# San Luis (William R. Gianelli) Powerplant

CAISO asset profile · https://askthegrid.com/assets/facilities/san-luis-william-r-gianelli-powerplant

Bureau of Reclamation - Merced County - CAISO

The William R. Gianelli Powerplant is a 424 MW, eight-unit pumped-storage plant that moves water between O'Neill Forebay and San Luis Reservoir. Owned by the Bureau of Reclamation and operated by California's Department of Water Resources, it is both a grid-scale storage asset and a working part of the joint state-federal water system serving the State Water Project and Central Valley Project.

## Metrics

- **Nameplate capacity:** 424 MW — Canonical EIA plant baseline.
- **Registry anchor:** Plant 448 — plant-448

## Facts

- **Technology:** Hydroelectric Pumped Storage
- **Operator:** California Department of Water Resources

## Sources

- [cawaterlibrary.net](http://cawaterlibrary.net/wp-content/uploads/2023/10/Bulletin-200-Vol-IV.pdf) — cawaterlibrary.net · public_source — Source retained for exact-record publication review.
- [ecf.cofc.uscourts.gov](https://ecf.cofc.uscourts.gov/cgi-bin/show_public_doc?2015cv1563-21-0) — ecf.cofc.uscourts.gov · authoritative — Source retained for exact-record publication review.

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Canonical page: https://askthegrid.com/assets/facilities/san-luis-william-r-gianelli-powerplant
Website: [Bureau of Reclamation](https://www.usbr.gov)

Source: Ask the Grid — https://askthegrid.com/