Directory of Power Plants in Massachusetts
| Plant Name | Utility | Location | Balancing Authority | Annual Generation | Plant Date | Last Update | Fuel Types |
|---|---|---|---|---|---|---|---|
| Onyx - Brockton Thatcher Landfill Solar | Onyx Asset Services Group | Brockton, MA | ISO New England (ISNE) | 5.0 GWh | Oct 2017 | Dec 2025 | Solar |
| Old Wardour Solar | NuGen Capital Management | East Brookfield, MA | ISO New England (ISNE) | 6.8 GWh | Dec 2015 | Dec 2025 | Solar |
| One Patriot | Bloom Energy | Foxborough, MA | ISO New England (ISNE) | 16.9 GWh | Nov 2019 | Dec 2025 | Natural Gas |
| Oak Bluffs Diesel Generating Facility | Vineyard Reliability LLC | Oak Bluffs, MA | ISO New England (ISNE) | 2.9 GWh | Dec 1968 | Sep 2025 | Distillate Fuel Oil |
| Orange PV | Terraform Arcadia | Orange, MA | ISO New England (ISNE) | 2.6 GWh | Jun 2013 | Dec 2025 | Solar |
| OSG Solar 1 LLC | Navisun LLC | Orange, MA | ISO New England (ISNE) | 3.1 GWh | Jun 2012 | Dec 2025 | Solar |
| Oxford | CVI CleanCapital Solar 6 | Oxford, MA | ISO New England (ISNE) | 3.1 GWh | Jun 2014 | Dec 2025 | Solar |
| Oxford Solar | Citizens Enterprises Corporation | Oxford, MA | ISO New England (ISNE) | 4.8 GWh | Jan 2020 | Dec 2025 | Solar |
| Onyx - Pembroke Landfill Solar | Onyx Asset Services Group | Pembroke, MA | ISO New England (ISNE) | 3.5 GWh | Nov 2017 | Dec 2025 | Solar |
| Oak Leaf Solar XVII Community Solar | Navisun LLC | Pittsfield, MA | ISO New England (ISNE) | 47.0 MWh | Nov 2025 | Dec 2025 | Solar |
| Oak Leaf Solar XVI Community Solar | Navisun LLC | Pittsfield, MA | ISO New England (ISNE) | 10.0 MWh | Nov 2025 | Dec 2025 | Solar |
| Old Middleboro Road Solar | Agilitas Energy, Inc. | Rochester, MA | ISO New England (ISNE) | 8.4 GWh | Dec 2022 | Dec 2025 | Solar |
| Old Frontier Solar III | Old Frontier Solar III PV, LLC | South Deerfield, MA | ISO New England (ISNE) | 3.8 GWh | Aug 2022 | Dec 2025 | Solar |
| Oak Street Solar | Citizens Enterprises Corporation | Springfield, MA | ISO New England (ISNE) | 5.4 GWh | Nov 2019 | Dec 2025 | Solar |
| Onset East Community Solar Facility | Kearsarge Onset LLC | Wareham, MA | ISO New England (ISNE) | 1.6 GWh | Mar 2016 | Dec 2025 | Solar |
| Onset West Community Solar Facility | Kearsarge Onset LLC | Wareham, MA | ISO New England (ISNE) | 1.6 GWh | Mar 2016 | Dec 2025 | Solar |
| Oakdale Power Station | Massachusetts Water Res Auth | West Boylston, MA | ISO New England (ISNE) | 1.4 GWh | Apr 1951 | Dec 2025 | Water |
| Overlook | Westbound Solar 3, LLC | Westminster, MA | ISO New England (ISNE) | 6.8 GWh | Feb 2023 | Dec 2025 | Solar |
Browse Power Plants By Massachusetts Counties
Figures are based on May 2026 generation numbers.| County | State Rank | Active Plants | May 2026 Generation |
|---|---|---|---|
| Norfolk County, MA | # 1 | 40 | 6.7 TWh |
| Worcester County, MA | # 2 | 197 | 5.4 TWh |
| Essex County, MA | # 3 | 41 | 2.5 TWh |
| Middlesex County, MA | # 4 | 68 | 1.9 TWh |
| Hampden County, MA | # 5 | 89 | 1.9 TWh |
| Plymouth County, MA | # 6 | 84 | 814.7 GWh |
| Bristol County, MA | # 7 | 74 | 645.8 GWh |
| County | State Rank | Active Plants | May 2026 Generation |
|---|---|---|---|
| Barnstable County, MA | # 8 | 25 | 628.3 GWh |
| Suffolk County, MA | # 9 | 14 | 428.0 GWh |
| Dukes County, MA | # 10 | 7 | 376.1 GWh |
| Hampshire County, MA | # 11 | 39 | 226.9 GWh |
| Berkshire County, MA | # 12 | 46 | 198.8 GWh |
| Franklin County, MA | # 13 | 33 | 182.1 GWh |