Renewable Energy Content Detail

The Commonwealth of Massachusetts requires that all electricity supply products include a minimum of 59% from renewable energy resources in 2023, including 22% from new regional renewable resources (MA Class I RECs). Westborough’s Basic plan meets this minimum requirement. Westborough’s Standard and 100% Green plans exceed it.

From new regional resources (MA Class I RECs) From other clean or renewable sources required by state law
Added by Westborough Required by state law Total MA Class I RECs
Westborough’s Standard Plan
2023 20% 22% 42% 37%
2024 20% 24% 44% 38%
2025 20% 27% 47% 36%
Westborough’s 100% Green Plan
2023 78% 22% 100% 37%
2024 76% 24% 100% 38%
2025 73% 27% 100% 36%
Westborough’s Budget Plan
2023 22% 22% 37%
2024 24% 24% 38%
2025 27% 27% 36%
 National Grid’s Basic Service
2023 22% 22% 37%
2024 24% 24% 38%
2025 27% 27% 36%


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 locally.

What are National Wind RECs?

National Wind RECs are renewable energy certificates (RECs) that come from wind projects outside of New England.

Purchasing National Wind RECs does not help to build demand for renewable energy in the New England region because these projects are based outside of New England. And because National Wind REC prices are low, purchasing these RECs has a smaller impact on the development of renewable energy projects.

However, National Wind RECs are typically less expensive than MA Class I RECs. They allow you to support renewable energy more affordably. Purchasing National Wind RECs enables you to direct your dollars to renewable sources and not to fossil-fuel-based electricity generators.

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%?

Westborough is committed to providing 100% clean, renewable energy through the 100% Green plan.

Massachusetts state law requires the inclusion of a minimum amount of electricity from renewable or clean sources in all electricity that is sold, and it 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 100% Green plan are receiving 100% of their electricity from sources that are both renewable and clean, Westborough 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, Westborough buys additional renewable energy to make up the difference between the required MA Class I amount and 100%.

Because Westborough’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 the 100% Green plan. By participating in the 100% Green plan, 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.