Writing

Data centers in Wisconsin

Facility data as of 22 September 2026

Wisconsin is building at a scale that makes it the more interesting of the two states we cover, and the arguments here are further along than Minnesota's: the tax break is already law and already costing, the utility rate case is already decided, and the biggest operator has already filed its water numbers. So this page does what the coverage mostly does not: it takes those filed figures and converts them into something comparable, using the same calculators as the rest of the site.

The cooling design sets water use for that same planned load. Cooled evaporatively it would consume up to 10,989 million gallons a year; closed-loop, up to 343 million. The cooling estimator works the trade, because the designs that drink least burn most.

Every site on record

Sorted by status, then by size. "Disclosed capacity" is what the operator or a public record has actually stated. A blank means no figure has been published; it does not mean zero. Facility names link to the primary source. Power stations are excluded: see the note on generation below.

Two projects are most of the story

Wisconsin's list has a very long tail of small colocation sites and two enormous campuses that dominate every total on this page. Microsoft's Mount Pleasant campus, on the land assembled for Foxconn, is recorded at 1,000 MW at full build. The Stargate Lighthouse campus at Port Washington is recorded at 902 MW and under construction. Meta's Beaver Dam campus adds 220 MW.

That concentration matters when reading any statewide figure, including ours. Wisconsin data centers are not really one industry: they are three enormous projects and a long tail of small rooms, and an average across the table would describe none of them. It is also why the disclosed operating number on this page is so much smaller than the planned one: the large campuses have published a full-build capacity and not a current draw.

The water question, answered by the operator's own filing

Wisconsin has a water argument that no other state has in quite this form, because Mount Pleasant sits in the Lake Michigan basin and is served by Racine, which holds a Great Lakes Compact diversion approved in 2018 for up to 7 million gallons a day: granted under the "straddling community" exception, originally for Foxconn. Any large water user arriving on that land arrives into an existing and contested permission.

Against that backdrop, the numbers Racine released for Microsoft's campus are strikingly small:

Put 8.4 million gallons a year against 1,000 MW of capacity and the implied water usage effectiveness lands around 0.004 L/kWh, and even on pessimistic assumptions about how much of that capacity is IT load and how hard it runs, it stays inside the 0.01–0.05 band this site uses for closed-loop cooling. That is not an inference anyone has to make, either: Microsoft has said most of the campus uses "a new closed-loop system design that will consume zero water for cooling".

The water figure and the electricity figure point in opposite directions, and only one of them is the real constraint here. For scale, Minnesota's pre-application water review triggers at 100 million gallons a year. Microsoft's Mount Pleasant campus (around a gigawatt, among the largest in the country) discloses about 8% of that, while a 30 MW evaporatively-cooled site next door would trip the threshold outright. Closed-loop cooling buys that reduction by spending electricity instead, which is precisely why the fight in Wisconsin is about the grid and the bill. The cooling estimator shows the trade at any load.

The tax break, and what it has cost so far

Wisconsin exempted data centers from sales tax in the 2023–25 state budget, passed by the Republican-controlled Legislature and signed by Governor Evers. The exemption covers purchases for constructing and equipping a qualifying facility: state and local sales tax both, and it applies to the Mount Pleasant, Port Washington and Beaver Dam projects.

• $40 million in sales tax actually forgone in the last fiscal year, ahead of the Department of Revenue's own projections.
• $1.5 billion estimated forgone during construction, which runs for years.
• $369 million a year estimated once the facilities are operating.

Note what is and is not being claimed there. That is revenue the state chose not to collect, not money paid out, and whether it was worth it turns on activity that would not otherwise have happened here, which is exactly the quantity nobody can measure. The figures above are worth quoting because they are audited; the counterfactual around them is not.

The grid, and the power stations in the dataset

Data centers in Mount Pleasant and Port Washington could roughly double We Energies' demand by 2030, and the utility is planning about $19.3 billion of new generation over five years. In April 2026 the Public Service Commission approved a Very Large Customer tariff for loads of this size, but rewrote it first: extending the minimum initial term to 15 years specifically to stop costs shifting onto everyone else's bill if a campus arrives, triggers construction and then leaves.

That is also why the source dataset contains six power stations in Wisconsin: Point Beach, Oak Creek, West Riverside, Nemadji Trail and others, about 3,690 MW between them. They are tracked because this buildout is now driving generation decisions directly. They are excluded from the table and from every total on this page, because a nuclear plant is not a data center and counting it as one would inflate the state's figures by more than the data centers themselves.

Where this data comes from, and what it is not

The facility list, statuses and capacities are from Compute Atlas, an open, source-cited survey of the US compute buildout, used here under CC BY 4.0 and cited as doi:10.5281/zenodo.22284476. We did not compile it and we do not claim it. Sites marked reported rest on secondary reporting; the operator or a public record has not confirmed them.

The energy, household and water figures are ours, derived from disclosed capacity as described on the power calculator. They are conversions of somebody else's number and inherit whatever is wrong with it, and an announced capacity is a ceiling, not a forecast. Several sites on this list are cancelled, and they were announced with the same confidence as the ones still standing.

Sources

• Compute Atlas: Wisconsin (CC BY 4.0), facility list, statuses and capacities
• WPR, Racine's released records on Microsoft's projected water use
• Wisconsin DNR, the City of Racine Great Lakes Compact diversion
• Public Service Commission of Wisconsin, the We Energies data center tariff decision
• WPR, the cost of the sales tax exemption
• Data centers in Minnesota: the same treatment for the neighbouring state