Big Tech bets on nuclear uprates as the easy wins start running out

Big Tech has found a faster way to get more nuclear power onto the grid. The catch is that there aren’t many places left to do it.

Google, Amazon, Microsoft and Meta need enormous amounts of electricity for AI data centers and cloud computing. A growing share of that hunger is now being fed by upgrading reactors that already exist, rather than waiting years for new ones to be built.

The details: more megawatts from the same old plants

The industry term is an uprate. Think of it as tuning a car’s engine for more horsepower instead of buying a new car. Operators modernize equipment at an existing reactor so it can produce more electricity than it was originally rated for.

The largest example so far is a deal between Google and Constellation Energy announced on October 6, 2026. It is a 20-year power purchase agreement, or PPA, which is a long-term contract in which a buyer commits to purchasing a plant’s electricity at agreed terms.

Under the deal, uprates across 11 reactors are expected to add 890 MW of capacity. All of those reactors sit on the PJM grid, one of the largest regional power networks in the US.

The investment involved exceeds $4.3 billion. Initial capacity is expected to come online by 2028, with the full project targeted for completion in the early 2030s.

Amazon is pursuing the same playbook. Its own recent agreement with Constellation supports an uprate of about 190 MW at the Calvert Cliffs plant in Maryland, part of the company’s broader strategy of buying nuclear output.

Microsoft has taken a different route. It plans to bring the former Three Mile Island Unit 1 back into service, a restart rather than an upgrade.

Google’s nuclear footprint now stretches well beyond the Constellation deal. The total nuclear capacity the company has enabled exceeds 1.5 GW, counting both uprates and restarts. That sits alongside a separate 15-year supply agreement covering 2,700 MW.

Zoom out to the whole sector, and the numbers get larger. Tech company PPAs with US reactors now cover approximately 8.5 GW. Deals tied to small modular reactors, or SMRs, reach 45 GW.

SMRs are compact reactor designs meant to be built more quickly and in more locations than traditional plants. The gap between those two figures is telling: most of the SMR capacity is a promise about the future, while the existing-reactor deals involve plants that are already running.

Background: nuclear’s unlikely second act

The arrival of AI changed the math. Data centers need power that runs around the clock, regardless of weather. Electricity demand from these facilities is projected to double by 2030, and that puts reliable baseload generation like nuclear back in the spotlight.

What this means: a short-term fix with a ceiling

Uprates solve a timing problem. Tech companies need power in the near term, and new reactors can’t arrive fast enough to meet it. But this is a finite resource. Each reactor can only be pushed so far, and the number of plants suitable for meaningful uprates is limited.

Nuclear operator stocks have seen sharp increases as tech demand has grown. Operators such as Constellation and Vistra are positioned to potentially benefit from continued appetite for nuclear capacity.

These projects could create thousands of jobs in construction and plant operations. More output from existing reactors could also improve grid reliability, with tech companies footing much of the bill.