Google has signed a 20-year nuclear power purchase agreement valued at $4.3 billion to supply electricity for its data center expansion.

Google has struck a 20-year nuclear power purchase agreement (PPA) with Constellation Energy worth $4.3 billion, under which the tech giant will procure 2,700 megawatts (MW) over 15 years from Constellation's existing fleet to ensure grid stability and revenue certainty. The deal is part of a wider 3,590MW arrangement between the two companies.

The additional clean capacity will be enabled by upgrades to 11 existing nuclear plants across Illinois, Pennsylvania and New Jersey. Under the collaboration, Constellation will deploy Google Cloud's Gemini Enterprise agentic workflows across its operations to accelerate upgrade planning, streamline construction and optimise site output. The upgrades, which will improve the thermal and electrical efficiency of Constellation's sites, are projected to create around 7,200 new construction jobs and support roughly 4,400 existing jobs. The first upgrade is set to be delivered by 2028, with the final uprate expected to be complete by the end of 2032.

The new capacity is equivalent to installing several small modular reactors (SMRs) or one large conventional reactor, helping Google meet its expanding data centre energy needs. Google reported that its absolute emissions across all scopes rose by 18% last year as it expanded deployment of its AI technology. The tech giant experienced a surge in electricity demand, with its load growing by 37% year-on-year, which it said was "tempered by its AI-stack efficiencies," according to its annual report.

"We're committed to meeting our growth responsibly by actively investing in clean, reliable power that brings new capacity to our nation's grids," said Amanda Peterson Corio, Google's global head of energy and power. "Our agreement with Constellation to fund nuclear reactor uprates will strengthen the PJM grid, which serves 67 million people, all while protecting energy affordability and supporting local union jobs." PJM (Pennsylvania, Jersey and Maryland) Interconnection is the largest power grid operator, spanning 13 US states.

Constellation chairman, president and CEO Joe Dominguez said: "Preserving and expanding the output of the existing nuclear fleet and developing new clean generation is critical to meeting our nation's growing energy needs while keeping costs affordable for homes and businesses. This long-term clean energy collaboration with Google can serve as a model for how technology companies and the energy industry can work together to responsibly develop the digital economy and invest in our nation's energy infrastructure in a way that delivers grid-wide benefits for all, funded by private entities."

With this latest PPA, Google has now enabled over 1.5 gigawatts (GW) of new nuclear capacity for the US. Last week, Constellation signed another PPA worth $3 billion with Amazon. In September, Google unveiled its largest single investment in Europe, a €13 billion plan to support AI and digital infrastructure investments in Finland, powered by a variety of clean energy projects and a major nuclear supply deal.

The Trump Administration has targeted 400 GW of US nuclear capacity by 2050, up from 100 GW today. The Utility Power Reactor Incremental Scaling Effort (UPRISE) is central to that ambition, aiming to increase the power output of existing reactors, bring dormant facilities back online and complete stalled projects. Part of UPRISE's purpose is to "facilitate collaborative agreements between nuclear power plant owners and end users."