Powerstack: Lost in Transmission at Stargate Wisconsin

Wisconsin’s utility regulators just revoked the certification for the transmission line connecting the Midwestern Stargate data center to the grid. The developer now has to refile, pushing back the timeline by at least eight months, even though construction is underway. We unpack all the bureaucracy and the lessons below.

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What happened

Wisconsin's Public Service Commission voted 3-0 to rescind its “completeness determination” for the transmission line built to serve the Stargate data center north of Milwaukee. The American Transmission Co (ATC), which builds power lines for its parent utilities, will now have to restart a year-long certification process. Commissioners blamed the more than 550 project amendments since December, saying the application wasn't ready for coherent public review, but ATC is pushing back.

The project is a high-voltage line and new substations designed to connect data center developer Vantage's Lighthouse campus (the Midwest site in the OpenAI and Oracle Stargate program in Port Washington) to the grid. At a projected cost of $1.39bn to $1.67bn, it covered 88 to 104 miles of new and updated 345kV and 138kV line depending on route, 40 miles of uprate work, and four to five new substations across six counties. It serves only the first of four planned buildings on the campus, and Phase 2 sits in a separate proceeding. 

It’s another headache for ATC as it tries to build Lighthouse, part of the Stargate initiative. The campus is already under construction, but these transmission troubles pose a huge risk to the project's timing. ATC had submitted an original application in September 2025, the PSC found it incomplete, and ATC refiled in November. Then, over the next six months, it filed 564 application documents and 168 staff data request responses, proposing changes to routes, costs, and environmental studies across scattered filings. Administrative Law Judge Michael Newmark ordered ATC to consolidate and redline everything by July 10, citing due process: the filing pattern put an unreasonable burden on staff and intervenors and impeded environmental review. 

Opponents pushed on two fronts. The Responsible Energy Alliance argued ATC never justified routing new 345kV circuits through greenfield farmland in Ozaukee and Washington counties rather than using existing utility corridors, as state law prioritizes. Vantage's own witness supported the southern alternate route, which would have used existing infrastructure.

But ATC fought back hard and on real legal ground. It said that the commission had itself concluded in a 2022 solar docket that revoking completeness "is not procedurally available," and that the law says the commission has only 30 days to find an application incomplete, after which completeness attaches by operation of law. It also argued the 564 figure is inflated, mostly reflecting single documents split to clear file-size limits on the filing system, and that redlining GIS maps and spreadsheets was impossible as ordered. ATC offered schedule extensions instead, but the commission went the other way. 

Mark’s take

Alright, called it. Kind of.

Back in April we did a Powerstack on how a small-but-mighty clerical error put an end to Prince William County's Digital Gateway. We said it wouldn’t be the last time in this era of speed-to-power that a project met its match in the bureaucracy.

While the Digital Gateway example was entirely procedural, this one in Wisconsin is more structural. ATC kept changing the application, and the regulator didn’t have the tools to deal with it.

A lawyer friend once told me that when you propose a transmission line, you always propose two routes. A is the one that surely gets rejected. B is the one you actually wanted all along. ATC did this, it proposed two, and spent eight months fighting for A. But oddly, its own customer testified that it supported B. The state agriculture department recommended B. Both counties and four towns wanted B. And Wisconsin statute puts B first by law (as it was along an existing line, instead of greenfield build). ATC seems to not subscribe to the A/B strategy. 

This wasn’t the undoing, though. Silicon Valley is used to building software where requirements change, you experiment, you iterate. You preserve optionality. But this operating model doesn’t really work when it meets regulation that wants a fixed object to review. My take is that ATC filed those 564 documents because the load it will serve keeps getting re-forecast, so the project kept moving. I saw articles that were saying this was sloppiness on the part of ATC. I don’t think it was. The pushing A while everyone was all for B might have been sloppy, but really the challenge was that the changes made it near-impossible for the PSC to adequately assess the project – and measure the impact for ratepayers.

So how do you allow for change? How much change to an application is too much? Right now, no one knows. There’s no siting or permit program I know of that lists how much an application can materially change after it has been submitted and found complete. Both sides of this power boom – the builders and the regulators – are figuring it out as they go. So when a project breaches an unseen but understood boundary, commissions improvise. Wisconsin doubled back on its own 2022 precedent with this decision, and its judge had to invent a change-log requirement on the fly, with a nine-day deadline. Again, I’m not sure either side was at fault here, but the system is not set up for any sort of flex.

A way to get past this is to not make it flexible, but to firm it up – the regulator publishes the threshold. How much change to an application is too much. Require the change log from day one. And enough of the A/B dance – applicants just go for the one preferred route to get expedited review.

Looking back up at the Currence platform screenshot – our estimated regional average time to power is 54 months. ATC just used eight to get back to square one.

Who this helps:

Who should be nervous:

A quick read on the numbers shaping the market. The capex, the contracts, the regs, all anchored in the so-what.

$1.22bn // RWE’s buyout for its US offshore wind leases off NY, CA, and LA. It joins five developers that have taken similar deals to hand back federal offshore wind leases and redirect the reimbursed capital toward fossil and other Trump-favored investments. More than 20 leases worth nearly $2bn remain outstanding, meaning more agreements are likely in the coming months.

7.65GW // Amazon filed to build its own 7.65GW gas-fired power complex in Texas. Filings reveal 35 turbines, 1.8GW of batteries, 750MWac of solar, all wired to a single AWS campus that never touches ERCOT. It seems like a direct response to Gov. Abbott's interconnection freeze: if the state won't let you connect fast enough, don't ask.

15% // The White House imposed a 15% tariff plus import price floor on polysilicon and its downstream products (wafers, cells, panels) under Section 232, effective 4 Dec 2026, aimed at protecting domestic producers. It helps First Solar, the only US-scale panel manufacturer, but domestic wafer and cell capacity doesn't exist at the scale needed to fill the gap, so procurement could get pricier.

+$220m // TVA's net income bump in fiscal 2026 so far, from data center power. Data processing and web hosting demand is now 18% of TVA's industrial load and projected to double by 2030. For a federal utility that can't raise equity the way AEP or Duke can, data center revenue isn't just growth optionality -- it's becoming the primary lever TVA has to fund its planned 6.2GW of new gas and nuclear capacity without leaning harder on Valley ratepayers.

$980m // LDES raises this week from Form Energy and Hydrostor. Form Energy, the iron-air battery developer, closed a $750m Series G, with agreements up from ~20 GWh to 80 GWh this year, anchored by the Xcel/Google deal plus new agreements with Crusoe and FuturEnergy Ireland. Hydrostor, a compressed air energy storage developer, closed $230m to advance its pipeline, including the 500MW Willow Rock project in California, as multi-day storage accelerates.

Explore more Signals on Currence here.

The policies, rulings, and company moves worth watching.

ERCOT's Batch Zero notification slipping. The grid operator was set to classify all 326 applicants, roughly 205GW of large-load interconnection requests, by August 7, but Gov. Abbott's August 3 directive to audit data center requests pushed that date with no replacement confirmed. 

DOE scrapped three Biden-era National Interest Electric Transmission Corridors. Secretary Wright announced that the Lake Erie-Canada, Southwestern Grid Connector, and Tribal Energy Access corridors won't advance, corridors that would have unlocked federal financing and permitting support for transmission in congested areas.

Grid operators face a Sunday deadline to rewrite large-load interconnection rules. FERC's June 18 Section 206 orders gave PJM, MISO, SPP, CAISO, ISO-NE, and NYISO 60 days to justify their existing tariffs for large loads or file revisions, so on August 17. The responses will shape how data centers interconnect across two-thirds of US electricity demand if they file on time.

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