Stony Brook
Hampden County, Massachusetts · EIA plant ID 6081 · Operator: Massachusetts Mun Wholes Electric Co
Nameplate542MWSummer 447 MW
Generators10in service
Net generation124GWh12 mo to Aug 2026
Capacity factor3%gas/coal/oil units, summer MW
Heat rate9,267Btu/kWhfossil units, electric fuel, HHV
First online1981Runs as rarely runs
The 12-month figures include preliminary EIA-923 months, which EIA revises. Final data runs through Dec 2025.
Monthly net generation
EIA-923, all units at the plant. Net of station use; storage can go negative.
FinalPreliminary
Capacity factor by year
Net MWh ÷ (summer MW × hours), gas/coal/oil units. Each year uses that year's EIA-860 ratings; the hollow dot is the latest 12 months.
Heat rate by year
Electric fuel MMBtu × 1000 ÷ net MWh (Btu/kWh, HHV), fossil units only; CT + CA counted as one combined-cycle block.
Annual data table
| Year | Net GWh | Capacity factor | Heat rate (Btu/kWh) |
|---|---|---|---|
| 2001 | 32.2 | — | — |
| 2002 | 665.6 | — | — |
| 2003 | 576.1 | 15.1% | 9,212 |
| 2004 | 269.2 | 7.0% | 9,224 |
| 2005 | 199.6 | 5.2% | 9,596 |
| 2006 | 307 | 8.0% | 9,695 |
| 2007 | 237.9 | 6.2% | 8,490 |
| 2008 | 171 | 4.5% | 9,609 |
| 2009 | 118.7 | 3.1% | 9,715 |
| 2010 | 317.5 | 8.3% | 9,335 |
| 2011 | 152.5 | 4.0% | 9,555 |
| 2012 | 127.2 | 3.3% | 9,619 |
| 2013 | 114.6 | 3.0% | 9,766 |
| 2014 | 195.2 | 5.1% | 9,824 |
| 2015 | 216.4 | 5.6% | 9,479 |
| 2016 | 109.6 | 2.8% | 9,594 |
| 2017 | 99 | 2.6% | 9,749 |
| 2018 | 110.1 | 2.9% | 9,738 |
| 2019 | 46.3 | 1.2% | 9,914 |
| 2020 | 96.6 | 2.5% | 9,842 |
| 2021 | 54.7 | 1.4% | 9,888 |
| 2022 | 110.1 | 2.9% | 9,220 |
| 2023 | 22.1 | 0.6% | 9,942 |
| 2024 | 47.7 | 1.2% | 9,669 |
| 2025 | 104 | 2.7% | 9,998 |
Generators
EIA-860 (annual) with EIA-860M updates through Sep 2026. EIA-923 reports generation by plant, prime mover and fuel, not by unit, so unit-level output isn't shown.
| Gen ID | Technology | Prime mover | Nameplate MW | Summer MW | Online | Status | Planned retirement | OEM / model |
|---|---|---|---|---|---|---|---|---|
| 1 | Petroleum Liquids | GT | 85 | 65 | Nov 1982 | Operating | — | coming soon |
| 2 | Petroleum Liquids | GT | 85 | 65 | Nov 1982 | Operating | — | coming soon |
| 5051S | Solar Photovoltaic | PV | 6.9 | 6.9 | Jun 2018 | Operating | — | coming soon |
| BS#1 | Petroleum Liquids | IC | 2 | 2 | Sep 2007 | Operating (Standby / backup) | — | coming soon |
| BS#2 | Petroleum Liquids | IC | 2 | 2 | Sep 2007 | Operating (Standby / backup) | — | coming soon |
| CA1 | Petroleum Liquids | CA | 105 | 96 | Nov 1981 | Operating | — | coming soon |
| CT1 | Natural Gas Fired Combined Cycle | CT | 85 | 69.7 | Nov 1981 | Operating | — | coming soon |
| CT2 | Natural Gas Fired Combined Cycle | CT | 85 | 69.7 | Nov 1981 | Operating | — | coming soon |
| CT3 | Natural Gas Fired Combined Cycle | CT | 85 | 69.7 | Nov 1981 | Operating | — | coming soon |
| EDSI | Petroleum Liquids | IC | 0.6 | 0.6 | Nov 1981 | Operating | — | coming soon |
| CW1 | Petroleum Liquids | CA | 105 | 89.8 | Nov 1981 | not_current | — | coming soon |
Owner / operator
Operator: Massachusetts Mun Wholes Electric Co. Ownership shares by in-service nameplate MW (EIA-860 Schedule 4; units not listed there are wholly owned by the operator).
| Massachusetts Mun Wholes Electric Co | 90.9% | 492 MW |
| Green Mountain Power Corp | 8.7% | 47 MW |
| The Town of Lyndon Elec Dept - (VT) | 0.4% | 2 MW |
Nearby plants
Within 80 km.
| Kearsarge Ludlow LLC | 4 MW | 1.4 km |
| Ludlow Landfill | 2 MW | 1.8 km |
| Chicopee | 2 MW | 1.9 km |
| Huxley Solar | 10 MW | 2.5 km |
| Kearsarge Granby | 3 MW | 2.8 km |
| Granby Solar, LLC CSG | 5 MW | 3.4 km |