Prometheus's 2.5GW Pecos plan skips the grid, and sits next door to its own fuel

Prometheus Hyperscale and Istmo Energy said they will develop a data center campus of up to 2.5GW in Pecos, Reeves County, Texas, powered behind the meter rather than through a grid connection ^[1][2][3]. Phase 1 is 1.5GW, or 60 percent of the headline number, with first power slated for 2027 ^[2][1][5].

The assembly is worth reading as a template rather than a single deal. Generation sits behind the meter and burns two streams: piped natural gas plus fuel from Istmo Midstream's co-located fractionation facility ^[3]. The companies argue the dual-fuel arrangement reduces dependence on any single fuel source or supply pathway ^[4]. Istmo CEO Alex Gutierrez said pairing behind-the-meter generation with the co-located fractionation assets "insulates compute from grid constraints and curtailments" ^[6]. Delivery is staged the way capacity-constrained developers now stage everything: modular deployments first, with an option to combine those units with custom-built facilities in 2028 ^[5]. The campus is expected to use closed-loop cooling to alleviate local concerns about water use ^[7], which in West Texas is the cheapest objection to pre-empt.

The timing explains the design. Earlier this month Texas governor Abbott ordered state regulators and ERCOT to audit every data center in the state's interconnection queue ^[8]. Prometheus and Istmo contend that because they are not seeking a grid connection, the audit does not touch them ^[9]; the companies put the potential exposure at up to 20 percent of US data center projects facing delay ^[10]. Queue position has become a political variable, not just an engineering one, and building your own power station is now a way to route around regulators as well as around transmission.

Prometheus has run this play before. In June it secured planning approval for a 506-acre campus in Evanston, Wyoming, initially offering 1.25GW with potential expansion to 5GW ^[11]. That site is to operate as a fully islanded microgrid on on-site gas engines and turbines ^[12], which the company said eliminates "interconnection queue exposure and ratepayer impact as regulatory risk factors" ^[13]. It is also planning a 500-acre development in Kaufman County outside Dallas ^[14]. Add the announced first phases and the company is talking about 2.75GW of initial capacity across Wyoming and Pecos, with headline potential of 7.5GW ^[2], from a business that was relaunched in September 2024 ^[15].

One detail does not reconcile. The announcement describes the second fuel as methane from the fractionation facility ^[3], while Gutierrez's own quote describes integrating on-site ethane supply alongside pipeline natural gas ^[6]. Those are different fuels with different handling and different combustion equipment, and the difference is not cosmetic for anyone specifying engines or turbines ^[3].

Three things to watch. Whether the ERCOT audit's scope, once defined, actually leaves behind-the-meter sites alone, since Abbott's order was aimed at the queue and these projects are asserting exemption by structure rather than by ruling ^[8][9]. Whether 2027 first power survives contact with gas turbine and engine lead times, given the same equipment is being ordered by every islanded campus making the same bet ^[5][12]. And whether the fuel spec resolves to methane, ethane or both, because a fractionation plant next door is the differentiator here, and the value of that adjacency depends entirely on what comes out of it and how continuously ^[3][6].