Fusion energy company Xcimer Energy said it has finalized an agreement for up to $30.5 million in additional federal funding through the U.S. Department of Energy’s (DOE’s) Milestone-Based Fusion Development Program.
The new DOE award, announced October 6, is for the program’s second budget period. It brings the total DOE funding for potential Milestone payments to Xcimer to $39.5 million as part of the federally supported fusion energy development program. Xcimer, headquartered in Denver, Colorado, in 2024 received a $4-million award from the government’s ARPA-E agency for a total of $43.5M in non-dilutive federal funding.
“America invented laser fusion, and America should lead its commercialization,” said Dario Gil, the DOE’s Under Secretary for Science. Gil, who leads the federal government’s Genesis Mission project, delivered a keynote address in late September at POWER’s Experience POWER event in Washington, D.C. “The Milestone-Based Fusion Development Program is built to turn American scientific leadership into commercial capability by putting private capital and private-sector execution behind ambitious, measurable goals. Xcimer is making real progress toward a new generation of laser fusion technology, and this award will help accelerate that work.”
Excimer Laser Architecture
Xcimer is developing an excimer laser architecture designed specifically for the requirements of a commercial fusion power plant. Unlike conventional approaches that rely on large numbers of solid-state laser beams and expensive optical components, Xcimer’s architecture uses cost-effective gas lasers, durable gas optics and a two-beamline configuration designed to deliver megajoule-scale laser energy repeatedly and economically, according to the company.
“We have moved from proving that the physics works to building the industrial technology that can turn fusion into a commercial energy source,” said Conner Galloway, co-founder and CEO of Xcimer Energy. “This additional milestone funding gives us another powerful mechanism to accelerate that work while keeping the majority of the investment and risk in the private sector. We are building the laser, manufacturing systems and supply chain required to make commercial laser fusion possible.”
Xcimer’s commercial fusion program is targeting electricity on the grid in the mid-2030s.
Phoenix Laser System
Xcimer in June of this year launched operations of Phoenix, the world’s largest privately owned laser system, which demonstrates key elements of Xcimer’s excimer-laser and gas-optics architecture. Phoenix is housed in Xcimer’s 74,000-square-foot Denver laser facility. POWER toured the lab on June 4. The company calls Phoenix “a proof of concept for an unconventional fusion architecture: a krypton fluoride [KrF] excimer laser using Stimulated Brillouin Scattering [SBS] to compress a microsecond-long pulse into the nanosecond timescales fusion requires. Phoenix is designed to demonstrate end-to-end integrated operation of excimer amplification and SBS pulse compression.”
The DOE this past summer approved the preconceptual design and technology roadmap milestones for Xcimer’s commercial power-plant architecture, Athena, also part of the DOE’s Milestone Program.
Xcimer and RTX in September announced a partnership to develop directed-energy air defense systems based on Xcimer’s pulsed laser technology. The companies plan to demonstrate the integration and containerization of Xcimer’s pulsed lasers with RTX’s air defense systems, offering the U.S. military new capabilities to defeat airborne threats. RTX also invested in Xcimer, directly strengthening Xcimer’s laser fusion energy roadmap.
Xcimer Energy is developing powerful lasers for commercial fusion energy and national security. The company has raised about $200 million from leading investors. including Breakthrough Energy Ventures, founded by Bill Gates; Lowercarbon Capital, Emerson Collective, Prelude Ventures, and others.
—Darrell Proctor is a senior editor for POWER.
