The law includes a requirement to purchase electricity from both MA Class I-eligible sources and also additional renewable / clean sources.

What are the additional renewable / clean sources referred to in the table?

The phrase “additional renewable / clean sources” refers to the renewable energy required by state law other than MA Class I RECs. Some of these sources are renewable, but not emission free, such as waste-to-energy, which is electricity generated from burning solid waste, and some of those sources are clean but not classed as renewable, such as nuclear.

How can the total renewable content exceed 100%?

Weston is committed to purchasing 100% clean, renewable energy for the additional renewable energy that it adds voluntarily in the Weston Power Choice Standard and Weston Power Choice Plus options.

Separately, Massachusetts state law requires the inclusion of a minimum amount of electricity from renewable or clean sources in all electricity that is sold, and that comes from a combination of MA Class I sources and other sources. However, while the MA Class I sources are both clean and renewable, some of the other required sources are clean but not renewable, and some are renewable but not clean.

To ensure participants in the Weston Power Choice Plus option are receiving 100% of their electricity from sources that are both renewable and clean, Weston counts only the MA Class I component of the state law requirement when deciding how much additional renewable energy to buy. To state it another way, Weston buys additional renewable energy to make up the difference between the required MA Class I amount and 100%.

Because Weston’s electricity supplier is also required to buy electricity from non-MA Class I sources, the total amount of renewable / clean energy purchased is more than 100% of the amount used by participants in Weston Power Choice Plus. By participating in Weston Power Choice Plus, you are therefore purchasing more renewable electricity than you use, but you are taking a big step toward supporting renewable energy and toward building demand for more renewable energy on our local grid.