Southwestern — United States of America
Gas power plant in Oklahoma, United States of America. Approximate location 35.1009, -98.3524.
GasOklahomaUnited States of AmericaSteamCO₂ measured
Southwestern is a 657 MW gas power station in Oklahoma, United States of America. It is operated by Public Service Co of Oklahoma. Based on reported annual generation of 627 GWh, it can supply roughly 179k homes. It ranks #957 of 10,884 United States of America power plants by installed capacity. Commissioned in 1974, it is around 52 years old — an older, legacy facility. Its annual emissions of 711,730 t CO₂/yr (US EPA GHGRP) are equivalent to about 166k cars driven for a year. In context, gas supplies about 40.0% of United States of America's electricity; the national grid averages 384 gCO₂/kWh (43.0% low-carbon) (2025).
Plant data: WRI Global Power Plant Database (CC BY 4.0), id USA0002964.
Data status
Known data
Calculated from dataset
Known, modelled and calculated values are kept separate. Missing fields are shown as unavailable.
Data provenance
Source of the capacity and fuel values:
capacity: GEM · 2026 · L100000402234; fuel: WRI GPPD
In context: how this plant compares
At 657 MW, Southwestern is well above the median gas plant in United States of America (121.2 MW). Technically it is described as Steam. Gas plants burn natural gas either in open-cycle turbines for fast peaking, or in combined-cycle units that recover exhaust heat in an HRSG to reach roughly 55–62% efficiency — the cleanest-burning fossil option.
Capacity comparison computed from the WRI Global Power Plant Database; fuel-type context is general engineering background.
711,730 t CO₂/yr — in everyday terms
This facility's annual emissions are roughly equivalent to:
Equivalencies via US EPA Greenhouse Gas Equivalencies; emissions per US EPA GHGRP (measured for US EPA/EU ETS, modelled for Climate TRACE).
Key facts
- Load factor
- 11%, from 627 GWh of reported generation; the median for 1622 gas plants in United States of America that report generation is 26%
- Generation trend
- 470 GWh in 2013 and 627 GWh in 2019 (+33%)
- Highest and lowest year
- 2019: 627 GWh; 2014: 352 GWh
- Share of United States of America gas capacity
- less than 0.1% of 789,950 MW across 2,165 plants in this dataset
- Age among peers
- 236 of 1,973 dated gas plants in United States of America are older
Calculated from the capacity and generation records in this dataset (WRI Global Power Plant Database (CC BY 4.0)).
Reported generation trend
Annual generation (GWh), WRI Global Power Plant Database (CC BY 4.0).
Owner
Operated by Public Service Co of Oklahoma. All plants by this company →
Local climate & thermal context
This gas plant burns natural gas in a turbine — often in a combined-cycle setup — to generate electricity. It sits in a humid subtropical climate (Köppen Cfa) — Northern Hemisphere, latitude 35.1°N — which shapes how much energy it can produce and how its output varies through the year.
Monthly mean temperature
Heating degree-days here run 26% below the median power plant in this dataset — a proxy for how much extra energy heated equipment must replace through its surfaces in winter.
Climate heat-demand index: 40/100 — this site sits in the mid third of the power plants we cover by heating degree-days.
A gas turbine here also runs ~1% below its ISO (15°C) rating at this annual mean (typical CCGT curve, estimate).
Climate normals: WorldClim 2.1 (1970–2000 monthly normals, 10 arc-min, CC BY 4.0); zone: Köppen-Geiger world climate classification (Kottek et al. 2006, 0.5° grid). Degree-days & heat-demand index computed by PowerAtlas — a modelled heat-demand proxy, not a measured site figure.
Site climate & environmental severity
This site sits in a moderately corrosive environment (estimated ISO 9223 class C3 — Medium), with humidity / wetness the leading environmental stress.
Indicative estimate via the ISO 9223:2012 informative method (atmospheric corrosivity from temperature, time-of-wetness and airborne salinity), using WorldClim climate normals, the Köppen-Geiger class and coast distance. Indicative, not a measured corrosion rate.
How it compares & nearby plants
The #434 largest gas power plant of 2165 in United States of America by capacity.
United States of America has 2165 gas power plants in this dataset, together about 789,950 MW of capacity.
Nearby power plants
- Anadarko Plant · Gas · 534.9 MW · Oklahoma
- WFEC GenCo LLC · Gas · 90 MW · Oklahoma
- Pine Ridge · Solar · 3 MW · Oklahoma
- Cyril · Solar · 5 MW · Oklahoma
- Blue Canyon Windpower VI LLC · Wind · 99.8 MW · Oklahoma
- Minco Wind IV LLC · Wind · 130 MW · Oklahoma
Location
Coordinates 35.1009, -98.3524 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.
Frequently asked questions
What type of power plant is Southwestern?
Southwestern is a 657 MW gas power plant in Oklahoma, United States of America, commissioned in 1974.
How much electricity does Southwestern generate?
Southwestern generates about 627 GWh of electricity per year.
Who operates Southwestern?
Southwestern is operated by Public Service Co of Oklahoma.
How much CO₂ does Southwestern emit?
Southwestern has measured emissions of about 711,730 tonnes of CO₂ per year (US EPA GHGRP).