Nuclear power for AI data centres: restarts, uprates, new reactors

Technology companies are signing long contracts for nuclear power to run AI data centres. The deals fall into three types: keeping old plants running, restarting closed ones, and funding new reactors. Only the first two supply electricity this decade, and restart dates have already slipped. New reactor designs are targeted for the early 2030s.

This post walks through the main deals, explains each term the first time it appears, and marks what is confirmed, what is a company target, and what remains unverified. Every figure is labelled with its source and date, as of 19 October 2026. Nothing here is investment advice.

Key numbers at a glance

• Microsoft and Constellation, 20 September 2024: 20 year power purchase agreement tied to restarting the Crane Clean Energy Center, about 835 MW (company statement).
• Crane restart: company said online in 2028 in the 2024 release; on 28 September 2026 Constellation said it was "on track" to return 835 MW to the grid in 2027, per World Nuclear News (company target).
• Talen and Amazon, 11 June 2025: 1,920 MW from the Susquehanna plant, through 2042, full volume no later than 2032 (company statement).
• Meta and Constellation, 2025: 20 year extension of the Clinton, Illinois plant (company statement).
• Meta announcement, 9 January 2026: agreements with Vistra, TerraPower and Oklo, which together with Constellation support up to 6.6 GW by 2035 (company statement).
• Meta and Vistra: more than 2.1 GW from two Ohio plants under 20 year agreements, plus 433 MW of uprates across three plants, early 2030s (company statement).
• Meta and TerraPower: up to 690 MW from two units as early as 2032, rights to up to 2.1 GW more targeted for 2035 (company statement).
• Meta and Oklo: up to 1.2 GW campus in Pike County, Ohio, as early as 2030 (company statement).
• Google and NextEra, announced 27 October 2025: Duane Arnold restart, 621.9 MWe, 25 year agreement, now targeted for early 2029 (company statement, reported by ANS).
• DOE loan to NextEra for Duane Arnold: about $1.9 billion, 8 September 2026 (reported by Exchange Monitor).
• Palisades: 800 MWe, $1.52 billion DOE loan guarantee finalised September 2024; Holtec's February 2026 grid target missed; fuel loading paused after a fuel assembly tipped, and the NRC approved a removal plan, reported by Michigan Public on 14 October 2026 (company and reported).
• PJM 2028/2029 capacity auction, 14 July 2026: nuclear made up 20 percent of cleared and committed capacity, behind natural gas at 46 percent (grid operator).
• Palisades site, new build: two SMR-300 units adding about 600 MWe at the site, grid target 2030 (company plan).

The vocabulary, in plain words

A power purchase agreement (PPA) is a long contract in which a buyer agrees to pay for electricity from a specific source at agreed terms. For a data centre company it gives the plant owner a steady income, which helps justify keeping or rebuilding the plant.

A restart means bringing a closed reactor back into service. This is rare. Holtec says Palisades is the first US plant to move from decommissioning back to operations, according to Latitude Media's September 2025 report.

An uprate means getting more output from an existing reactor, for example by replacing turbine parts or tuning the measurements that limit power. It adds megawatts without a new site.

A life extension or licence renewal lets a plant run longer than its original licence term.

Advanced reactors and small modular reactors (SMRs) are new designs, smaller than the large units built in the twentieth century. None of those named below had delivered power to a customer under the deals described here as of 19 October 2026, according to the company statements and trade reports cited.

Front of the meter means the plant sells into the public grid and the customer buys through the grid. Behind the meter or co-located means the plant connects directly to the customer's site. The difference matters for regulation and for who pays for the wires.

Deals that keep existing plants running

The simplest nuclear deal for AI is a contract that stops an existing plant closing.

Susquehanna, Pennsylvania. Talen Energy announced on 11 June 2025 a PPA with Amazon for up to 1.92 GW from the Susquehanna nuclear plant. The term runs through 2042 with options to extend, and volumes ramp up over time with the full amount expected no later than 2032. The release gives no price. It also says the two companies will explore building SMRs in Talen's Pennsylvania footprint and pursuing uprates, but describes these as exploratory, not committed.

The structure matters. The release says an existing co-located arrangement will move to a front of the meter structure after transmission reconfigurations expected in spring 2026, with Talen acting as retail electricity supplier to Amazon and PPL Electric Utilities handling delivery. The release does not explain why the structure changed, so it is described here only as the company stated it. Law firm summaries of the federal energy regulator's work (below) show this is an area regulators are still reshaping.

Clinton, Illinois. Meta's January 2026 announcement lists the 2025 Constellation agreement as extending the life of the Clinton plant by 20 years. Meta's post gives no capacity figure for Clinton, so none is given here.

Ohio and Pennsylvania. In the same announcement Meta says it will buy more than 2.1 GW from the Perry and Davis-Besse plants in Ohio under additional 20 year agreements with Vistra, and that uprates at those plants and Beaver Valley in Pennsylvania total 433 MW, expected online in the early 2030s. Meta describes these as the largest nuclear uprates backed by a corporate customer in the United States, which is its own claim.

Restarts: three plants, three schedules

Restarts are attractive because the site, the grid connection and the workforce already exist. They are also hard, because a plant that has stopped has to be inspected, repaired and relicensed.

Crane Clean Energy Center, Pennsylvania. This is the former Three Mile Island Unit 1, which Constellation retired in 2019. Constellation's 20 September 2024 release says it signed a 20 year PPA with Microsoft, that the restored output is about 835 MW (the plant's pre-retirement capacity was 837 MW), and that the unit was expected online in 2028. Constellation does not give a restart cost in that release, and says restart needs NRC approval and state and local permits. The NRC is the US Nuclear Regulatory Commission.

The date has moved earlier on paper. Latitude Media in September 2025 reported the target moved up to 2027. ANS reporting up to 30 July 2026 says restart is possible as early as 2027, notes that Constellation applied on 27 February 2026 for three licence amendments, that the NRC issued a preliminary environmental assessment with a finding of no significant impact on 9 June 2026, and that a public meeting on emergency preparedness was held on 30 July 2026. On 1 June 2026 the federal energy regulator, FERC, approved a request to move grid connection rights from Constellation's Eddystone plant to Crane.

The environmental step is now done. World Nuclear News reported on 28 September 2026 that the NRC, with the Department of Energy's Office of Energy Dominance Financing as a cooperating agency, issued the final environmental assessment and finding of no significant impact for restarting the unit. That is not the restart approval itself. Constellation still needs the NRC to grant one exemption and three licence amendments, which would let the unit run to 19 April 2034, the expiry date of its renewed licence. The company says it will also seek to extend operations to 2054. The same report says the Department of Energy closed a $1 billion loan to Constellation in 2025 to help finance the restart, which makes Crane, like Palisades and Duane Arnold, partly federally financed.

There is a disagreement about grid connection. ANS reports that a PJM analysis cited by Reuters suggested Crane might not be connected until 2031. Constellation's chief executive disputed that a delay of several years was likely. PJM has not published that analysis as a standalone document, so treat the grid date as open.

Palisades, Michigan. Palisades is an 800 MWe pressurised water reactor that ceased operation in May 2022. The US Department of Energy finalised a $1.52 billion loan guarantee in September 2024, and the NRC reinstated an operating status licence in August 2025 so the plant could receive fuel, according to Nuclear Engineering International on 10 July 2026. Holtec's earlier target of grid reconnection by the end of February 2026 was missed. Nuclear News reported on 8 July 2026 that more than 5,000 individual work activities remained, mostly routine maintenance, testing and inspection, and that the chief executive told the Financial Times he expected restart this year, ahead of a contract to supply power by March 2027.

Fuel loading then hit a setback. Michigan Public reported on 14 October 2026 that staff began loading fuel into the reactor in August and stopped after one fuel assembly tipped over. Holtec told the regulator the damage "prevents retrieval using the grapple on the refueling machine", so it asked for an emergency licence amendment allowing a new procedure to lift the assembly out and move it to a spent fuel pool in another building. The NRC approved the amendment, saying there is "reasonable assurance" that public health and safety will not be endangered, and it is still investigating why the assembly tipped. As of that report fuel loading remained paused, other restart work continued, and Holtec had given no new restart date. The practical reading: Palisades is the closest of the three restarts to operation, but its date now depends on how quickly the damaged assembly is removed and loading resumes.

Duane Arnold, Iowa. NextEra announced on 27 October 2025 a restart of the 621.9 MWe boiling water reactor. Google buys power under a 25 year agreement and Central Iowa Power Cooperative takes the remaining output, with the split not stated. NextEra said the restart was slightly delayed to early 2029 from an earlier possible late 2028. The reactor began commercial operation in February 1975, was licensed through 2034, and shut after August 2020 windstorm damage to its cooling towers. Exchange Monitor reported on 8 September 2026 that the Department of Energy's Office of Energy Dominance Financing issued a loan of about $1.9 billion for the restart, which it described as the largest yet for reviving a nuclear plant. A source in September 2025 gave the capacity as about 600 MW, which is a rounder number for the same unit.

So three restarts have three situations: Crane with its environmental review finished and licence amendments pending, Palisades paused partway through fuel loading with no confirmed grid date, and Duane Arnold more than two years away.

New reactors: contracts now, power later

For new designs the deals fund development, not electricity this year.

Meta's 9 January 2026 post says that with TerraPower it has agreements covering two new Natrium units, up to 690 MW of firm power with delivery as early as 2032, and rights to energy from up to six more units, 2.1 GW, targeted for 2035. That adds to eight potential units, 2.8 GW of baseload and 1.2 GW of built-in storage. With Oklo, Meta describes a campus in Pike County, Ohio that could start as early as 2030 and supply up to 1.2 GW into the PJM market. Meta's post states no contract length for either, and describes the work as multi-year. Holtec separately plans two SMR-300 units, about 600 MWe, with grid synchronisation targeted for 2030 per NEI in July 2026.

Treat every date in this section as a developer target. First-of-a-kind reactors are exposed to licensing, construction and supply chain risk, and none of these had delivered power to customers as of 19 October 2026 according to the cited company statements.

Why nuclear, and what it does not solve

The attraction is steady output day and night. Data centres run all day, and nuclear plants run at high output almost all the time. Nuclear also produces no carbon dioxide while operating, which matters because several buyers have public climate goals.

The limits are timing and scale. The PJM capacity auction release of 17 December 2025 shows nuclear providing 21 percent of cleared capacity in the 2027/2028 auction, behind natural gas at 43 percent. In the next auction, for 2028/2029, PJM's release of 14 July 2026 puts nuclear at 20 percent and natural gas at 46 percent. That is the existing fleet, not additions. The same July release says the auction cleared only 525 MW of new generation and generation uprates across the whole PJM region, and that total cleared capacity was 6,831 MW short of PJM's reliability requirement. Against that gap, the three restarts add roughly 835 MW, 800 MW and 622 MW, about 2.3 GW in total, and none was producing as of 19 October 2026. Compare that with forecast data centre demand measured in tens or hundreds of gigawatts, discussed in the companion demand forecasts post. Nuclear helps with part of the need, and gas, renewables and storage cover the rest, as described in the gas turbines post.

What is firm and what is uncertain

Firm:

• The Crane, Susquehanna and Duane Arnold agreements exist and are described by the companies and by trade reporting.
• Palisades missed its February 2026 grid target, and fuel loading was paused after a fuel assembly tipped (Michigan Public, 14 October 2026).
• The NRC finished its environmental review of the Crane restart (World Nuclear News, 28 September 2026).
• Duane Arnold slipped to early 2029 by NextEra's own statement.

Uncertain:

• Palisades' grid date, which depends on removing the tipped fuel assembly and resuming fuel loading.
• Crane's real grid connection date (2027 target against a reported 2031 analysis).
• Whether any new reactor design delivers on the 2030 to 2035 targets.
• Prices. Almost none of these contracts publish a price. Do not assume a price from the announced capacity or the loan size.

What to watch next

• NRC decisions on Crane's exemption and three licence amendments, and Holtec's removal of the damaged assembly and restart of fuel loading at Palisades.
• Whether PJM's connection analysis for Crane is resolved.
• Meta's announced project milestones at Oklo and TerraPower sites, such as construction starts.
• The federal energy regulator's work on connecting large loads. Law firm summaries describe orders issued on 18 June 2026 to the six regional grid operators; no final rule had been issued as of 19 October 2026.
• PJM's 2029/2030 capacity auction, which its July 2026 release says is scheduled for December 2026.

For the money behind AI infrastructure, see Anthropic's compute commitments and OpenAI's Stargate and gigawatts.

If your own team tracks supplier dependencies, Safeguard offers SBOM and dependency scanning and a free scan at https://gold.safeguard.sh/scan.

Quick check

Sources

• Meta announces nuclear energy projects, up to 6.6 GW (Meta, 9 January 2026, updated 12 January 2026)
• Constellation to launch Crane Clean Energy Center (Constellation, 20 September 2024)
• Talen Energy and Amazon agreement (Talen Energy, SEC filing, 11 June 2025)
• Palisades: restart projects, Holtec IPO, lawsuit dismissal, but no restart date (Nuclear News, 8 July 2026)
• Palisades restart enters final phase (Nuclear Engineering International, 10 July 2026)
• NextEra and Google ink a deal to restart Duane Arnold (Nuclear News, 28 October 2025)
• DOE issues $1.9 billion loan for NextEra's Duane Arnold restart (Exchange Monitor, 8 September 2026)
• Crane restart news tag page (American Nuclear Society, accessed 19 October 2026)
• NRC completes environmental review of Crane restart (World Nuclear News, 28 September 2026)
• Regulators approve plan to remove damaged fuel assembly at Palisades (Michigan Public, 14 October 2026)
• PJM capacity auction procures 138,318 MW of generation resources (PJM, 14 July 2026)
• Restarts and uprates are powering the nuclear renaissance (Latitude Media, 4 September 2025)
• PJM auction procures 134,479 MW of generation resources (PJM, 17 December 2025)
• Large load show cause orders, law firm summaries index (JD Supra, June 2026)

Last reviewed: 19 October 2026.