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226.1 MW Wind operating in Dewey, OK — Southwest Power Pool
226.1 MW
Nameplate Capacity
1
Generators
unit
Onshore Wind Turbine
Technology
2014
Operating Since
Coordinates
35.9789, -98.7103
County
Dewey, 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 | Mammoth Plains Wind Project | NextEra Energy | — |
| Owner(s) | Mammoth Plains Wind Project | NextEra Energy | — |
| Status | Operating | operating | — |
Mammoth Plains is a 226.1 MW wind power plant located in Dewey County, Oklahoma. The facility began operating in 2014 and is owned by NextEra Energy, with Mammoth Plains Wind Project listed as the EIA operator. The plant utilizes a single generator consisting of multiple onshore wind turbines. Specifically, it employs GE1.7-100 model turbines manufactured by GE Wind, each with a rotor diameter of 100 meters and a hub height of 80 meters.
In the most recent year of record, Mammoth Plains generated 719,868 MWh of electricity, achieving a capacity factor of 36.3%. The plant operates within the Southwest Power Pool (SPP) balancing authority and the Midwest Reliability Organization (MRO) NERC region. Mammoth Plains ranks as the 19th largest wind farm in Oklahoma out of 57, and 209th nationally out of 734 wind facilities. Recent news coverage of the plant has focused on regulatory matters.
Generated from EIA, GEM, and public data sources
ISO/RTO
SPP
Market
ISO/RTO Member
NERC Region
MRO — Midwest Reliability Organization
Balancing Authority
45.0K MWh
Latest Month
719.9K MWh
Annual Generation
36.3%
Capacity Factor
2014
$1,650/kW
Est. Construction Cost
Total estimated cost: $373.1M
Market Position
ISO/RTO Market
SPP
LMP Node
SPS.MAMMOTHWND
Pricing Hub
SPP South Hub
Location Type
Settlement Location
Node Source
Curated node match
Last updated 2026-04-19
View all articlesSouthwest Power Pool (SWPP)
Grid Voltage
345.0 kV
Regulatory Status
NR — Non-Regulated
Entity Type
Independent Power Producer
Sector
IPP Non-CHP