North Carolina’s Republican-controlled Utilities Commission has rejected Duke Energy’s request to build a $500 million natural-gas plant intended primarily to serve Amazon’s data-center campus in Richmond County. The five-member commission voted Friday against the proposed 250-megawatt peaker plant at Duke’s Smith Energy Complex in south-central North Carolina. The site already has five generating units. Republican commissioners William Brawley, Tommy Tucker and Donald van der Vaart said Duke had not adequately explained how it would prevent ordinary electricity customers from paying for the facility. They specifically cited President Donald Trump’s voluntary Ratepayer Protection Pledge, which calls on utilities to ensure that technology companies cover the costs of new generation and grid upgrades needed for data centers. Duke is among hundreds of utilities that have signed the pledge. The commissioners said the utility’s application did not demonstrate that the proposed plant would comply with its commitments under the agreement. They also said Duke had not sufficiently evaluated alternatives, including battery storage, or established that the plant was needed before the commission completes its broader energy planning process this winter. The rejection is not final. Duke can submit a new application with different cost-recovery provisions and additional evidence. “We believe we have demonstrated that the [project] is part of a least-cost path to maintain reliable and affordable service for customers as energy demand continues to grow across North Carolina,” Duke spokesperson Craig Wilson said in an email. He said the utility was disappointed and would evaluate its next steps. Amazon did not provide a response. The ruling comes as regulators and communities across the country grapple with the rapidly rising electricity demand associated with artificial intelligence and hyperscale data centers. The Amazon campus near Charlotte is planned to include 21 buildings and is expected to be completed in 2029 or 2030. The company broke ground last year on the project, which has been valued at about $10 billion. For now, Amazon has received state environmental permits to operate 57 temporary, non-emergency diesel generators for up to a year while the facility connects to the electric grid. A separate permit allows nearly 600 diesel backup generators, bringing the potential total to 649 diesel-fired generators. Those permits have drawn strong opposition in Hamlet, a small Richmond County town already dealing with industrial air pollution. Nearly 200 people attended a contentious public hearing in July, where residents raised concerns about additional fine-particle pollution, which has been linked to serious health risks, including cancer. “Amazon, one of the wealthiest companies in the world, and Duke Energy, a regulated monopoly, can and should do better than belching deadly soot pollution into the air North Carolinians breathe from a whopping 649 diesel-fired generators powering a massive data center,” Caroline Cress, a senior attorney with the Southern Environmental Law Center, said in a statement. Commission staff said the panel has rejected only one other Duke natural-gas project in roughly the past 35 years. The commission approved two combined-cycle gas plants about a decade ago but rejected a third combustion-turbine proposal. Commissioner Floyd McKissick, one of two Democrats on the panel, objected to the decision’s procedural basis. The other Democratic commissioner was absent. McKissick noted that Trump’s ratepayer pledge is not legally binding. Will Scott, North Carolina policy director for the Environmental Defense Fund, said the ruling’s language about avoiding “stranded assets”—expensive infrastructure that may no longer be needed—was unusually forceful. He said the commission is developing a large-load tariff that could assign data-center electricity costs directly to operators, but under current arrangements, ratepayers could still bear costs associated with the proposed gas plant. Tucker said the commission needed more evidence that the plant would be necessary and economically justified, given its price and the possibility that it could become a stranded asset.