Interstate Power and Light Company (IPL) and Wisconsin Power and Light Company (WPL) are Alliant Energy's two utility subsidiaries. Our utilities provide safe, reliable, affordable and environmentally sound electric and natural gas services to approximately one million electric and 400,000 natural gas customers in the upper Midwest.
| 2011 Statistics | Totals |
| Maximum peak hour demand (megawatts) | 5,734 |
| Number of total electric customers | 986,045 |
| Utility electric sales (thousands of megawatt-hours) | 30,777 |
| Number of total natural gas customers | 414,160 |
| Utility natural gas sold and transported (thousands of dekatherms) | 102,220 |
The utilities own a portfolio of electric generating facilities with a diversified fuel mix including coal, natural gas and renewable resources. The output from these generating facilities is supplemented with purchased power.
In 2011, electric utility operations accounted for 83 percent of total operating revenues and gas utility operations accounted for 15 percent.
