How aggregation works

Municipal electricity aggregation is a form of group electricity purchasing. Electricity aggregation replaces your electricity supplier, and it changes the price that Eversource uses to calculate the supply services charge piece of your electricity bill. In addition, aggregation can increase the amount of renewable energy in your electricity supply. But electricity aggregation does not replace Eversource as your electric utility.

Here’s how it works:

Without the Greenfield Light & Power program

(Unless you already have a contract with an electricity supplier)

Typically, Eversource provides two services to you as an electricity customer, and your electricity bill includes charges for both of these services:

Electricity delivery

Eversource’s primary role is as an electricity delivery company. They deliver electricity to you, maintain the poles and wires, and address power outages. They charge you for these services on the delivery part of your Eversource electricity bill.

Electricity supply

For most people, Eversource also provides a second service, which is as an electricity supplier. They purchase electricity on your behalf and charge you on the supply part of your Eversource electricity bill for the amount you use. When Eversource is your electricity supplier, you have Eversource’s Basic Service. When you first open your electricity account, you are placed on Eversource’s Basic Service.

The diagram below shows Eversource both delivering and supplying electricity.

Diagram of Eversource delivering and supplying electricity

Eversource’s fixed Basic Service prices change seasonally, every 6 months for residential and commercial customers and every 3 months for industrial customers, and future prices are not known.

With Greenfield Light & Power

In an electricity aggregation like Greenfield Light & Power, Eversource continues to deliver your electricity and you continue to call them when the power goes out, but you no longer have Eversource’s Basic Service for the supply portion of your electricity bill.  Instead, the City of Greenfield uses the bulk purchasing power of the community to negotiate a contract with an electricity supplier on behalf of residents and businesses and to determine the price of the community’s electricity supply and whether any additional renewable electricity is included. If you participate in Greenfield Light & Power, Eversource uses the Greenfield Light & Power price to calculate the supply services portion of your electricity bill instead of their own Basic Service price.

Diagram of an electricity supplier, Eversource, and the City of Greenfield


The Greenfield Light & Power price is a fixed long-term price that does not change seasonally.

What changes with the program

If you participate, you will see two changes on your Eversource electricity bill beginning the month after you enroll:

  1. Greenfield’s electricity supplier, Direct Energy, will be listed on your bill as your electricity supplier through your January 2021 bill. Then Dynegy will be listed on your bill beginning in February 2021.
  2. Eversource will use the Greenfield Light & Power price to calculate the supply charge portion of your electricity bill instead of their own Basic Service price.

See an example Eversource bill.

Otherwise, your primary relationship for electricity will remain with Eversource. This means:

  • You will continue to receive one bill from Eversource. This is the only electricity bill you will receive as a participant in Greenfield Light & Power.
  • You will continue to call Greenfield if your power goes out. Greenfield will continue to deliver electricity, restore electricity service after a power outage, and maintain the poles and wires.
  • If you receive net metering credits from solar panels on your Greenfield bill, those will continue to be calculated using Eversource’s Basic Service price, not using the Greenfield Light & Power price.
  • If you are eligible for a low-income discount, you will continue to receive that discount.

Participating in the program

All new electricity customers in Greenfield will be automatically enrolled in Greenfield Light & Power within a few months of opening the account. Automatic enrollment is state law.

You will receive a notification in mail from Greenfield before being automatically enrolled with information about the program. If you do not wish to participate, you may opt out before being automatically enrolled or any time after enrollment, with no penalty. If you choose to opt out, Eversource will continue to be your electricity supplier, and Eversource will use their own Basic Service price to calculate the supply services portion of your electricity bill.

Learn how to enroll if you will not be automatically enrolled.