Next Steps for Massachusetts Peaker Power Plants
August 7, 2026
In March 2024, the Healey-Driscoll Administration established the nation’s first Office of Energy Transformation (OET)[1], accelerating the energy transformation required for the Commonwealth to reach its 2050 climate targets. An Advisory Board (ETAB) and three working groups were established with clear workplans and timelines: Financing the Transition (FTT); Decarbonizing the Peak (DTP); and Everett Marine Terminal (EMT). A fourth was added later, Enabling Sustainable Economic Development. The DTP Working Group focused on decarbonizing how we meet peak electric demand by showing pathways to reducing reliance on and eliminating fossil fuels from peaking power plants and deploying alternative demand and supply options to meet peak load needs. Findings and recommendations from the DTP, FTT, and EMT Working Groups were presented at the ETAB meeting in June 2026. This blogpost summarizes some useful information about peaker plants including what they are and why they are used, why they are important to decarbonization, what fuels they use, where they are in Massachusetts, why the DTP was set up, the DTP preliminary recommendations, and next steps.
What are peaker plants, and why are they used?
Peaker power plants enable grid reliability by supplying energy at “peak” times – during periods of high electricity demand when the electric grid is stressed. Peaks vary depending on weather, time of year, and consumer behavior. Currently, peak demand in New England occurs during the summer when more electricity is used to cool buildings, but by 2050, peak demand is expected to shift to winter mornings and evenings with a longer duration and more demand than the current peak[2].
Peaker plants are more expensive to run and less efficient than other types of plants. They are designed to turn on and off quickly, and are used infrequently, in times of grid stress or for daily peaks. Because of the nature of their usage, peaker plants often run in the background. This makes them highly inefficient and causes them to emit disproportionate amounts relative to the energy they provide. A US Government Accountability Office study indicated that peaker plants are less efficient than other power plants, due to their continual, fuel-intensive start-up and shut-down periods[3].
Why are peaker plants important for decarbonization?
The shift from fossil to renewable-powered peaker plants is imperative for achieving Massachusetts’ 2050 net-zero climate target. As peakers are inefficient, their transition to clean energy offers a unique opportunity for decarbonization. In some cases, existing infrastructure can be used to avoid the emissions and capital-intensive process of construction. Potential alternative energy sources include renewables like wind and solar, battery storage, and measures to reduce consumer demand for energy. Some of these can be combined for maximum efficiency. For example, solar and wind offer intermittent energy generation but when combined with battery storage, grid operators can pull from stored energy when solar and wind are not available, as opposed to firing up a fossil-powered peaker plant. This is especially relevant when considering changing peak demands due to climate change and electrification. Decarbonization is further supported by the Massachusetts Clean Peak Standard initiative, providing financial support for technologies that decrease demand or generate clean energy during energy peaks[4].
What fuels do peaker plants use?
About 97% of peaker plants are powered using natural gas or oil[5]. They provide 15% of ISO-NE’s grid capacity, but only account for a small percentage of energy generation[6]. In 2022, they contributed 10% of Massachusetts’ total greenhouse gas emissions[7]. Some plants in Massachusetts have begun to, or are planning to, transition to renewable energy peakers. For example, the West Springfield Generation Station was retired in 2022 and is currently being converted to a 45-megawatt battery storage facility[8]. There has also been significant local political pressure to redevelop the Pittsfield Generating Co. Plant, which is nearing the end of its useful life within the next five years. The plant, like other peakers, is harmful to the nearby community, and could be redeveloped into a battery energy storage facility. However, there is no economic incentive for the plant to transition to clean energy, and, unlike West Springfield, it does not have the proper grid infrastructure to smoothly carry it out[9].
Where are peaker plants located in Massachusetts?
There are 25 peaker plants in the state of Massachusetts (see Figure 1), located in Sandwich, Salem, Ludlow, Medway, Springfield, Milford, Braintree, Dighton, Pittsfield, Medway, Fall River, Dartmouth, Lowell, Boston, Peabody (2), Framingham, Marlborough, Shrewsbury, Taunton, Chicopee, Oak Bluffs, West Tisbury, Marblehead, and Worcester[10]. Fossil fuel peaker plants are disproportionately located in environmental justice (EJ) communities, making them more likely to face public health risks by exposing residents to local pollutants such as sulfur dioxide, nitrogen oxides, small particulates, and mercury.
Figure 1: Relative Size and Location of Peaker Plants in Massachusetts
Source: Decarbonizing the Peak Focus Area Working Group Summary of Working Group Status, June 2025, p.8, https://www.mass.gov/doc/summary-of-working-group-status-decarbonizing-the-peak-focus-area-working-group/download
Why was the Decarbonizing the Peak Working Group set up?
The Decarbonizing the Peak (DTP) Working Group was created in July 2024 to promote collaboration between stakeholders and advise the Massachusetts Office of Energy Transformation Advisory Board (ETAB) on decarbonizing peaker plants.
What work has the Working Group undertaken?
The work of the DTP Working Group has been split into three phases: Phase 1) Assessing the current role of peaker plants and CHP; Phase 2) Assessing alternatives to fossil fuel; and Phase 3) recommendations and implementation. The group has completed Phases 1 and 2 and is finalizing Phase 3. In Phase 1, the group gathered baseline technical information that was then used to create a screening framework to assess alternatives. In Phase 2, they ruled out alternatives that would not work in Massachusetts and analyzed the more fitting supply- and demand-side alternatives. In Phase 3, the group is synthesizing their findings from Phase 1 and Phase 2 into recommendations. The report link, including these findings, will be updated here once finalized.
What are the Working Group’s Findings?
The following eleven findings summarize Phase 1 and Phase 2 results, providing a foundation for future policy recommendations:
- Finding 1: The reliability challenge is expected to shift from short-duration summer peaks (2030) to longer sustained morning and evening winter peaks by the 2040s, driven by heating electrification and periods of low renewable output.
- Finding 2: Peaking plants are expected to continue to operate infrequently but remain critical for reliability until alternatives with equivalent capacity contributions can be deployed feasibly, safely, and cost-effectively at scale.
- Finding 3: Targeted load management and demand response during net peak periods can play an important role in 2030 and is expected to remain valuable through 2050, though its effectiveness during longer winter net peak periods is uncertain, and may drive innovation in demand-side solutions.
- Finding 4: Peak electricity resources are financed in a way that supports structures that can perform reliably during times of grid stress. ISO-NE is currently engaged in a process to ensure that all resources are valued based on their reliability contribution, including clean resources such as wind, solar, and demand response.
- Finding 5: In the short-term (2030), technology and fuel options to reduce reliance on fossil fuel-powered peaking plants include a range of short- and long-duration energy storage technologies, renewables, demand-side solutions, grid-enhancing technologies, and, potentially, alternative fuels that can be procured and operational within this timeframe.
- Finding 6: In the mid-term (2040), increased deployment of renewable generation, particularly on-shore and off-shore wind that generates power during winter net peak periods, will need to be paired with additional storage capacity to support the grid’s resource adequacy needs.
- Finding 7: An analysis indicates that aggressive deployment of demand side measures, energy storage, solar, onshore and offshore wind generation, hydropower, and other clean energy options paired with firm, dispatchable clean resources and grid optimization could allow for complete decarbonization of the grid using all non-combustion resources by 2050.
- Finding 8: Given the many services provided by institutional Combined Heat and Power (CHP) plants, decarbonization and eventual replacement will require a portfolio approach.
- Finding 9: Community engagement and equity are essential elements of any policy and action addressing the energy transition, particularly to ensure that communities disproportionately burdened by existing energy infrastructure are not further exposed to cumulative health and environmental harms, that decarbonization efforts deliver tangible local health and environmental benefits, and that the state is supporting a just workforce transition.
- Finding 10: The interconnection process currently poses a significant barrier to developing new resources that would displace or reduce reliance on peaking plants.
- Finding 11: Decarbonization pathways for specific peaking plant sites will depend on multiple general and site-specific factors.
Next Steps:
At the June 2026 meeting of the ETAB the findings and preliminary recommendations from the DTP were discussed. ETAB affirmed the findings and asked the DTP to move forward with finalizing the policy recommendations. They also approved a proposal to sunset the FTT, EMT, and DTP Working Groups by October 2026 after the final reports and recommendations are released. At the same time, a new Working Group, the Peak Energy Demand Reduction (PEDR) Working Group, was launched with an informational webinar on July 20, 2026. This Working Group will focus on identifying and prioritizing the most impactful strategies for reducing system-wide peak gas and electric demand and reducing locationally specific peak energy demand growth that would otherwise require electric infrastructure buildout and/or the need to maintain local distribution company contracting with the Everett Marine Terminal.
[1] Executive Office of Energy and Environmental Affairs, "Healey-Driscoll Administration Establishes Nation’s First Office of Energy Transformation," press release, March 15, 2024, https://www.mass.gov/news/healey-driscoll-administration-establishes-nations-first-office-of-energy-transformation.
[2] Mireille Bejjani et al., Decarbonizing the Peak: A Roadmap for Retiring and Replacing Massachusetts’ Fossil Fuel Peaker Plants by 2050, Massachusetts Clean Peak Coalition, February 2026, 5, https://www.cleanegroup.org/wp-content/uploads/Decarbonizing-the-Peak-Report.pdf.
[3] U.S. Government Accountability Office, Electricity: Information on Peak Demand Power Plants, May 21, 2024, 1, https://www.gao.gov/assets/gao-24-106145.pdf.
[4] Bejjani et al., Decarbonizing the Peak, 8.
[5] GAO, Electricity: Information on Peak Demand Power Plants, Table 1, p. 2.
[6] Massachusetts Office of Energy Transformation, Decarbonizing the Peak: Background, October 2024, 2, https://www.mass.gov/doc/decarbonizing-the-peak-background/download.
[7] Massachusetts Office of Energy Transformation, Decarbonizing the Peak: Background, October 2024, 4, https://www.mass.gov/doc/decarbonizing-the-peak-background/download.
[8] Bejjani et al., Decarbonizing the Peak, 9.
[9] Bejjani et al., Decarbonizing the Peak, 11.
[10] Massachusetts Office of Energy Transformation, Decarbonizing the Peak Focus Area Working Group Summary of Working Group Status, June 2025, Table 1, p. 7-8, https://www.mass.gov/doc/summary-of-working-group-status-decarbonizing-the-peak-focus-area-working-group/download.
