Geysers Power Company, LLC - Sonoma County - CAISO
The EIA-anchored Geysers Unit 5-20 profile aggregates 12 geothermal generators in Sonoma County with 1,236 MW of nameplate capacity. Geysers Power Company is part of Calpine, which Constellation acquired in January 2026.
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Canonical EIA plant baseline.
plant-286
Similar plants ranked by technology, capacity, and distance.
Operating generator records and technology attributes reported through EIA-860.
| Generator | Capacity | Technology | Operation | Status |
|---|---|---|---|---|
| U11 | 118.8 MW 68 MW summer | Geothermal Geothermal · ST | Dec 1975 | Operating |
| U12 | 118.8 MW 51 MW summer | Geothermal Geothermal · ST | Aug 1979 | Operating |
| U13 | 139.8 MW 65 MW summer | Geothermal Geothermal · ST | Apr 1980 | Operating |
| U14 | 124.2 MW 60 MW summer | Geothermal Geothermal · ST | Feb 1980 | Operating |
| U16 | 124.2 MW 60 MW summer | Geothermal Geothermal · ST | Oct 1985 | Operating |
| U17 | 124.2 MW 60 MW summer | Geothermal Geothermal · ST | Nov 1982 | Operating |
| U18 | 124.2 MW 60 MW summer | Geothermal Geothermal · ST | Nov 1983 | Operating |
| U20 | 124.2 MW 50 MW summer | Geothermal Geothermal · ST | Oct 1985 | Operating |
| U5 | 59.4 MW 45 MW summer | Geothermal Geothermal · ST | Apr 1971 | Operating |
| U6 | 59.4 MW 45 MW summer | Geothermal Geothermal · ST | Apr 1971 | Operating |
| U7 | 59.4 MW 40 MW summer | Geothermal Geothermal · ST | Jul 1972 | Operating |
| U8 | 59.4 MW 40 MW summer | Geothermal Geothermal · ST | Jul 1972 | Operating |
Monthly EIA generation history and recent market-resource behavior where linked telemetry is available.
Monthly generation is reported through EIA-923. Capacity factor uses the current EIA nameplate capacity and is shown only for complete calendar years.
Deterministic links to ERCOT market resources, price records, outage disclosures, queue records, and nearby infrastructure. Candidate joins remain labeled until corroborated.
Source-backed project transactions, agreements, land records, permits, and environmental disclosures. Portfolio and adjacent-project facts remain explicitly scoped.
Parties, market resources, and identifiers tied to this asset, with owner, operator, developer, EPC, compliance provider, and interconnecting entity roles kept separate.
| Largest reported plants | Capacity | State | |
|---|---|---|---|
| Geysers Unit 5-20Current | 1,236 MW | CA | |
| Calistoga Power Plant | 176.4 MW | CA | |
| Sonoma California Geothermal | 78 MW | CA | |
| Aidlin Geothermal Power Plant | 25 MW | CA |
Portfolio membership follows the latest EIA-860 reporting entity. It does not imply ultimate ownership.
View full reporting portfolioProject milestones and public references behind the asset profile.
Unit U5 at Geysers Unit 5-20 (plant code 286) entered commercial operation.
Units U7 and U8 entered service at Geysers Unit 5-20.
Unit U11 entered service at Geysers Unit 5-20.
Unit U12 entered service at Geysers Unit 5-20.
Cooling tower replacement project for Unit 18 (Socrates plant) documented in California Energy Commission docket.
Geysers Power Company, LLC filed a consolidated petition for staff-approved modifications covering Units 16, 18, and 20.
Constellation Energy Corporation completed its acquisition of Calpine Corporation from Energy Capital Partners, making Constellation the ultimate parent company.
Answered from the published record above. Questions whose inputs this profile does not carry are omitted rather than estimated.
Geysers Unit 5-20 has a reported capacity of 1,236 MW. Source: EIA Form 860M.
Geysers Unit 5-20 is a geothermal facility in Sonoma County, CA, participating in the CAISO market.
Geysers Unit 5-20 is in Sonoma County, CA, inside the CAISO balancing area.
Geysers Unit 5-20 is operated by Geysers Power Co LLC according to the EIA generator inventory. Reporting membership does not by itself establish ultimate ownership.
Geysers Unit 5-20 reported 4,215.8 GWh over the twelve months to 2026-04. Figures are net generation as filed to EIA-923.
By capacity, Geysers Unit 5-20 ranks #1 of 63 operating plants of the same technology nationally. It ranks #1 of 30 in CA.
Plants within 25 km, nearest first, regardless of technology. Proximity is straight-line distance between mapped plant coordinates; it does not by itself establish a shared point of interconnection.
Unit U14 entered service at Geysers Unit 5-20.
EIA-860 lists generator U13 with this operating date.
EIA-860 lists generator U17 with this operating date.
EIA-860 lists generator U18 with this operating date.
Units U20 and U16 entered commercial operation, completing the 12-generator grouping at Geysers Unit 5-20.
Calpine completed the acquisition of 14 Geysers power plants (12 Sonoma County and 2 Lake County) from Pacific Gas & Electric Company for approximately $212.8 million. EIA plant 286 is included in the Sonoma County grouping.
Calpine completed a leveraged lease financing transaction for West Ford Flat and Bear Canyon projects within the Geysers lease facility, generating $81.0 million in gross proceeds.
Calpine and the City of Santa Rosa completed the Santa Rosa Geysers Recharge Project, a 40-mile pipeline delivering an average of 11 million gallons per day of treated wastewater to The Geysers reservoir to support steam pressure and generation.