Xcimer is betting that the key to fusion energy is not better tokamaks or stellarators — it is lasers. Specifically krypton fluoride excimer lasers, which are cheaper, more efficient, and commercially available compared to the bespoke optics that made the National Ignition Facility cost $3.5 billion to build. NIF proved ignition works. Xcimer's whole thesis is making it affordable. They raised $100 million in 2024 before they had a working machine. Breakthrough Energy Ventures wrote that check. That is a very large bet on a very early idea — and it might be exactly the right one.
Founded
2022
HQ
Denver, Colorado
Total Raised
$100 Million
Founder
Conner Galloway
Status
Private
Website
www.xcimer.netTHE ORIGIN STORY
Conner Galloway founded Xcimer in 2022 after studying the economics of laser-driven inertial confinement fusion. The National Ignition Facility at Lawrence Livermore had achieved ignition in December 2022 — proving that fusion could produce more energy than the lasers put in.
But NIF's approach used extraordinarily expensive custom solid-state lasers. Galloway's insight was that krypton fluoride (KrF) excimer lasers offer much higher efficiency and far lower cost per joule of energy delivered to a target.
The excimer laser approach had been studied for decades but never commercially developed for fusion. Xcimer was built to change that.
WHAT THEY ACTUALLY DO
Pre-revenue. Xcimer is in deep technology development.
The long-term commercial model is selling electricity from fusion power plants to utilities and grid operators. Between now and that point, revenue will come from government grants and DOE fusion program contracts.
THE PRODUCTS
Fusion power plant (development stage). The primary technical asset is Xcimer's high-energy krypton fluoride excimer laser driver system, designed to deliver ignition-level energy at a fraction of NIF's per-shot cost.
No commercial product has shipped.
HOW THEY GREW
Raise venture capital to fund a demonstration-scale plant. Partner with national laboratories for target physics and laser performance validation.
Build a defensible IP portfolio around the KrF excimer laser approach to inertial confinement fusion. Land government contracts to supplement private capital.
Prove the energy gain ratio required for commercial viability at a fraction of the cost of NIF.
THE HARD PART
Fusion has been 20 years away since 1950. Xcimer has to prove not just that ignition is repeatable — NIF showed that — but that the KrF laser approach can achieve the energy gain ratios needed for commercial power generation, that the system can be cycled at the frequency required for a power plant, and that the economics actually work at scale.
Every step is hard. The first step is just getting the laser system to perform.
MONEY TRAIL
Series A
2024 · Led by Breakthrough Energy Ventures
$100M raised
WHO BACKED THEM
Breakthrough Energy Ventures (led $100M Series A). Other participants include investors aligned with the deep decarbonization mission.
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