75 MW BESS operating in Maricopa, AZ — Arizona Public Service Company
75 MW
Nameplate Capacity
1
Generators
unit
Batteries
Technology
2025
Operating Since
Coordinates
33.4096, -112.4116
County
Maricopa, AZ
Nearby Plants
| Field | EIA | GEM | Wikidata |
|---|---|---|---|
| Operator | Pluto Energy Storage, LLC | — | — |
| Owner(s) | Pluto Energy Storage, LLC | — | — |
| Status | Operating | — | — |
Pluto Energy Storage is a 75 MW battery energy storage system (BESS) located in Maricopa County, Arizona. The facility, which began operating in 2025, is owned and operated by Pluto Energy Storage, LLC. It consists of a single generator utilizing battery technology with a duration of 4 hours. The plant's primary fuel is listed as MWH, indicating it draws power from the grid to charge its batteries. Pluto Energy Storage ranks as the 51st largest power plant in Arizona out of 68, and 552nd nationally out of 1205 facilities.
The facility operates within the Arizona Public Service Company balancing authority and the Western Electricity Coordinating Council (WECC) NERC region. Financial data indicates a power purchase agreement (PPA) price of $13.96 per MWh, as reported in FERC Electric Quarterly Reports (EQR).
Generated from EIA, GEM, and public data sources
NERC Region
WECC
Balancing Authority
Arizona Public Service Company
Grid Voltage
69 kV
Regulatory Status
NR
Entity Type
Independent Power Producer
Sector
IPP Non-CHP
−1.4K MWh
Net Charging
-12.2K MWh
Annual Net Energy
-3.7%
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.
$14.0/MWh
PPA Price
Pluto Energy Storage, LLC
Contract Seller
This plant is outside organized wholesale electricity markets (ISOs/RTOs). Nodal pricing data is not available.
Last updated 2026-03-26
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