ExxonMobil Oil Joliet Refinery
Natural gas power plant · Will County, Illinois
Nameplate capacity
43 MW
Rank in Illinois
#133
of 580 plants
In service since
1986
May 1986
Details
- Primary fuel
- Natural gas
- Technology
- Other Gases
- Operator
- ExxonMobil Oil Corp
- County
- Will County
- Generating units
- 3
- Share of state capacity
- 0.08%
- Rank among natural gas plants in Illinois
- #39 of 72
- EIA plant code
- 50627
Generating units
| Unit | Technology | Nameplate | Summer | Online | Status |
|---|---|---|---|---|---|
| GTG1 | Other Gases | 26 MW | 22 MW | 1987 | Operating |
| MG | Other Gases | 11 MW | 11 MW | 1986 | Operating |
| STG1 | Other Gases | 6.5 MW | 3.3 MW | 1987 | Out of service and NOT expected to return to service in next calendar year |
Nameplate is the maximum rated output; summer capacity is what the unit can reliably deliver on a hot day, which is typically lower.
Similarly sized plants in Illinois
| Salt Creek Township Solar, LLC | Solar | 50 MW |
| Coffeen Solar BESS | Solar | 46 MW |
| Waterloo | Natural gas | 38 MW |
| Princeton (IL) | Natural gas | 38 MW |
About this data
From EIA’s inventory of operable generators, May 2026 release. Capacity is nameplate — the maximum rated output of the equipment, not what the plant actually generates over a year, which depends on how often it runs. A 43 MW solar plant and a 43 MW nuclear plant have the same entry here and produce very different amounts of electricity.
“In service since” is the earliest in-service date among the units still listed, so a site rebuilt around newer equipment can read as younger than the site itself. All Illinois power plants · What Illinois actually generates