Digital Realty Seeks Permit for 242 Diesel Generators at Charlotte Hyperscale Data Center

A proposed air quality permit in Mecklenburg County would allow Digital Realty to install and operate 242 diesel-powered generators at its hyperscale data center on Moores Chapel Road in Charlotte, North Carolina, providing backup power during grid outages. The generators would have a combined capacity of 726 megawatts, a scale that rivals some utility-scale power plants and underscores the enormous electricity demands of modern hyperscale computing facilities.

The project predates Charlotte's moratorium on new data centers. The Charlotte City Council approved the data center before the city enacted the moratorium, and Digital Realty purchased the land two years ago. The council approved the company's rezoning request last year with little fanfare, with only Councilmember LaWana Mayfield voting in opposition. Because the project was already underway, it falls outside the scope of the moratorium, which applies only to new data center proposals.

Under the proposed permit, the diesel generators would be authorized to emit more than 100 tons of air pollution annually, including smog-forming pollutants, carbon monoxide and other hazardous air pollutants. The scale of the emissions has drawn attention from regulators, who have yet to make a decision on whether to grant the permit.

The case highlights a growing tension between the rapid expansion of hyperscale data center capacity and local environmental and power infrastructure constraints. As operators seek to guarantee reliability for mission-critical workloads, diesel backup generation remains a common solution, but the associated emissions and the sheer magnitude of on-site power capacity are increasingly subject to regulatory scrutiny. How Mecklenburg County regulators rule on the permit could set a precedent for how similar backup power installations are evaluated in other markets facing data center booms.