W R Gianelli

W R Gianelli is a 424 MW pumped storage hydro plant in Merced County, California, operated by California Dept. of Water Resources. EIA-860M lists 8 generating units here, inside CAISO. Its units entered service between 1967 and 1968.

As of 2026-07 (inventory dated 2026-07-31) · EIA-860M Preliminary Monthly Electric Generator Inventory · eia.gov/…/july_generator2026.xlsx · eia.gov/…/eia860m

Nameplate capacity
424 MW
401 MW net summer
Generating units
8
In service
1967–1968
EIA plant ID
448

Where it is

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County
Merced County, California
Coordinates
37.0692, -121.0772
Balancing authority
CISO
Sector
Electric Utility

Units, technology and status

Operator of record
California Dept. of Water Resources
Primary energy source
Pumped storage
Technologies
Hydroelectric Pumped Storage
Status
Operating

Every plant California Dept. of Water Resources reports to EIA →

W R Gianelli: FAQ

Where is W R Gianelli?
In Merced County, California (CA). The map on this page is placed at the coordinates EIA files for the plant, which locate the site rather than any individual unit.
How big is W R Gianelli?
424 MW of nameplate capacity across 8 units, as of the EIA-860M release for 2026-07.
Who owns W R Gianelli?
EIA-860M names California Dept. of Water Resources as the reporting entity. That is the operator of record on the survey, which is not always the ultimate owner.
Is this the same as W R Gianelli LLC?
Probably, but EIA-860M does not say. The survey records a plant name and a reporting entity — California Dept. of Water Resources here — not the project company that holds the asset. Project companies are commonly registered as an LLC carrying the plant's name, so a search for "W R Gianelli LLC" usually means this site. This page shows only what EIA files, and does not assert a corporate structure it cannot see.
Is W R Gianelli still running?
EIA-860M files it as "Operating" for 2026-07. Statuses change monthly, and this page follows the monthly release.