Marion County Solar Project
Marion County, Ohio · EIA plant ID 66860 · Operator: Marion County Solar Project, LLC
Nameplate100MWSummer 100 MW
Generators1in service
Net generation115GWh12 mo to Aug 2026
Capacity factor26%solar units, summer MW
Heat rate—thermal plants only
First online2026
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), 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.
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 |
|---|---|---|---|---|---|---|---|---|
| USMNC | Solar Photovoltaic | PV | 100 | 100 | Mar 2026 | Operating | — | coming soon |
Owner / operator
Operator: Marion County Solar Project, LLC. Ownership shares by in-service nameplate MW (EIA-860 Schedule 4; units not listed there are wholly owned by the operator).
| Marion County Solar Project, LLC | 100.0% | 100 MW |
Nearby plants
Within 80 km.
| POET Biorefining - Marion, LLC | 8 MW | 1.8 km |
| Whirlpool Corporation - Marion Wind Farm | 5 MW | 5.2 km |
| Harpster Wind | 2 MW | 13 km |
| Prospect Municipal | 2 MW | 20.9 km |
| Galion Generating Station | 50 MW | 31 km |
| Galion | 5 MW | 31.2 km |