| State Rank | County | Net Generation (Past Year) | Power Plants |
|---|
| #37 | Cook County, IL | 491.6 GWh | 77 |
| #1 | Will County, IL | 28.4 TWh | 40 |
| #34 | Stephenson County, IL | 540.5 GWh | 26 |
| #33 | DuPage County, IL | 591.2 GWh | 25 |
| #51 | Winnebago County, IL | 188.8 GWh | 23 |
| #4 | LaSalle County, IL | 19.9 TWh | 23 |
| #59 | McHenry County, IL | 32.6 GWh | 21 |
| #30 | Kankakee County, IL | 665.4 GWh | 18 |
| #57 | Whiteside County, IL | 47.4 GWh | 18 |
| #13 | McLean County, IL | 3.1 TWh | 15 |
| #28 | DeKalb County, IL | 672.2 GWh | 15 |
| #56 | Kane County, IL | 71.0 GWh | 14 |
| #16 | Livingston County, IL | 2.4 TWh | 13 |
| #9 | Lee County, IL | 5.9 TWh | 12 |
| #48 | Champaign County, IL | 256.5 GWh | 12 |
| #3 | Ogle County, IL | 19.9 TWh | 12 |
| #18 | Bureau County, IL | 2.2 TWh | 11 |
| #14 | Sangamon County, IL | 2.9 TWh | 11 |
| #38 | Madison County, IL | 481.3 GWh | 10 |
| #61 | Clinton County, IL | 11.5 GWh | 10 |
| #24 | Vermilion County, IL | 1.1 TWh | 10 |
| #12 | Tazewell County, IL | 3.7 TWh | 10 |
| #2 | Grundy County, IL | 22.3 TWh | 10 |
| #53 | Peoria County, IL | 90.9 GWh | 9 |
| #6 | St. Clair County, IL | 12.2 TWh | 9 |
| #41 | Lake County, IL | 401.5 GWh | 8 |
| #42 | Morgan County, IL | 387.0 GWh | 8 |
| #26 | Williamson County, IL | 784.6 GWh | 8 |
| #15 | Christian County, IL | 2.7 TWh | 7 |
| #36 | Clay County, IL | 496.2 GWh | 7 |
| #5 | Rock Island County, IL | 16.3 TWh | 7 |
| #21 | Logan County, IL | 1.4 TWh | 7 |
| #8 | Randolph County, IL | 6.7 TWh | 6 |
| #43 | Marshall County, IL | 382.4 GWh | 6 |
| #17 | Macon County, IL | 2.2 TWh | 6 |
| #20 | Henry County, IL | 1.7 TWh | 6 |
| #66 | Knox County, IL | 4.4 GWh | 6 |
| #35 | McDonough County, IL | 517.3 GWh | 5 |
| #46 | Cass County, IL | 331.8 GWh | 4 |
| #32 | White County, IL | 601.3 GWh | 4 |
| #7 | De Witt County, IL | 8.9 TWh | 4 |
| #25 | Iroquois County, IL | 816.3 GWh | 4 |
| #62 | Macoupin County, IL | 9.5 GWh | 4 |
| #44 | Coles County, IL | 379.6 GWh | 4 |
| #75 | Marion County, IL | 964.0 MWh | 4 |
| #70 | Jo Daviess County, IL | 3.5 GWh | 4 |
| #22 | Mason County, IL | 1.3 TWh | 4 |
| #52 | Pike County, IL | 134.8 GWh | 4 |
| #31 | Woodford County, IL | 651.1 GWh | 3 |
| #19 | Shelby County, IL | 1.8 TWh | 3 |
| #40 | Perry County, IL | 401.9 GWh | 3 |
| #69 | Putnam County, IL | 3.7 GWh | 3 |
| #54 | Montgomery County, IL | 85.1 GWh | 3 |
| #64 | Boone County, IL | 8.1 GWh | 3 |
| #47 | Clark County, IL | 304.3 GWh | 3 |
| #50 | Fayette County, IL | 235.3 GWh | 3 |
| #23 | Ford County, IL | 1.2 TWh | 3 |
| #60 | Fulton County, IL | 31.5 GWh | 3 |
| #10 | Kendall County, IL | 5.5 TWh | 3 |
| #27 | Piatt County, IL | 679.0 GWh | 2 |
| #73 | Adams County, IL | 2.2 GWh | 2 |
| #76 | Monroe County, IL | 491.0 MWh | 2 |
| #29 | Douglas County, IL | 667.0 GWh | 2 |
| #45 | Saline County, IL | 347.7 GWh | 2 |
| #63 | Jackson County, IL | 9.0 GWh | 2 |
| #11 | Jasper County, IL | 3.7 TWh | 2 |
| #72 | Henderson County, IL | 2.5 GWh | 1 |
| #58 | Scott County, IL | 38.7 GWh | 1 |
| #49 | Jersey County, IL | 249.7 GWh | 1 |
| #68 | Franklin County, IL | 3.8 GWh | 1 |
| #39 | Stark County, IL | 406.4 GWh | 1 |
| #67 | Jefferson County, IL | 4.3 GWh | 1 |
| #78 | Effingham County, IL | 56.0 MWh | 1 |
| #55 | Warren County, IL | 75.8 GWh | 1 |
| #65 | Richland County, IL | 4.4 GWh | 1 |
| #71 | Carroll County, IL | 3.0 GWh | 1 |
| #74 | Brown County, IL | 1.3 GWh | 1 |
| #77 | Moultrie County, IL | 284.0 MWh | 1 |
Net Generation data is based on the last 12 months since Dec 2025
