Data center critics alarmed by ATC’s plans to add $2B+ in transmission infrastructure

American Transmission Company (ATC) is planning to add between $2.63 billion and $2.98 billion in new transmission lines and substations across Wisconsin to support hyperscale data centers. This infrastructure is intended to serve facilities owned by Microsoft in Mount Pleasant, Meta in Beaver Dam, and Vantage in Port Washington, among others in southeastern Wisconsin. However, data center critics and intervenors in tariff cases before the Public Service Commission (PSC), including the Citizens Utility Board (CUB) and Wisconsin Industrial Energy Group, are alarmed by the financial implications. Tom Content, executive director of CUB, argues that the current federal cost-sharing formula would force other ratepayers to cover the initial construction costs, constituting harm. Utilities like We Energies and Alliant, which power these data centers, contend that data center customers will fully cover their related transmission costs. We Energies stated its data center customers will pay $564 million over the next two years for these expenses. PSC staff analysis predicts that We Energies customers could pay an additional $112 million to $117 million for transmission infrastructure by 2028 if data centers do not come online as projected or fail to meet demand. CUB's proposal for data centers to pay directly for infrastructure was deemed impermissible under federal rules by PSC staff. Instead, staff suggested a "minimum billing demand charge" to ensure data centers pay for their forecasted load. We Energies has countered with its own proposal, to be filed with the Federal Energy Regulatory Commission (FERC), which would have We Energies billed for any difference between forecasted and actual data center power draw, then pass those costs to data centers. The PSC is expected to make decisions on the data center contract cases in April, with a separate rate case for We Energies to follow. Content expressed concern that We Energies' latest proposal might delay crucial customer protections until next year, leaving ratepayers vulnerable to higher costs in the interim.