| State Rank | County | Net Generation (Past Year) | Power Plants |
| #85 | Brown County, IL | 3.0 MWh | 1 |
| #84 | Hamilton County, IL | 42.0 MWh | 1 |
| #83 | Effingham County, IL | 75.0 MWh | 1 |
| #82 | Moultrie County, IL | 574.0 MWh | 1 |
| #81 | Monroe County, IL | 751.0 MWh | 2 |
| #80 | Adams County, IL | 2.1 GWh | 7 |
| #79 | Carroll County, IL | 2.8 GWh | 1 |
| #78 | Henderson County, IL | 2.9 GWh | 1 |
| #77 | Franklin County, IL | 4.2 GWh | 1 |
| #76 | Richland County, IL | 4.4 GWh | 2 |
| #75 | Lawrence County, IL | 4.7 GWh | 3 |
| #74 | Crawford County, IL | 5.4 GWh | 4 |
| #73 | Edgar County, IL | 7.3 GWh | 2 |
| #72 | Putnam County, IL | 7.6 GWh | 3 |
| #71 | Pulaski County, IL | 8.8 GWh | 2 |
| #70 | Jackson County, IL | 8.9 GWh | 6 |
| #69 | Jo Daviess County, IL | 11.4 GWh | 4 |
| #68 | Mercer County, IL | 16.0 GWh | 4 |
| #67 | Knox County, IL | 18.0 GWh | 10 |
| #66 | Clinton County, IL | 24.0 GWh | 13 |
| #65 | Boone County, IL | 25.5 GWh | 11 |
| #64 | Scott County, IL | 34.7 GWh | 1 |
| #63 | Jefferson County, IL | 42.2 GWh | 3 |
| #62 | McHenry County, IL | 58.8 GWh | 28 |
| #61 | Whiteside County, IL | 67.0 GWh | 22 |
| #60 | Warren County, IL | 77.9 GWh | 1 |
| #59 | Peoria County, IL | 89.1 GWh | 21 |
| #58 | Kane County, IL | 97.5 GWh | 21 |
| #57 | Montgomery County, IL | 97.5 GWh | 6 |
| #56 | Marion County, IL | 100.9 GWh | 4 |
| #55 | Pike County, IL | 151.5 GWh | 5 |
| #54 | Winnebago County, IL | 217.6 GWh | 25 |
| #53 | Macoupin County, IL | 221.9 GWh | 9 |
| #52 | Fayette County, IL | 228.1 GWh | 6 |
| #51 | Fulton County, IL | 262.8 GWh | 4 |
| #50 | Jersey County, IL | 265.7 GWh | 1 |
| #49 | Cass County, IL | 308.1 GWh | 5 |
| #48 | Clark County, IL | 328.3 GWh | 4 |
| #47 | Cumberland County, IL | 375.7 GWh | 1 |
| #46 | Morgan County, IL | 383.1 GWh | 9 |
| #45 | Marshall County, IL | 397.4 GWh | 9 |
| #44 | Perry County, IL | 404.1 GWh | 8 |
| #43 | Stark County, IL | 411.5 GWh | 2 |
| #42 | Champaign County, IL | 428.9 GWh | 20 |
| #41 | Coles County, IL | 472.0 GWh | 4 |
| #40 | Madison County, IL | 483.5 GWh | 16 |
| #39 | DuPage County, IL | 493.8 GWh | 26 |
| #38 | Lake County, IL | 506.4 GWh | 10 |
| #37 | Saline County, IL | 518.7 GWh | 3 |
| #36 | Clay County, IL | 520.2 GWh | 8 |
| #35 | McDonough County, IL | 537.3 GWh | 8 |
| #34 | Stephenson County, IL | 548.1 GWh | 32 |
| #33 | White County, IL | 611.5 GWh | 5 |
| #32 | Cook County, IL | 615.7 GWh | 86 |
| #31 | Woodford County, IL | 622.9 GWh | 4 |
| #30 | Kankakee County, IL | 697.9 GWh | 37 |
| #29 | DeKalb County, IL | 707.0 GWh | 34 |
| #28 | Douglas County, IL | 729.3 GWh | 3 |
| #27 | Iroquois County, IL | 794.8 GWh | 4 |
| #26 | Williamson County, IL | 818.0 GWh | 12 |
| #25 | Piatt County, IL | 949.4 GWh | 5 |
| #24 | Vermilion County, IL | 1.1 TWh | 13 |
| #23 | Mason County, IL | 1.3 TWh | 7 |
| #22 | Ford County, IL | 1.4 TWh | 5 |
| #21 | Logan County, IL | 1.6 TWh | 8 |
| #20 | Christian County, IL | 1.8 TWh | 7 |
| #19 | Henry County, IL | 1.8 TWh | 12 |
| #18 | Macon County, IL | 2.0 TWh | 10 |
| #17 | Bureau County, IL | 2.3 TWh | 20 |
| #16 | Livingston County, IL | 2.3 TWh | 24 |
| #15 | Sangamon County, IL | 2.9 TWh | 11 |
| #14 | McLean County, IL | 3.3 TWh | 17 |
| #13 | Jasper County, IL | 3.3 TWh | 2 |
| #12 | Shelby County, IL | 3.4 TWh | 3 |
| #11 | Tazewell County, IL | 3.6 TWh | 17 |
| #10 | Kendall County, IL | 5.4 TWh | 6 |
| #9 | Lee County, IL | 5.6 TWh | 15 |
| #8 | Randolph County, IL | 6.2 TWh | 7 |
| #7 | De Witt County, IL | 9.0 TWh | 5 |
| #6 | St. Clair County, IL | 12.2 TWh | 17 |
| #5 | Rock Island County, IL | 16.4 TWh | 7 |
| #4 | LaSalle County, IL | 19.5 TWh | 28 |
| #3 | Ogle County, IL | 19.7 TWh | 13 |
| #2 | Grundy County, IL | 22.2 TWh | 15 |
| #1 | Will County, IL | 27.2 TWh | 47 |
Net Generation data is based on the last 12 months since Jul 2026