Kleen Energy Systems Project
Middlesex County, Connecticut · EIA plant ID 56798 · Operator: Kleen Energy Systems, LLC
Nameplate693MWSummer 622 MW
Generators3in service
Net generation3,894GWh12 mo to Aug 2026
Capacity factor71%gas/coal/oil units, summer MW
Heat rate7,143Btu/kWhfossil units, electric fuel, HHV
First online2011Runs as baseload
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) |
|---|---|---|---|
| 2011 | 1,924.5 | 69.4% | 6,899 |
| 2012 | 4,063 | 74.4% | 7,167 |
| 2013 | 3,242.7 | 59.5% | 7,145 |
| 2014 | 3,323.2 | 61.0% | 7,111 |
| 2015 | 4,370.3 | 80.2% | 7,091 |
| 2016 | 4,005.8 | 73.3% | 7,070 |
| 2017 | 3,984.8 | 73.1% | 7,110 |
| 2018 | 2,579.6 | 47.3% | 7,250 |
| 2019 | 2,115.4 | 38.8% | 7,279 |
| 2020 | 1,766.4 | 32.3% | 7,273 |
| 2021 | 2,418.3 | 44.4% | 7,166 |
| 2022 | 2,416.2 | 44.3% | 7,143 |
| 2023 | 2,700.1 | 49.5% | 7,118 |
| 2024 | 2,912.5 | 53.3% | 7,075 |
| 2025 | 3,216.2 | 59.0% | 7,131 |
Fuel capability
Gas-fired turbines (CT/GT/CA/CS) that can also burn liquid fuel. EIA-860 Schedule 3 for capability, EIA-923 for actual burn.
StatusLikely still dual fuel
Liquid fuel burned · 36 mo859,992 MMBtu
Last month with liquid burnFeb 2026
Switch while operatingYes
Net summer MW on gas353
Net summer MW on oil326
Time gas → oilup to 6 h (EIA 6H)
Time oil → gasup to 6 h (EIA 6H)
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 |
|---|---|---|---|---|---|---|---|---|
| ST | Natural Gas Fired Combined Cycle | CA | 295 | 268 | Jul 2011 | Operating | — | coming soon |
| U1 | Natural Gas Fired Combined Cycle | CT | 199 | 177 | Jul 2011 | Operating | — | coming soon |
| U2 | Natural Gas Fired Combined Cycle | CT | 199 | 177 | Jul 2011 | Operating | — | coming soon |
Owner / operator
Operator: Kleen Energy Systems, LLC. Ownership shares by in-service nameplate MW (EIA-860 Schedule 4; units not listed there are wholly owned by the operator).
| Kleen Energy Systems, LLC | 100.0% | 693 MW |
Nearby plants
Within 80 km.
| Middletown | 786 MW | 1.5 km |
| Elevate Middletown | — | 1.5 km |
| GenConn Middletown LLC | 242 MW | 1.7 km |
| CJTS Energy Center | retired | 2.3 km |
| Wesleyan University Cogen 1 | 2 MW | 4.8 km |
| CP Middletown Solar I LLC | 1 MW | 9.2 km |