RE Tranquillity
Fresno County, California · EIA plant ID 59939 · Operator: Southern Power Co
Nameplate277MWSummer 272 MW
Generators3in service
Net generation485GWh12 mo to Dec 2025
Capacity factor28%solar units, summer MW
Heat rate—thermal plants only
First online2016
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), solar 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) |
|---|---|---|---|
| 2016 | 207.8 | 23.5% | — |
| 2017 | 455.4 | 26.0% | — |
| 2018 | 501.8 | 28.6% | — |
| 2019 | 493.4 | 28.2% | — |
| 2020 | 428.1 | 24.4% | — |
| 2021 | 486.6 | 27.8% | — |
| 2022 | 424.9 | 24.8% | — |
| 2023 | 450.4 | 26.2% | — |
| 2024 | 491.4 | 28.6% | — |
| 2025 | 484.8 | 28.3% | — |
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 |
|---|---|---|---|---|---|---|---|---|
| BESS1 | Batteries | BA | 37 | 37 | Nov 2021 | Operating | — | coming soon |
| BESS2 | Batteries | BA | 35 | 35 | Mar 2022 | Operating | — | coming soon |
| TQ | Solar Photovoltaic | PV | 205.3 | 200 | Jul 2016 | Operating | — | coming soon |
Owner / operator
Operator: Southern Power Co. Ownership shares by in-service nameplate MW (EIA-860 Schedule 4; units not listed there are wholly owned by the operator).
| RE Tranquillity LLC | 74.0% | 205 MW |
| SP Tranquillity Solar Storage, LLC | 26.0% | 72 MW |
Nearby plants
Within 80 km.
| Luna Valley | 200 MW | 1.2 km |
| Great Valley Solar Portfolio Holdings, LLC | 203 MW | 2.2 km |
| Scarlet II Hybrid | 350 MW | 3.6 km |
| Scarlet Solar (CA) | 240 MW | 4.2 km |
| EDPR CA Solar Park VI LLC (CA) Hybrid | — | 5.4 km |
| EDPR Scarlet III | — | 5.7 km |