Nuclear startup X-energy has raised $700 million in a Series D round, the company told TechCrunch.
The new fundraiser comes less than a year after it raised its Series C from $500 million to $700 million, bringing its total raised in the last year to $1.4 billion, a sizable sum even in the tumultuous world of nuclear startups. X-energy has raised $1.8 billion to date.
Energy X said the new injection will help build the supply chain for its small modular reactors (SMRs). So far, the startup says it has orders for 144 SMRs capable of generating 11 gigawatts of electricity. Customers include Amazon, Dow and UK energy company Centrica.
The new round was led by Jane Street, which joined as an investor in the expanded Series C. Other participating investors include funds Ares Management, ARK Invest, Corner Capital, Emerson Collective, Galvanize, Hood River Capital Management, NGP, Point72, Reaves Asset Management, Segra Capital Management and XTXture.
X-energy develops high-temperature, air-cooled reactors, a type most recently used in Japan and China. Each of the Xe-100 reactors can produce 80 megawatts of electricity and is powered by billiard ball-sized pebbles coated with carbon containing uranium particles. Inside the reactor, helium gas flows over the pebbles, collecting heat, which is transferred to a steam turbine to generate electricity.
Like other nuclear startups, X-energy has sparked a wave of interest from tech companies and data center developers.
Amazon’s Climate Pledge Fund led the startup’s first Series C tranche. The tech company also announced last year that it would buy more than 600 megawatts of nuclear power in the Pacific Northwest and Virginia, with the reactors coming online in the early 2030s. In total, Amazon’s deal with X-energy could deploy up to 5 gigawatts by 2039.
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X-energy is in a race with several other SMR startups to revitalize the nuclear industry in the United States. While many of the designs look promising, only a handful SMR power plants have been built to date, none of which are located in the United States.
