Mammoth G2 — Plant Summary
- EIA Plant ID
- 10481
- Capacity
- 15 MW
- Primary Fuel
- Geothermal
- Technology
- Geothermal
- Status
- Operating
- Location
- Mono, CA
- Operating Since
- 1990
- Generators
- 3
- Operator
- Ormat Nevada Inc
- Parent Company
- —
- Annual Generation
- 82,307 MWh
- Capacity Factor
- 62.5%
- Balancing Authority
- California Independent System Operator
- ISO/RTO
- CAISO
- NERC Region
- WECC
Mammoth G2
OperatingGeothermal
Ranked #29 of 33 Geothermal plants in CA#60 of 70 nationally
15 MW Geothermal operating in Mono, CA — California Independent System Operator
EIAGEMWD
15 MW
Nameplate Capacity
3
Generators
units
Geothermal
Technology
1990
Operating Since
Location
Coordinates
37.6464, -118.9092
County
Mono, CA
Nearby Plants
- Mammoth G3Geothermal15 MW · 0.1 km
- Mammoth G1Geothermal10 MW · 0.5 km
- CD4Geothermal44.4 MW · 0.6 km
Ownership & Operator
Owner data does not fully agree across sources.
EIA typically reports the operating utility, while GEM resolves to the financial owner or parent corporation. Both can be correct.
| Field | EIA | GEM | Wikidata |
|---|---|---|---|
| Operator | Ormat Nevada Inc | Ormat Technology Inc [100%] | — |
| Owner(s) | Mammoth Pacific LP | Ormat Technology Inc [100%] | — |
| Status | Operating | operating | — |
Ownership Chain
GEM identifies the owner as Ormat Technology Inc [100%]
This entity is not yet in the GEM ownership database — chain unavailable.
About
Mammoth G2 is a 15 MW geothermal power plant located in Mono County, California. The plant began operating in 1990 and has three generators utilizing geothermal technology. Ormat Nevada Inc. is the plant's operator.
The plant's latest annual generation was 82,307 MWh, resulting in a capacity factor of 62.5%. Mammoth G2 operates within the California Independent System Operator (CAISO) balancing authority and the Western Electricity Coordinating Council (WECC) NERC region. It is ranked as the 29th largest power plant in California out of 33, and 61st nationally out of 70.
Generated from EIA, GEM, and public data sources
Engineering & Generators
Grid Context
NERC Region
WECC
Balancing Authority
California Independent System Operator
Grid Voltage
33 kV
Regulatory Status
NR
Entity Type
Independent Power Producer
Sector
IPP Non-CHP
Generation
7.9K MWh
Latest Month
82.3K MWh
Annual Generation
62.5%
Capacity Factor
Jan 2022 – Dec 2024
Financial Data
No financial data available for this plant.
Pricing & Market Data
HIGH confidencePoint of Interconnection
Nearest Substation
Mommoth Pacific 1
Substation Distance
0.579 km
Coord Source
OSM spatial
Market Position
ISO/RTO Market
CAISO
LMP Node
CONTROLX_1_N009
Pricing Hub
TH_SP15_GEN-APND
Secondary Zone
TH_NP15_GEN-APND
Location Type
Pricing Node
Node Source
Curated node match
News & Articles (10)Beta
General
Ormat signs 15 MW PPA for Mammoth 2 plant with Calpine
Ormat Technologies has secured a new PPA for up to 15 MW from its Mammoth 2 geothermal power plant in California replacing a lower-priced PPA with SCE.
ThinkGeoEnergy·1 years ago
General
Ormat signs 15 MW PPA for Mammoth 2 plant with Calpine
Ormat Technologies has secured a new PPA for up to 15 MW from its Mammoth 2 geothermal power plant in California replacing a lower-priced PPA with SCE.
ThinkGeoEnergy·1 years ago
General
Ormat signs 15 MW PPA for Mammoth 2 plant with Calpine
Ormat Technologies has secured a new PPA for up to 15 MW from its Mammoth 2 geothermal power plant in California replacing a lower-priced PPA with SCE.
ThinkGeoEnergy·1 years ago
General
Ormat signs 15 MW PPA for Mammoth 2 plant with Calpine
Ormat Technologies has secured a new PPA for up to 15 MW from its Mammoth 2 geothermal power plant in California replacing a lower-priced PPA with SCE.
ThinkGeoEnergy·1 years ago
Last updated 2026-03-26
View all 10 articles