Where Illinois Gets Its Electricity
Net generation by source · 12-month average, September 2025 – August 2026.
Generation mix
| Source | Share | Generation |
|---|---|---|
| Natural gas | 17.3% | 34,003 GWh |
| Coal | 14.9% | 29,215 GWh |
| Nuclear | 49.3% | 96,646 GWh |
| Wind | 13.3% | 26,159 GWh |
| Solar | 4.7% | 9,277 GWh |
| Hydro | 0.0% | 24 GWh |
| Other | 0.4% | 787 GWh |
196.1 TWh generated over the 12 months to August 2026. Shares are of net generation within Illinois, which is not the same as what the state consumes — power crosses state lines.
Counting rooftop solar
EIA reports small-scale solar — mostly rooftop panels on homes and businesses — separately, and leaves it out of the state generation total that the mix above is a share of. Illinois generated 2,780 GWh that way. Counting it on both sides of the ratio takes solar from 4.7% to 6.1%.
How the mix has shifted since 2001
| Source | 2001 | 2025 | Change |
|---|---|---|---|
| Natural gas | 2.6% | 16.8% | +14.3 pts |
| Coal | 44.4% | 16.0% | −28.4 pts |
| Nuclear | 51.5% | 50.5% | −1.0 pts |
| Wind | 0.0% | 12.9% | +12.9 pts |
| Solar | 0.0% | 3.4% | +3.4 pts |
| Hydro | 0.1% | 0.0% | −0.1 pts |
| Other | 1.4% | 0.4% | −1.1 pts |
Compared with the U.S. and nearby states
Illinois's generation mix in context
Nuclear is the largest source of Illinois's electricity generation, supplying 49.3% of the 196.1 TWh total in the year ending August 2026. Natural gas accounts for 17.3%, wind for 13.3%, and coal for 14.9%. Utility-scale solar generates 4.7% of the state's power; counting rooftop solar as well raises the solar share to 6.1%.
Carbon-free sources—renewables and nuclear together—make up 67.5% of Illinois's generation mix, well above the national figure of 43.0%. Renewable generation alone accounts for 18.2%, placing the state 28th among the 50 states and DC. Solar ranks 25th with a share that rises from 4.7% to 6.1% when distributed solar is included.
Since 2001, Illinois's generation mix has shifted substantially. Coal collapsed from 44.4% in 2001 to 16.0% in 2025, while gas rose from 2.6% to 16.8%. Wind emerged to reach 12.9% in 2025, and solar appeared to reach 3.4% in 2025. Nuclear has remained stable, at 51.5% in 2001 and 50.5% in 2025. Renewable generation grew from 0.5% in 2001 to 16.4% in 2025. Among its five bordering states, Iowa and Indiana both have higher renewable shares than Illinois, while Missouri, Wisconsin, and Kentucky have lower shares.
Written from the EIA figures on this page, covering data through August 2026.
Frequently asked questions
›What percentage of Illinois's electricity comes from renewable energy?
›What percentage of Illinois's power comes from solar?
›Where does Illinois get most of its electricity?
›Does Illinois still burn coal for electricity?
›Is Illinois getting greener?
How this is measured
Figures are net generation reported to the U.S. Energy Information Administration for all sectors — utilities, independent power producers, and industrial and commercial plants that generate their own power. Shares are of the 12 months to August 2026, rather than a single month, because generation is strongly seasonal: solar peaks in summer and hydro with the spring melt, so one month says more about the weather than about the grid.
“Other” is the reported total minus the six named sources, so the shares add to exactly 100%. It holds geothermal, biomass, petroleum, other gases, and pumped storage — the last of which consumes more electricity than it returns, and so can be negative. Geothermal and biomass are renewable, which is why the renewable share above is slightly larger than wind, solar and hydro added together.
This is generation, not consumption. Electricity crosses state lines freely, so a state can generate more than it uses or rely on imports for a large part of its supply; neither shows up here.