STONY BROOK
OperatingNatural Gas power plant
- Capacity
- 535 MW
- Primary fuel
- Natural Gas
- County
- Hampden County
- Operator
- MASSACHUSETTS MUN WHOLES ELECTRIC CO
- Status
- Operating
- Commissioned
- 1981
- EIA plant ID
- 6081
- Generators
- 10
- Net generation (2024)
- 47.7 GWh
- Capacity factor (2024, EIA nameplate)
- 1%
- Data vintage
- EIA-860 2024 final; EIA-923 2022-2024 final
- Coordinates
- 42.1978, -72.5106
STONY BROOK, a 535 MW Natural Gas power plant in Hampden County, Massachusetts. Operated by MASSACHUSETTS MUN WHOLES ELECTRIC CO, commissioned 1981.
How STONY BROOK compares
With 535 MW of capacity, STONY BROOK ranks 7th among the 125 operating power plants Bywatts maps in Massachusetts and 4th of the 22 operating Natural Gas plants in the state. It accounts for about 10% of Massachusetts's operating Natural Gas capacity and 5.8% of all operating capacity in the state. Nationally it is the 313th-largest of the 1,185 operating Natural Gas plants in the database. Commissioned in 1981, it is older than 63% of the 122 operating Massachusetts plants with a recorded commissioning year. Its operator, MASSACHUSETTS MUN WHOLES ELECTRIC CO, runs 2 operating plants in Massachusetts totaling 550 MW. It shares Hampden County with 19 other operating plants, including BERKSHIRE POWER and MASSPOWER.
Under the same EIA plant code, EIA-860 lists 10 generators at the site with 542 MW of nameplate capacity. Net generation was 47.7 GWh in 2024 (a 1% capacity factor). Its generators came online between 1981 and 2018.
Grid neighborhood
The nearest named substation is SCITICO, about 15.1 miles away; the closest transmission line found within 10 miles is a 345 kV line, under 0.1 miles away. Another 26 operating power plants totaling 768 MW sit within 25 miles; the largest is BERKSHIRE POWER (289 MW, Natural Gas).
Computed by Bywatts from HIFLD power plant, substation and transmission line records and EIA-860/923 survey data; distances are straight-line. Sources and methodology
Weather peril exposure
STONY BROOK is a 535 MW natural gas power plant in Hampden County, MA, operated by MASSACHUSETTS MUN WHOLES ELECTRIC CO, commissioned in 1981. Hampden County carries low modeled catastrophe exposure in the FEMA National Risk Index, scoring 1.6 of 5 at the 14th national percentile. Hurricane is the leading peril, rated Relatively High by FEMA at the 80th percentile.
The Bywatts loss layer is calibrated to solar PV hardware, so it is not applied to a natural gas plant. The ratings below are the FEMA National Risk Index county hazard ratings for this location.
Hampden County hazard ratings
| Peril | FEMA rating | National percentile | Peril score | Events per year |
|---|---|---|---|---|
| Hurricane | Relatively High | 80th | 4.2 of 5 | 0.11 |
| Ice storm | Relatively High | 68th | 3.7 of 5 | 2.3 |
| Earthquake | Relatively Moderate | 63rd | 3.5 of 5 | <0.01 |
| Riverine flooding | Relatively High | 60th | 3.4 of 5 | 2.8 |
| Winter weather | Relatively Moderate | 39th | 2.5 of 5 | 17.5 |
| Tornado | Relatively Moderate | 29th | 2.2 of 5 | 0.19 |
| Wildfire | Very Low | 21st | 1.8 of 5 | <0.01 |
| Strong wind | Relatively High | 15th | 1.6 of 5 | 1.8 |
| Hail | Relatively Moderate | 14th | 1.6 of 5 | 2.9 |
| Lightning | Relatively Moderate | 11th | 1.4 of 5 | 26.5 |
| Heat wave | Relatively Moderate | 7th | 1.3 of 5 | 5.1 |
Perils not assessed in Hampden County
These perils carry no usable National Risk Index figure for this county, so they are excluded from the scoring rather than scored zero. A zero would claim the peril was assessed and found benign.
| Peril | Why it is not scored |
|---|---|
| Coastal flooding | FEMA rating is "Not Applicable" for this county |
Model hail, wind and flood exposure for Hampden County in the weather risk calculator
Ratings are the FEMA National Risk Index county hazard ratings; the peril score is a Bywatts transform of the FEMA national percentile. Full data sources and the solar vulnerability methodology are in the weather risk calculator.
Modeled estimate for screening and negotiation. Built from FEMA National Risk Index county hazard data and a solar vulnerability layer documented above. Not a quote, a binder, or actuarial advice, and not a substitute for a carrier's own model. Hazard data: FEMA National Risk Index December 2025, synced 2026-07-24. Resolution is county level, not site level.