Renewable energy

Renewable energy is generated by sources that can be renewed as opposed to sources that can be used only once, such as fossil fuels.

Under Massachusetts state law, a variety of resources qualify as renewable. The primary sources are solar panels, wind turbines, and small hydroelectric projects. The supply of sunlight, wind, and flowing water is not diminished when we “mine” energy from them. In addition, using electricity from renewable sources does not generate air pollution or the gases that cause climate change.

  • Sherborn Standard provides an additional 50% of your electricity from renewable sources.
  • Sherborn Select provides 100% of your electricity from renewable sources.
  • Sherborn Basic provides the minimum amount of your electricity from renewable sources required by law.

Program renewable energy content detail

Sherborn Standard Sherborn Select Sherborn Basic Eversource Basic Service
Electricity from renewable sources (% of total)*
Through May 2026 Beginning June 2026 Through May 2026 Beginning June 2026 Through May 2026 Beginning June 2026 Through May 2026 Beginning June 2026
Added by Sherborn
From wind projects outside of New England (National Wind RECs)** – 50% – 70% – – – –
From new renewable sources in the New England region (MA Class I RECs) 50% – 70% – – – – –
Required by state law
From new renewable sources in the New England region (MA Class I RECs) 30% 30% 30% 30% 30% 30% 30% 30%
Total 80% 80% 100% 100% 30% 30% 30% 30%

* In addition to purchasing the renewable energy shown in the table, the program’s electricity supplier is required by state law to purchase RECs from other clean or renewable sources. This purchase must match 39% of participants’ total electricity use.

** Beginning in June 2026, the voluntary additional renewable energy purchased through the program will be purchased from wind projects outside of New England instead of from new renewable sources within New England as in the past. This decision was made in response to changes in the renewable energy landscape. See the “Renewable Energy” section of the FAQ for more information about this change.

What does it mean to buy renewable electricity / what are RECs?

Unless you have a renewable energy system, such as solar panels, plugged directly into your home or office, you cannot purchase the specific electricity that is generated by a renewable energy project. The electricity flowing through the grid is a comingled mix of electricity generated by renewable energy projects as well as electricity generated by burning fossil fuels.

As a result, a separate accounting system has been created to keep track of renewable energy and allow it to be bought and sold. That system uses renewable energy certificates, or RECs. Every time a renewable energy project generates 1 megawatt-hour of electricity, 1 REC is minted. That REC can then be sold. Purchasing a REC gives you, and no one else, the right to say you used the electricity from that renewable energy project.

Anyone who wishes to purchase renewable electricity must then purchase 2 things (these two costs are often bundled together, which is why renewable energy costs a bit more):

  • the electricity itself from the grid
  • RECs that equal the amount of electricity they wish to claim as renewable

You can buy as many RECs as you wish

  • You can buy a small number of RECs so you can say that a part of the electricity you use is from those renewable sources.
  • You can buy enough RECs to exactly equal the amount of electricity you use, so you can say that all of the electricity you use is from those renewable sources.
  • Or you can buy RECs that equal more than the amount of electricity you use if you want to build extra demand for renewable energy.

Buying RECs provides an important source of revenue for renewable energy developers. Voluntarily buying more RECs than are required by state law signals to developers that there’s a market for more renewable energy locally and provides a motivator to build more.

Participants in both the Sherborn Standard and Sherborn Select options buy more RECs than are required by state law.