Electricity aggregation and community sustainability

The Green Worcester ElectriCITY Municipal Aggregation Program is helping the City to take a big step toward its sustainability goals. Through the program, the City is increasing the amount of energy generated by renewable sources in the City’s electricity supply. Purchasing electricity generated from renewable sources like the sun and the wind instead of electricity generated by burning fossil fuels is important because it does not pollute the air and does not create the greenhouse gases that cause climate change.

  • New participants are automatically enrolled in the Standard Green option, which more than doubles the amount of electricity from new renewable resources in the New England region (MA Class I RECs) participants receive.
  • Participants can also choose the 100% Green option to receive all of their electricity from new renewable resources in the New England region (MA Class I RECs).

What is renewable energy?

Renewable energy is energy 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 main sources of renewable energy are solar, wind, and small hydroelectric projects.

Not all renewable energy is the same

Worcester prioritizes buying renewable energy from New England-based renewable energy projects.

  • More renewable energy added to the local grid. Buying renewable energy from New England strengthens demand for the electricity generated by those projects. This helps to stimulate the development of more renewable energy projects in New England.
  • Stronger local businesses and local jobs. Purchasing renewable energy from New England-based renewable energy projects means supporting New England-based businesses and the jobs they provide to local communities.


Opt up to Worcester 100% Green!

The program offers the option for you to choose 100% renewable electricity with the Worcester 100% Green option for a small premium. If you opt up to Worcester 100% Green, all of the electricity you use will be generated from renewable sources like the sun and the wind, using renewable energy projects in the New England region. By choosing the Worcester 100% Green option, you make an even greater commitment to sustainability and to supporting renewable energy on our local power grid.

Opt up to Worcester 100% Green

What it means to “buy renewable energy”

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 mix, and it includes electricity generated by renewable energy projects as well as electricity generated by fossil fuels, such as coal, oil, and gas, and other resources, such as nuclear. The individual sources cannot be separated out at the level of the grid.

As a result, a separate system has been created to keep track of renewable energy and to 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 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: they must purchase the electricity itself from the grid, and then they must also purchase RECs for a percentage of electricity usage that they want to claim as green. (These two costs are often bundled together, and they are why renewable energy costs a bit more.) Those RECs are then retired so that they cannot be purchased by anyone else, and no one else can claim to have used that renewable electricity.

The Green Worcester ElectriCITY Municipal Aggregation Program is purchasing RECs in order to integrate an increased amount of renewable energy into the City’s electricity supply. No one else will be able to claim the energy associated with the RECs that Worcester buys.

The minimum amount of renewable energy required by state law

Massachusetts state law requires that all electricity sold in the state must include a minimum amount of electricity generated by renewable sources. These requirements are known as the Renewable Portfolio Standard (RPS). The required amounts of renewable energy from the New England region increase a little every year.

Electricity from new regional resources in the New England region (MA Class I RECs):

  • 22% in 2023
  • 24% in 2024
  • 27% in 2025

Electricity from other renewable or clean sources in the New England region:

  • 37% in 2023
  • 38% in 2024
  • 36% in 2025

The Green Worcester ElectriCITY Municipal Aggregation Program purchases additional renewable energy, over and above the renewable energy required to meet state requirements, for both the Standard Green and the 100% Green program options.