Sam Atlman-backed Exowatt wants to power AI data centers with billions of hot rocks

Summary

When Hannan Happi started thinking about how to solve the AI power crisis, he kept one figure in mind: one cent per kilowatt-hour. “We went through all sorts of configurations and designs,” Happi, co-founder and CEO of Exowatt, told TechCrunch. “They all look different from each other. We tried to learn from everyone one of them: How do I reduce structural costs? How do I reduce maintenance costs? How do I optimize for this?” After years of brainstorming and building, Exowatt’s first step toward that goal is a simple box the size of a shipping container topped with a clear awning. Inside is similarly simple. If Exowatt can deliver on its promise of delivering cheap solar power that generates electricity 24-7, it could upend the data center market and broader energy world, delivering round-the-clock power at very low cost. To scale production in pursuit of the one-cent per kWh target, Exowatt has raised an additional $50 million in an extension to its $70 million Series A round that closed in April, TechCrunch has exclusively learned. The extension was led by MVP Ventures and 8090 Industries with participation from Atomic, BAM, Bay Bridge Ventures, DeepWork Capital, Dragon Global, the Florida Opportunity Fund, Massive VC, New Atlas Capital, Overmatch, Protagonist, and StepStone. Previous investors include Andreessen Horowitz and Sam Altman. Happi said that Exowatt wasn’t looking to raise additional capital after the April round, but “strong momentum we saw in the market” and “strong investor interest” encouraged him to take the new money at a higher valuation. Exowatt’s backlog is currently about 10 million P3 units representing 90 gigawatt-hours of capacity, he said. “The goal is to scale as fast as possible to the millions and ultimately billions of units,” he said. The company should hit its one-cent target when production hits around 1 million units per year, Happi said. Techcrunch event San Francisco | October 13-15, 2026 Exowatt is basically repackaging a techn...