Xcimer

Xcimer Energy is an inertial fusion energy company that combines novel excimer-based laser technology with proven science to accelerate the commercial deployment of fusion power. Founded in 2022 and headquartered in Denver, Colorado, the company is developing the world's highest-energy laser system — designed to produce up to 10 times higher laser energy at 10 times higher efficiency and over 30 times lower cost per joule than the National Ignition Facility laser. The company was selected for a $9 million award from the U.S. Department of Energy's Milestone-Based Fusion Development Program. In June 2024, Xcimer raised a $100 million Series A round led by Hedosophia, with participation from Breakthrough Energy Ventures, Lowercarbon Capital, Prelude Ventures, and Emerson Collective. In June 2026, the company activated Phoenix, the world's largest privately owned laser.