Search
Search plants, projects, owners, and states
Search plants, projects, owners, and states
152 MW Solar under construction in Mayes, OK — Southwest Power Pool
152 MW
Nameplate Capacity
1
Generators
unit
Solar Photovoltaic
Technology
—
Operating Since
Coordinates
36.3316, -95.2293
County
Mayes, OK
Nearby Plants
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 | Leeward Asset Management, LLC | Leeward Energy | — |
| Owner(s) | Leeward Asset Management, LLC | Leeward Energy | — |
| Status | Under construction | construction | — |
GEM identifies the owner as Leeward Energy
This entity is not yet in the GEM ownership database — chain unavailable.
Twelvemile Solar 1 & 2 is a 152 MW solar photovoltaic power plant located in Mayes County, Oklahoma. The plant is owned and operated by Leeward Asset Management, LLC. It utilizes fixed-tilt solar tracking technology. The plant is the second-largest solar facility in Oklahoma out of six, and ranks 344th nationally out of 639 solar plants.
The plant connects to the Southwest Power Pool (SPP) balancing authority, within the Midwest Reliability Organization (MRO) NERC region. The facility consists of one generator and uses solar energy as its primary fuel source.
Generated from EIA, GEM, and public data sources
ISO/RTO
SPP
Market
ISO/RTO Member
NERC Region
MRO — Midwest Reliability Organization
Balancing Authority
No generation data available for this plant.
2023
$1,543/kW
Est. Construction Cost
Total estimated cost: $234.5M
Point of Interconnection
Nearest Substation
Pryor Junction Substation · 138 kV
Substation Distance
2.068 km
Coord Source
OSM spatial
Market Position
ISO/RTO Market
SPP
LMP Node
CSWS.NUEN.CSI1
Pricing Hub
SPP South Hub
Location Type
Settlement Location
Node Source
Curated node match
Last updated 2026-03-26
View all articlesNo ask pi reports yet for this entity.
ask pi about Twelvemile Solar 1Southwest Power Pool (SWPP)
Grid Voltage
—
Regulatory Status
NR — Non-Regulated
Entity Type
Independent Power Producer
Sector
IPP Non-CHP