Prometheus and Istmo plan a grid-free Texas data campus

Prometheus Hyperscale and Istmo Energy are planning a data center campus in Reeves County, Texas, that will run on its own power. The Pecos project, as it's called, begins at 1.5 gigawatts and can grow to 2.5, leaving the grid out entirely.

Generators will burn a dual fuel supply: pipeline natural gas and methane from Istmo Midstream's fractionation plant on the same site. The companies say that arrangement removes the single-path failure risk of a pipeline-only setup. First power is slated for 2027 via modular data halls, with custom-built capacity possible in 2028. Closed-loop cooling will be used on-site, a concession to the area's water constraints.

The off-grid structure is a deliberate answer to Texas's overloaded interconnection queue. Governor Greg Abbott earlier this month ordered state regulators and ERCOT to audit every data center in that queue. Prometheus and Istmo say Pecos will sidestep the review because it will never ask for a connection. Data Center Dynamics, which first reported the partnership, says the audit could put a fifth of U.S. data center projects at risk of delay.

Prometheus has spent its short life turning that approach into a template. It started in 2020 as Wyoming Hyperscale Whitebox and renamed itself Prometheus in September 2024. In June it won approval for a campus outside Evanston, Wyoming, on 506 acres. That project, designed to start at 1.25 gigawatts and possibly reach five, will be a fully islanded microgrid: on-site natural gas engines and turbines, no utility connection.

The company's ambition is a string of carbon-neutral data centers. The Texas project adds 2.5 gigawatts to that pipeline, said Prometheus president Trevor Neilson. Istmo CEO Alex Gutierrez called the fuel arrangement a step change: "Seamlessly integrating on-site ethane supply alongside pipeline natural gas eliminates single-point fuel risks, insulates compute from grid constraints and curtailments, and establishes a new benchmark for uptime and operational resilience in hyperscale infrastructure."

The announcement leaves a puzzle in place: how a gas-fired campus fits a carbon-neutral pledge. The release offers no capture, offset, or credit mechanism. And the "unprecedented" and "benchmark" language is the developers' own; the public record includes no independent study to measure it against.

Istmo is not a distant fuel supplier. Its fractionation plant sits on the same plot, giving the project two gas paths — the pipeline and the plant next door. Generation is on-site, and the tenant's economics depend on uptime. That combination yields an off-take story no grid-connected rival can match: no queue at all.

The design carries costs. It runs on fossil gas, with no stated plan for emissions, and fuel prices can move against it. It also buys something the Texas grid cannot guarantee right now: firm power, on demand, with no one else waiting in line. The Pecos project wagers that AI builders are short of firm power, not a slot in the queue. The state's audit is making that wager easier to understand.