277.3 MW Batteries (72 MW) + Solar Photovoltaic (205 MW) operating in Fresno, CA — California Independent System Operator
277.3 MW
Nameplate Capacity
3
Generators
units
Hybrid (2)
Technology
Batteries + Solar Photovoltaic
2016
Operating Since
Coordinates
36.5814, -120.4045
County
Fresno, CA
Nearby Plants
| Field | EIA | GEM | Wikidata |
|---|---|---|---|
| Operator | Southern Power Co | Southern Power | — |
| Owner(s) | RE Tranquillity LLC, SP Tranquillity Solar Storage, LLC | Canadian Solar [49%]; Southern Power Co [51%] | — |
| Status | Operating | operating | — |
GEM identifies the owner as Canadian Solar [49%]; Southern Power Co [51%]
This entity is not yet in the GEM ownership database — chain unavailable.
RE Tranquillity is a hybrid solar and battery energy storage system (BESS) located in Fresno County, California. The plant, operated by Southern Power Co, has a total capacity of 277.3 MW and commenced operations in 2016. It consists of three generators utilizing both solar photovoltaic and battery technologies. The BESS component has a storage capacity of 128 MWh, providing a duration of approximately 3.46 hours and employing lithium-ion battery (LIB) chemistry. The solar array uses single-axis tracking.
The plant operates within the California Independent System Operator (CAISO) balancing authority and the Western Electricity Coordinating Council (WECC) NERC region. RE Tranquillity's latest annual generation was 491,435 MWh, resulting in a capacity factor of 20.2%. The plant ranks as the 43rd largest in California out of 112 plants and 181st nationally out of 514. Financial data indicates a power purchase agreement (PPA) price of $49.83 per MWh.
Generated from EIA, GEM, and public data sources
NERC Region
WECC
Balancing Authority
California Independent System Operator
Grid Voltage
230 kV
Regulatory Status
NR
Entity Type
Investor-Owned Utility
Sector
IPP Non-CHP
18.6K MWh
Latest Month
491.4K MWh
Annual Generation
20.2%
Capacity Factor
$56.1/MWh
LCOE (Levelized Cost)
$49.8/MWh
PPA Price
$-14.6/MWh
Energy Value
Market Position
ISO/RTO Market
CAISO
LMP Node
Q1032C2_7_N001
Pricing Hub
TH_NP15_GEN-APND
Secondary Zone
TH_ZP26_GEN-APND
Location Type
Pricing Node
Node Source
Curated node match
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Last updated 2026-03-14
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