- Combustion
- Operating
- 10 · 100 · 1,000 MW
Map
- Combustion
- Operating
Marion: location. Basemap: Protomaps, © OpenStreetMap contributors, ODbL.
Marion
Power plant · Gas, combustion turbine
Key facts
Power plant · Gas, combustion turbineran 35% of 2025 Operating- Capacity
- Capacity: sourceEIA-860M · Open licenseMW
- Commissioned
- 1963
- Net generation, 2025
- 767,048 MWh
- Grid
- 161 kV, 67 kV to Southern Illinois Elec Coop (MISO)
- Location
- Williamson County, Illinois
- Operated by
- Southern Illinois Power CoopSourceEIA-860M Preliminary Monthly Electric Generator Inventory
Operations
- Net generation, 2025
- 767,048
MWh - Fuel burned, 2025
- 12,295,617
MMBtu - Capacity factor, 2025
- 35.2
% - Heat rate, 2025
- 16,030
Btu/kWh
| Year | Net generation (MWh) | Fuel burned (MMBtu) | Capacity factor | Heat rate (Btu/kWh) |
|---|---|---|---|---|
| 2026 (8 of 12 months) | 579,198 | 9,311,604 | — | 16,077 |
| 2025 | 767,048 | 12,295,617 | 35.2% | 16,030 |
| 2024 | 746,246 | 11,766,885 | 34.1% | 15,768 |
| 2023 | 708,926 | 10,848,940 | 32.5% | 15,303 |
| 2022 | 784,259 | 12,223,433 | 35.9% | 15,586 |
| 2021 | 669,385 | 8,895,607 | 30.7% | 13,289 |
| 2020 | 911,493 | 11,057,217 | 41.7% | 12,131 |
| 2019 | 1,652,019 | 19,049,361 | 75.7% | 11,531 |
| 2018 | 1,718,914 | 19,647,515 | 78.8% | 11,430 |
| 2017 | 1,636,123 | 18,786,288 | 75.0% | 11,482 |
| 2016 | 1,655,061 | 19,160,026 | 75.7% | 11,577 |
| 2015 | 1,800,859 | 20,601,918 | 82.6% | 11,440 |
| 2014 | 1,726,722 | 19,934,943 | 79.2% | 11,545 |
| 2013 | 1,719,444 | 19,961,550 | 78.8% | 11,609 |
| 2012 | 1,739,521 | 21,078,503 | 79.5% | 12,117 |
| 2011 | 1,860,303 | 22,190,493 | 85.3% | 11,928 |
| 2010 | 1,795,382 | 21,150,927 | 82.3% | 11,781 |
| 2009 | 1,734,162 | 20,225,365 | 79.5% | 11,663 |
| 2008 | 1,523,699 | 18,516,243 | 69.7% | 12,152 |
| 2007 | 1,781,203 | 22,133,282 | 81.7% | 12,426 |
| 2006 | 1,856,060 | 23,922,626 | 85.1% | 12,889 |
| 2005 | 1,835,312 | 23,430,292 | 84.1% | 12,766 |
| 2004 | 1,913,634 | 23,032,933 | 87.5% | 12,036 |
| 2003 | 1,429,045 | 16,228,017 | 65.5% | 11,356 |
| 2002 | 1,136,616 | 13,908,109 | 52.1% | 12,236 |
| 2001 | 1,364,295 | 17,183,413 | 62.5% | 12,595 |
How these are worked out
Net generation and fuel burned are the monthly figures EIA publishes in its bulk electricity file, from the plant's Form 923 reports; a year is the sum of its months. Capacity factor is a full year's net generation over today's nameplate capacity times the hours in that year (8,784 in a leap year), so a plant uprated or partly retired since reads against its current size; heat rate is fuel burned over net generation, for plants that burn fuel. A year with fewer than twelve months stated has no capacity factor, and a value outside the plausible range is left blank rather than shown. By month, the charts apply the same rules to each month's own hours and fuel.
Sources
3 sourcesSources
- EIA-860M
- GEMGlobal Integrated Power Tracker, Global Energy Monitor, September 2026 release (https://globalenergymonitor.org/projects/global-integrated-power-tracker), CC BY 4.0. Modified by Inframation: TransitionZero-sourced rows removed; statuses and technologies mapped to Inframation's vocabulary; figures aggregated. Copyright © Global Energy Monitor. Global Integrated Power Tracker, September 2026 release. Distributed under a Creative Commons Attribution 4.0 International License.
- EIASource: U.S. Energy Information Administration, Electricity bulk data (Form EIA-923 monthly plant series)