Millennium Power
Worcester County, Massachusetts · EIA plant ID 55079 · Operator: Millennium Power Partners LP
Nameplate428MWSummer 330 MW
Generators2in service
Net generation908GWh12 mo to Aug 2026
Capacity factor31%gas/coal/oil units, summer MW
Heat rate7,508Btu/kWhfossil units, electric fuel, HHV
First online2001Runs as intermediate
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 | 1,063.1 | — | — |
| 2002 | 2,471.2 | — | — |
| 2003 | 1,457.4 | 49.3% | 7,168 |
| 2004 | 1,057.7 | 35.6% | 7,158 |
| 2005 | 1,459.5 | 51.1% | 7,218 |
| 2006 | 1,569.4 | 55.1% | 7,176 |
| 2007 | 1,937.8 | 68.0% | 7,176 |
| 2008 | 1,937.7 | 67.8% | 7,151 |
| 2009 | 2,003.2 | 70.3% | 7,168 |
| 2010 | 2,033.3 | 71.4% | 7,162 |
| 2011 | 2,407.2 | 84.5% | 7,222 |
| 2012 | 2,002.9 | 68.1% | 7,278 |
| 2013 | 1,484.5 | 50.6% | 7,269 |
| 2014 | 1,828 | 62.3% | 7,252 |
| 2015 | 2,101.4 | 71.6% | 7,176 |
| 2016 | 1,783.2 | 60.6% | 7,219 |
| 2017 | 1,320 | 45.0% | 7,265 |
| 2018 | 1,118.8 | 38.1% | 7,219 |
| 2019 | 902.8 | 30.8% | 7,329 |
| 2020 | 1,046.7 | 35.6% | 7,303 |
| 2021 | 691.8 | 23.9% | 7,311 |
| 2022 | 1,152.6 | 39.8% | 7,254 |
| 2023 | 625.5 | 21.6% | 7,365 |
| 2024 | 520.6 | 17.9% | 7,498 |
| 2025 | 852.2 | 29.5% | 7,495 |
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 |
|---|---|---|---|---|---|---|---|---|
| CT01 | Natural Gas Fired Combined Cycle | CT | 295.2 | 222.1 | Apr 2001 | Operating | — | coming soon |
| ST01 | Natural Gas Fired Combined Cycle | CA | 132.3 | 108 | Apr 2001 | Operating | — | coming soon |
Owner / operator
Operator: Millennium Power Partners LP. Ownership shares by in-service nameplate MW (EIA-860 Schedule 4; units not listed there are wholly owned by the operator).
| Millennium Power Partners LP | 100.0% | 428 MW |
Nearby plants
Within 80 km.
| Incom Solar, LLC CSG | 2 MW | 0.5 km |
| Southbridge Landfill Gas-to-Energy | 2 MW | 1.7 km |
| Farley Road Community Solar | 2 MW | 1.8 km |
| Sampson Road Community Solar | 2 MW | 1.8 km |
| Charlton Solar I CSG | 4 MW | 2.3 km |
| Southbridge Solar | 2 MW | 2.4 km |