Energy Storage

Technologies that store electricity to be used to meet demand at different times can provide significant benefits to the grid and its resiliency. Energy storage can provide backup power during outages and can help customers manage their electric load. Energy storage can also help increase the availability of renewable energy from sources like wind and solar by absorbing excess energy when it is being produced, then discharging it later when the energy is needed.

Learn more about energy storage from the U.S. Department of Energy.

Maine's Energy Storage Goals

In June 2021, Governor Mills signed Public Law 2021 Chapter 298 (LD 528 - An Act To Advance Energy Storage in Maine, or "the Act"). The Act sets goals for energy storage in Maine and directs multiple important steps to advance its deployment to the benefit of Maine.

The State of Maine has established in statute the following goals for energy storage capacity installed within the state:

  • 300 megawatts by 2025
  • 400 megawatts by 2030

A goal of 400 megawatts of energy storage represents about 20% of Maine’s peak electric demand in 2020, making these goals some of the most ambitious in the nation. As of 2021 there are about 50 megawatts of energy storage operating in the state.

The legislation also requires the Governor’s Energy Office is required to update the state’s energy storage goals beginning in 2031 as needed to align with Maine’s emissions reduction and renewable portfolio standard requirements.

The Governor’s Energy Office is also required to conduct a study, including opportunities for stakeholder input, to inform the achievement of the state’s energy storage goals and related policy objectives. More information about this study will be announced soon.

Energy Storage for Maine homes and businesses

The Act directs the Efficiency Maine Trust to incorporate energy storage technologies into its electric efficiency and conservation program offerings. To learn more as these programs develop, visit the Efficiency Maine Trust website.

The Act also directs the Efficiency Maine Trust to establish a specific pilot program to deploy energy storage for hospitals, fire departments, emergency medical services, police and public safety buildings, emergency shelters, and other facilities providing critical care facilities. This pilot program will contribute to the important effort of increasing resiliency, ensuring communities have the energy resources needed to withstand weather-related or other emergency outages made even more serious by climate change.

Efficiency Maine Trust also manages Innovation Pilot Programs that may include energy storage technologies.

Energy Storage in Maine's electricity markets

Energy storage is allowed to participate in the renewable energy procurements signed into law in June 2019 and June 2021. More information can be found at the Public Utilities Commission.

The Public Utilities Commission was also directed by the Act to study rate design changes that can enhance the value of energy storage, and to evaluate the feasibility of a power-to-fuel pilot program.

Energy Storage Commission

The 129th Maine Legislature established the Commission to Study the Economic, Environmental and Energy Benefits of Energy Storage to the Maine Electricity Industry with the passage of Resolve 2019, chapter 83. This Commission met in 2019 and produced a final report that can be found here.