Alliant Energy, the Wisconsin-based utility serving customers in Iowa and Wisconsin, said on 29 and 30 October that it expects to sign about one gigawatt of additional data center demand within the next six months. It already has 3.4 GW under contract with large customers, and it lifted its capital spending plan for 2027 to 2030 by 19% to $15.9 billion.
What is signed and what is only expected
According to the company's results release of 29 October, the 3.4 GW sits across its two electric utilities, and peak demand on the system is expected to rise by about 60% by 2031. Reuters, reporting on the call a day later, names Google, Meta and QTS Data Centers among the customers. The extra gigawatt is a prospect, not a contract: Alliant's finance chief described it as an upside to the capital plan, and the load is expected to begin ramping between 2029 and 2031. One customer is due to start taking transmission service in Wisconsin in the first quarter of 2027.
The spending plan names renewables and storage as well as thermal generation and liquefied natural gas as separate lines, so the utility is not building for this load with one technology. Earnings guidance for 2026 was narrowed, and the dividend target for 2027 was set higher than the current one.
Years between a signed contract and a running load
A date of 2029 for the first of the new load tells you how a utility sees it: this is plant that has to be planned, permitted and built, and the customer's own building will usually be ready sooner than the supply. That gap is where on-site power and backup plant come in. We saw the same pattern when utilities described their load planning and in the Kentucky project we covered in the Mason County item.
For the people who specify standby generation, the practical question is how long a campus must live with temporary or bridging supply, because a set that is meant to run a few hours a year is a different job from one that carries a site for months. Ask early which one the project means, and what the permit will say about it.
Sources: Alliant Energy results release (SEC filing), Reuters via The Star