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Ples I

Mono County, California · EIA plant ID 10479 · Operator: Ormat Nevada Inc
GeothermalGeothermalCAISOBA: CISO
Nameplate15MWSummer 10 MW
Generators3in service
Net generation75GWh12 mo to Dec 2025
Capacity factor87%geothermal units, summer MW
Heat rate—thermal plants only
First online1990

Monthly net generation

EIA-923, all units at the plant. Net of station use; storage can go negative.
FinalPreliminary
02.557.510GWh200120032006200820102012201420162018202020222024

Capacity factor by year

Net MWh ÷ (summer MW × hours), geothermal units. Each year uses that year's EIA-860 ratings; the hollow dot is the latest 12 months.
0%50%100%2005201020152020202586.9% · 12 mo

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
YearNet GWhCapacity factorHeat rate (Btu/kWh)
200197.972.1%—
200298.772.7%—
200399.573.3%—
200597.872.0%—
200692.167.8%—
20079872.2%—
2008101.674.7%—
2009103.776.4%—
2010100.874.3%—
2011107.579.1%—
2012107.879.2%—
2013100.495.5%—
201494.389.7%—
201588.784.4%—
201686.882.4%—
201796.191.4%—
201885.898.9%—
201982.495.0%—
2020103.4118.9%—
2021102.9118.7%—
202293.1107.3%—
2023104120.0%—
2024103.1118.6%—
202575.386.9%—

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 IDTechnologyPrime moverNameplate MWSummer MWOnlineStatusPlanned retirementOEM / model
T101GeothermalBT53.3Dec 1990Operating—coming soon
T102GeothermalBT53.3Dec 1990Operating—coming soon
T103GeothermalBT53.3Dec 1990Operating—coming soon

Owner / operator

Operator: Ormat Nevada Inc. Ownership shares by in-service nameplate MW (EIA-860 Schedule 4; units not listed there are wholly owned by the operator).
Mammoth Pacific LP100.0%15 MW

Nearby plants

Within 80 km.
Mammoth Pacific II15 MW0.1 km
Mammoth Pacific I10 MW0.4 km
CD444 MW0.5 km
Rush Creek13 MW23.1 km
Upper Gorge38 MW30.3 km
Middle Gorge38 MW33.6 km