CMLP does not generate electricity; we purchase power from third part suppliers with whom we have "power purchase agreements" which specify the pricing per Kilowatt Hour (kWh) for the power we use. One of CMLP’s objectives in the area of power supply is to purchase as much energy from renewable sources as possible provided the economics are in line with more conventional power supply options.

Increasing Percentage from Non-Carbon Emitting Sources

How the Town sources electricity significantly impacts Concord’s ability to achieve its climate goals. CMLP is committed to providing 100% carbon-free electricity by 2030. Each year, CMLP is working to keep us on track. Achieving that goal will reduce greenhouse gas emissions by nearly 23% community wide.

During the last several years, CMLP has been de-carbonizing its power supply by purchasing renewable power from developers in Massachusetts, New Hampshire, Connecticut and Maine and purchasing Renewable Energy Certificates (RECs).For information about what RECs are and how they work, the U.S. Environmental Protection Agency has prepared a short video called “RECs: Making Green Power Possible” https://www.youtube.com/watch?v=_12VYXms6-c.

In 2018, the Light Plant retired a number of RECs equal to 57% of the electricity purchased in that year (58% of sales.) The 57% was made up of 8% from Massachusetts Class 1 RECs associated with energy, 3% from Maine Class 2 RECs associated with energy, 4% from Vermont Tier 1 RECs associated with the NYPA hydro generation, and 42% from the purchase of non-associated, unbundled Massachusetts Class 1 RECs. In addition to the 57% of energy for which RECs were retired, CMLP purchased electricity from the following resources that do not come with RECs: 6% from predominantly in-Town solar resources.

In 2019 the Light Plant increased the number of purchases that came with RECs from 15% to 21%. However, the price to purchase non-associated, unbundled RECs increased. CMLP was able to acquire only 33% of its purchases from non-associated, unbundled RECs in 2019, down from 42% in 2018. The Light Plant retired a number of RECs equal to 53% of the electricity purchased in that year (56% of sales.) The 53% was made up of 10% from Massachusetts Class 1 RECs associated with energy, 6% from Maine Class 2 RECs associated with energy, 5% from Vermont Tier 1 RECs associated with the NYPA hydro generation and 33% from the purchase of non-associated, unbundled Massachusetts Class 1 RECs. In addition to the 53% of energy for which RECs were retired, CMLP purchased electricity from the following resources that do not come with RECs: 6% from predominantly in-Town solar resources.

In 2020 the Light Plant increased the number of purchases that came with RECs from 21% to 24%. However, the price to purchase non-associated, unbundled RECs increased yet again compared to 2019 prices. CMLP was able to acquire only 25% of its purchases from non-associated, unbundled RECs in 2020, down from 33% in 2019. The Light Plant retired a number of RECs equal to 49% of the electricity purchased in that year (51% of sales.) The 49% was made up of 10% from Massachusetts Class 1 RECs associated with energy, 6% from Maine Class 2 RECs associated with energy, 5% from Vermont Tier 1 RECs associated with the NYPA hydro generation, 3% from Emissions-free Energy Certificates (“EFECs”) associated with nuclear-based energy and 25% from the purchase of non-associated, unbundled Massachusetts Class 1 RECs. In addition to the 49% of energy for which RECs were retired, CMLP purchased electricity from the following resources that do not come with RECs: 7% from predominantly in-Town solar resources.

In 2021, the Light Plant retired a number of RECs equal to 85% of the total amount of electricity purchased (87% of sales.) The 85% was made up of 10% from Massachusetts Class 1 RECs associated with energy, 9% from Maine Class 2 RECs associated with energy, 10% from Emissions-free Energy Certificates (“EFECs”) associated with nuclear-based energy, 4% from Vermont Tier 1 RECs associated with the NYPA hydro generation and 52% from the purchase of non-associated, unbundled Massachusetts Class 1 RECs.

In 2022, the Light Plant retired a number of RECs equal to 96% of the total amount of electricity purchased (99% of sales.) The 96% was made up of 12% from Massachusetts Class 1 RECs associated with energy, 7% from Maine Class 2 RECs associated with energy, 20% from Emissions-free Energy Certificates (“EFECs”) associated with nuclear-based energy, 4% from Vermont Tier 1 RECs associated with the NYPA hydro generation and 52% from the purchase of non-associated, unbundled Massachusetts Class 1 RECs. 2022 is the first year CMLP received MA Class I RECs donated by the Willard School and also from private residents.

With prices at their current levels, the Light Plant would be able to retire a number of RECs equal to 101% of purchases in 2023. Certificate retirements would never exceed 100%. Instead, purchases of non-associated unbundled RECs would be reduced so that the total volume of RECs retired equaled 100% of power purchases. Once that level is achieved, all of the power provided by the Light Plant will be carbon-free. The forward estimates embed assumptions about market prices, load, and generations forecasts – all of which could mean the actual figures vary, perhaps even widely, from the estimates. Vigilance needs to be maintained to ensure a carbon-free power supply into the future.

CMLP also helps customers install their own solar generation through generous grants and a favorable net metering policy. Key to achieving Concord’s climate goals and reducing community-wide emissions will be transitioning our buildings and vehicles to run off clean electricity. CMLP has programs and rebates for both. Learn more about our rebates for heat pumps and electric vehicles.

To learn more about Concord’s commitment to sustainability and climate please visit concordma.gov/sustainability.

Independent System Operators

In addition to our power purchases, we are charged for transmission of power to our Forest Ridge substation by the Independent System Operators-New England (ISO-NE). The ISO is responsible for creating and managing the wholesale market for electricity, operation of the power grid and ensuring adequate capacity in New England. While we are an independent municipal utility, we are part of the larger ISO-NE power grid.