Seabrook
Rockingham County, New Hampshire · EIA plant ID 6115 · Operator: NextEra Energy Seabrook LLC
Nameplate1,242MWSummer 1,247 MW
Generators1in service
Net generation9,882GWh12 mo to Aug 2026
Capacity factor90%nuclear units, summer MW
Heat rate—thermal plants only
First online1990
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), nuclear 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.
Heat rate applies to fuel-burning (thermal) units only.
Annual data table
| Year | Net GWh | Capacity factor | Heat rate (Btu/kWh) |
|---|---|---|---|
| 2001 | 8,692.7 | 85.5% | — |
| 2002 | 9,294.6 | 91.4% | — |
| 2003 | 9,276.3 | 91.3% | — |
| 2004 | 10,177.6 | 99.9% | — |
| 2005 | 9,455.9 | 88.5% | — |
| 2006 | 9,397.9 | 86.2% | — |
| 2007 | 10,763.9 | 98.7% | — |
| 2008 | 9,350.3 | 85.5% | — |
| 2009 | 8,816.7 | 80.7% | — |
| 2010 | 10,910.1 | 99.9% | — |
| 2011 | 8,362.8 | 76.6% | — |
| 2012 | 8,189.2 | 74.8% | — |
| 2013 | 10,926.7 | 100.1% | — |
| 2014 | 10,168.3 | 93.1% | — |
| 2015 | 9,484.2 | 86.8% | — |
| 2016 | 10,761.2 | 97.9% | — |
| 2017 | 9,990.7 | 91.3% | — |
| 2018 | 10,061.7 | 91.8% | — |
| 2019 | 10,906.9 | 99.6% | — |
| 2020 | 9,865.2 | 90.0% | — |
| 2021 | 9,856.1 | 90.1% | — |
| 2022 | 10,921.5 | 99.9% | — |
| 2023 | 9,534.8 | 87.4% | — |
| 2024 | 9,676.9 | 88.1% | — |
| 2025 | 10,910.2 | 99.9% | — |
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 | Nuclear | ST | 1,242 | 1,247 | Aug 1990 | Operating | — | coming soon |
Owner / operator
Operator: NextEra Energy Seabrook LLC. Ownership shares by in-service nameplate MW (EIA-860 Schedule 4; units not listed there are wholly owned by the operator).
| NextEra Energy Seabrook LLC | 88.2% | 1,096 MW |
| Massachusetts Mun Wholes Electric Co | 11.6% | 144 MW |
| City of Taunton - (MA) | 0.1% | 1 MW |
| Town of Hudson - (MA) | 0.1% | 1 MW |
Nearby plants
Within 80 km.
| Hampton Facility | 5 MW | 4.4 km |
| True North | 5 MW | 7 km |
| Kearsarge Amesbury Hybrid | 5 MW | 10 km |
| Hunt Road Solar | 5 MW | 11.9 km |
| Bashaw Solar CSG 1, LLC | 2 MW | 12.5 km |
| Merrimac Solar | 2 MW | 13.8 km |