A generator fleet built to stay under the radar
Amazon's data center complex in Hamlet, North Carolina, part of Richmond County, has become the target of a formal environmental complaint over how it is permitting its backup power. The Southern Environmental Law Center says Amazon and Duke Energy are operating a combined 649 diesel generators at the site, 592 owned directly by Amazon and 57 by Duke, and alleges the fleet has been split into smaller individual units specifically to avoid tripping Clean Air Act major-source permitting requirements that would apply to a single larger installation.
The site itself is a substantial project by any measure. Amazon broke ground in October 2025 on what has been described as a $10 billion complex, with plans for up to 20 buildings, each spanning more than 200,000 square feet at full build-out. A fleet of nearly 650 diesel generators for backup power fits a campus of that footprint in absolute terms. SELC's argument centers specifically on how the units were sized and grouped, alleging the configuration was chosen deliberately to fall under thresholds that would otherwise require stricter federal review of the facility as a whole.
The permitting math regulators care about
Clean Air Act major-source permitting kicks in based on aggregate potential emissions from a facility, and diesel generators, even backup ones that rarely run, count toward that total calculation under federal rules. Developers who split large power needs into many smaller units can, in some circumstances, stay under a threshold that would otherwise apply to a single large emitter, a practice regulators and environmental groups have flagged before at industrial sites and are now applying scrutiny to across the fast-growing data center sector, as campuses scale into hundreds of megawatts of backup capacity apiece and hundreds of individual generator units on a single parcel.
SELC senior attorney Caroline Cress put the criticism bluntly: "One of the wealthiest companies in the world can and should do better than trying to evade critical air quality protections." The complaint does not allege the generators are currently violating limits, it alleges the permitting structure itself was designed to avoid a stricter review process that would otherwise apply to a facility of this scale, arguing regulators should evaluate the campus as a single major source rather than as hundreds of individually permitted small units spread across the property.
Duke Energy's parallel expansion
Across the street from the data center site sits Duke Energy's Smith Energy Complex, a 1.247GW gas plant built in 2001. Duke has separate plans to add 240MW of capacity at Smith specifically to serve the growing data center load in the area, with construction expected to begin in late 2027 and the expansion coming online in late 2029. That timeline gap, roughly four years between groundbreaking on the data center and new firm generation arriving, is exactly why backup diesel fleets have become so central to how these campuses operate in their early years.
This is the underlying tension regulators are grappling with nationwide: data centers need to be online long before new gas or renewable generation can be permitted and built, so developers lean heavily on diesel backup to bridge the gap. The Hamlet complaint is really a proxy fight over that gap, and how much diesel capacity a developer can deploy in the interim without triggering the same environmental review that a new gas plant would face.
Why this matters beyond one North Carolina site
Backup diesel fleets in the hundreds of units are becoming standard at gigawatt-scale AI campuses, and Hamlet is unlikely to be the last site where this exact permitting structure gets challenged in court or before a state regulator. Environmental groups have already flagged similar patterns at other hyperscale sites around the country, and a successful complaint against Amazon, one of the best-resourced and most experienced developers in the industry, would set a precedent that other operators would need to account for in their own permitting strategy going forward.
For enterprise customers, the practical risk is indirect but still real: campuses facing active environmental litigation or stricter re-permitting requirements can see construction delays, which can push back committed capacity delivery dates by months or longer. If your organization has reserved capacity tied to a site still ramping up its own generation, backup power disputes like this one are worth tracking as a leading indicator of schedule risk, not just a regulatory footnote buried in a local news story.
What to watch next
Watch whether SELC escalates this into formal litigation or a regulatory petition to North Carolina's environmental agency, and whether Amazon responds by consolidating or re-permitting the generator fleet voluntarily. Amazon has generally avoided public confrontation on these issues at other sites, and has tended to make quiet compliance adjustments to settle disputes before they escalate into prolonged legal fights that draw sustained media and regulatory scrutiny to a broader portfolio of sites.
More broadly, expect diesel backup permitting to become a standard line item in how environmental groups evaluate new hyperscale announcements, alongside water use and transmission impact assessments. As AI campuses scale past a gigawatt and diesel fleets scale into the hundreds of generators per site, the Clean Air Act's major-source thresholds, written for a very different era of industrial facilities decades ago, are going to keep getting tested by developers racing to bring capacity online faster than permitting was ever designed to accommodate.
