A planned artificial-intelligence campus at the former Portsmouth uranium-enrichment site in Ohio is so large that calling it a data-centre project hides most of the engineering. The public plan joins a 10-gigawatt computing campus to 10 gigawatts of new generation, at least 9.2 gigawatts of it natural gas, plus a new pipeline, high-voltage transmission and substations. Each layer has its own construction schedule, approvals and failure modes.[1][2]
The number is difficult to picture. Ten gigawatts is a power level, not an annual energy forecast. If a 10-gigawatt load ran at that level for every hour of a non-leap year, it would consume 87.6 terawatt-hours. The same arithmetic puts 9.2 gigawatts of gas generation at 80.6 terawatt-hours if it ran continuously. Neither result predicts utilisation, outages or dispatch; both show why this cannot be evaluated as one building with a large electricity bill.
Portsmouth’s linked infrastructure plan
| Measure | Value | Context |
|---|---|---|
| Planned data-centre development | 10 GW | The announced maximum campus scale; not evidence that all capacity will arrive at once.Source 1 |
| Planned new generation | 10 GW | At least 9.2 GW is described as natural-gas generation.Source 1Source 2 |
| Transmission investment | $4.2 billion | SB Energy has committed to fund the planned AEP Ohio work, subject to approvals.Source 1Source 3 |
| High-voltage build | New 765 kV lines and four substations | The electrical path is part of the project, not an invisible utility service.Source 1 |
| Expected first power | 2029 | AEP Ohio’s stated expectation, not a guarantee of full campus completion.Source 3 |
The critical path is the slowest connected system
A server hall can be commissioned only when several other systems are ready: a firm site, cooling and water arrangements, electrical equipment, fuel delivery, generation, transmission, networking and enough compute hardware. A delay in one can strand investment in the others. That makes the sequencing more important than a single headline completion date.
The Portsmouth fact sheet says long-lead electrical equipment has already been secured and describes 765-kilovolt lines and four substations. AEP says power is expected to begin flowing in 2029. Those statements narrow one part of the schedule, but they do not establish that all 10 gigawatts of generation, transmission and compute will be available in 2029. Serious progress reporting should publish capacity by phase rather than repeat the ultimate target.[1][3]
What a useful progress dashboard would separate
| Layer | Question that matters | Evidence of readiness |
|---|---|---|
| Compute | How much IT load can operate? | Commissioned megawatts, tested racks and cooling capacitySource 1 |
| Generation | How much power can run when required? | Commercial-operation dates, fuel contracts and tested outputSource 2 |
| Grid | Can power move safely in both directions? | Energised lines, substations, interconnection rights and operating limitsSource 3 |
| Site and cleanup | Which land is actually available? | Lease milestones, remediation boundaries and permitsSource 4Source 1 |
“Excess capacity” needs an operating definition
The parties say excess generation and transmission capacity will be made available to the grid and that the developer will fund the new transmission. That commitment matters, but the public value depends on operating details: when capacity is excess, whether it is firm during peak conditions, which fuel and transmission constraints apply, and how costs and revenues are allocated. A nominal surplus at one hour is not the same as dependable capacity during a regional shortage.[1][3]
The IEA expects global data-centre demand to rise rapidly while emphasising substantial uncertainty in AI uptake, efficiency and energy-system bottlenecks. Portsmouth illustrates that uncertainty in physical form. A very large final target may be plausible while the delivered capacity curve remains staged, conditional and vulnerable to long lead times.[5]
The project is consequential precisely because it is more than a data centre. Its success will be measured not by the biggest number in the announcement, but by whether power plants, pipelines, transmission, substations, cleanup and computing capacity arrive in a coherent sequence—and whether the promised separation between project costs and ordinary customer bills survives real operation.
Sources & further reading
- FACT SHEET: The Department of Energy is Ensuring Affordable Energy Access in Ohio While Powering the Future of AI U.S. Department of Energy · 20 Mar 2026 · Accessed 8 Oct 2026
- Energy Department Announces Partnership to Ensure Affordable Energy and Power America’s AI Future U.S. Department of Energy · 20 Mar 2026 · Accessed 8 Oct 2026
- AEP Ohio Partners to Bring $4.2B in New Electric Infrastructure in Appalachian Ohio Without Raising Customer Rates AEP · 20 Mar 2026 · Accessed 8 Oct 2026
- Portsmouth Site U.S. Department of Energy · Accessed 8 Oct 2026
- Key Questions on Energy and AI International Energy Agency · 16 Apr 2026 · Accessed 8 Oct 2026