25.2 MW Hydro operating in Merced, CA — California Independent System Operator
25.2 MW
Nameplate Capacity
6
Generators
units
Hydroelectric Pumped Storage
Technology
1967
Operating Since
Coordinates
37.0987, -121.0477
County
Merced, CA
Nearby Plants
| Field | EIA | GEM | Wikidata |
|---|---|---|---|
| Operator | U S Bureau of Reclamation | — | — |
| Owner(s) | U S Bureau of Reclamation | — | — |
| Status | Operating | — | — |
The O'Neill power plant, located in Merced County, California, has a total capacity of 25.2 MW. The plant began operating in 1967 and utilizes hydroelectric pumped storage technology. It is owned and operated by the U.S. Bureau of Reclamation. The primary fuel source for the plant is water (WAT). The facility consists of 6 generators.
The O'Neill plant operates within the California Independent System Operator (CAISO) balancing authority and the Western Electricity Coordinating Council (WECC) NERC region. It is ranked as the 87th largest power plant in California out of 247, and nationally it is ranked 444 out of 1464.
Generated from EIA, GEM, and public data sources
NERC Region
WECC
Balancing Authority
California Independent System Operator
Grid Voltage
72.5 kV
Regulatory Status
RE
Entity Type
Federal
Sector
Electric Utility
−6.5K MWh
Net Charging
-65.9K MWh
Annual Net Energy
-30.0%
Capacity Factor
Positive values indicate net discharge (generation exceeds station load). Negative values indicate net charging. Pure battery storage plants are typically net negative due to round-trip efficiency losses.
No financial data available for this plant.
Market Position
ISO/RTO Market
CAISO
LMP Node
ONEILPMP_7_N002
Pricing Hub
TH_NP15_GEN-APND
Secondary Zone
TH_ZP26_GEN-APND
Location Type
Pricing Node
Node Source
Curated node match
Last updated 2026-03-26
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