Pennsylvania issues large-load tariff model

The Pennsylvania Public Utility Commission on May 13 released a final model tariff framework for large-load customers, including data centers and other high-demand users. The commission said the framework is designed to manage rapid electricity demand growth while protecting existing ratepayers. A central provision tells utilities to assign upgrade costs to a customer when the infrastructure “would not have been needed ‘but for’” that customer’s interconnection. The model tariff is nonbinding, but the commission said it is intended to guide future utility filings across the state. ### What, exactly, did Pennsylvania regulators put out? The PUC’s action was a final order establishing what it called a “first-of-its-kind” model tariff framework for large-load customers. Chairman Steve DeFrank said in the commission’s May 13 release that the issue is “one of the most important infrastructure and consumer protection issues facing utility regulators across the country.” The framework addresses customers such as data centers as Pennsylvania utilities confront rising demand and questions over who pays for new system investments. (puc.pa.gov) The April 30 public meeting was the formal vote that adopted the framework, and the written final order followed on May 13. The process grew out of a March 2025 commission motion and an April 24, 2025 en banc hearing that included utilities, large-load customers, and consumer advocates. Participants listed by the commission included Amazon Data Services, Google, Vantage Data Centers, Duquesne Light, FirstEnergy Pennsylvania, PECO Energy and PPL Electric. (puc.pa.gov) ### How does the “but for” rule work? The most closely watched language in the order says utilities should charge large-load customers for system upgrades that “would not have been needed ‘but for’ the interconnection” of that customer. The PUC said that standard applies “irrespective of whether other customers will benefit” from the infrastructure later. Utility Dive described that provision as a notable feature of the order because it places the triggering customer at the center of cost responsibility. (puc.pa.gov) Daily Energy Insider reported that the framework also authorizes customer self-construction in some circumstances. The order, as summarized by EnergyChoiceMatters, did not adopt a requirement that large-load customers bring their own generation, despite comments on that issue during the proceeding. (utilitydive.com) ### Why were data centers so prominent in this proceeding? Harrisburg-based regulators tied the framework directly to “rapidly expanding data centers” and broader large-load growth. The commission said the order responds to “unprecedented electricity demand growth” and is meant to protect existing customers from bearing costs associated with new high-demand connections. Regional coverage in the Times Leader and other Pennsylvania outlets also framed the order around data-center expansion. (dailyenergyinsider.com) The November 24, 2025 notice opening comment on the tentative order said the model tariff would cover data centers and other high-demand electric users. A separate Nov. 6, 2025 PUC release said the tentative order aimed to ensure new users “pay their fair share.” ### What does this change for project owners and contractors? (puc.pa.gov) The May 13 order does not set a statewide fixed price for upgrades, but it gives utilities a template for assigning those costs in future tariff filings. Because the standard turns on whether a project is the reason an upgrade is needed, customers seeking service will have a stronger incentive to pin down interconnection scope, timing and cost responsibility before construction advances. That inference follows from the order’s cost-allocation language and from the commission’s focus on transparent cost structures for interconnection. (puc.pa.gov) The framework also matters because it is nonbinding. Pennsylvania utilities still must translate the model into company-specific filings, and those filings can be contested before the commission. That means the next practical test will come in individual tariff cases rather than in the model order itself. ### What happens next, and where will the next fight be? (utilitydive.com) The PUC said the model tariff is intended to guide electric distribution companies as they develop large-load tariff provisions. Company filings before the commission will determine how the framework is applied in practice, including the treatment of upgrade costs, ramp schedules, exit fees and firm versus interruptible service. Those elements were all identified by the commission during the en banc process and in materials tied to Docket No. (puc.pa.gov) M-2025-3054271. (puc.pa.gov)