Valar Atomics, a U.S. small modular reactor startup, has raised $1 billion in a Series B led by Sequoia Capital to scale production of its helium-cooled, TRISO-fueled high-temperature gas reactors. The company says its Ward 250 reactor achieved criticality in June and powered an NVIDIA Blackwell system, a first for advanced reactors directly fueling AI infrastructure. The funding will support a vertically integrated model that includes in-house fuel production, aiming to cut build times from years to months. Nuclear power is a key carbon-free baseload source, and SMRs are attracting heavy investment as AI data centers drive surging electricity demand. Valar's approach treats reactors like factory hardware, with each unit feeding data into the next to compress construction timelines. The company also secured a $200 million credit facility. While the valuation was not disclosed, Bloomberg reports it at $6 billion, triple the previous mark. This round signals growing confidence in SMRs as a practical decarbonization tool for the grid.
