All Access

Climate Deals

Standard

Climate Deals Thought Bubble

Thought Bubble

Climate Deals Alerts

Alert

mustard

BFD Expert Voices - Climate Deals

BFD Expert Voices

Venture-backed fusion startup Xcimer Energy has started operating the world's largest privately owned laser in a 74,000-square-foot facility in Denver. 

Why it matters: It's part of a plan to commercialize low-cost fusion using gas lasers. 

Zoom in: The "kilojoule-scale" laser is called Phoenix and it's a proof of concept for an even bigger laser called Vulcan, which the company plans to build.

Xcimer spent the bulk of its $100 million Series A on developing Phoenix, and a Series B is expected soon. 

"Phoenix is the proof point that we can actually do this in an engineering sense," and from a supply chain perspective, says Xcimer co-founder and President Alexander Valys.

Catch up quick: Axios Pro was the first to fire a laser that's a component of Phoenix last year. 

How it works: Xcimer uses a form of ultraviolet gas laser called an excimer laser, which can produce longer pulses, delivering lower-power, less-expensive systems.

Xcimer ultimately plans to use its lasers to compress nuclear fuel and kick off a fusion reaction.  

Laser-based fusion, called inertial fusion, was first demonstrated at the lab scale back in the 1980s by the U.S. government using X-rays from underground nuclear tests. 

In 2022, the National Ignition Facility achieved fusion ignition and breakeven using an inertial fusion design. NIF's laser system is expensive and complex, and the startup says its xcimer lasers can enable to fusion to be more low cost and able to be commercialized. 

Follow the money: Company investors include Hedosophia, Breakthrough Energy Ventures, Lowercarbon Capital, Prelude Ventures, Emerson Collective, Gigascale Capital and Starlight Ventures.

The DOE has also awarded the company $9 million.

Following electricity demand growth, investors have been backing private fusion companies, and some fusion firms have even turned to public markets. 

What's next: Xcimer plans to build its next laser, which is planned to be the world's largest either privately owned or public, in the early 2030's. 

Xcimer starts up world's largest privately owned laser

Backed by VCs and the DOE, there's now a giant laser operating in Denver.

Industrial workshop with a large yellow overhead crane labeled XCIMER across the ceiling. Busy floor with blue-framed equipment, pipes, workstations, and a few workers; American flag on the wall.

Xcimer Energy's laser called Phoenix in a facility in Denver. Photo courtesy of Xcimer Energy

Venture-backed fusion startup Xcimer Energy has started operating the world&#x27;s largest privately owned laser in a 74,000-square-foot facility in Denver. Why it matters: It&#x27;s part of a plan to commercialize low-cost fusion using gas lasers.

topics

politics-policy

epstein-files

donald-trump

2026-midterm-elections

immigration

behind-the-curtain

race-and-equity

technology

privacy-tech-regulation

automation-and-ai

tiktok-news

big-tech

social-media

cybersecurity

economy

social-security

inflation

tariffs

federal-reserve

transportation

business

c-suite

retail-news

media

elon-musk

dealmaking

health

rfk-jr

drug-prices

axios-explains-abortion

public-health

world

israel

axios-explains-ukraine

iran

russia

china

energy-climate

nuclear-energy

climate-energy-policy

climate-change

extreme-weather

alternative-energy

electric-vehicles

science

emerging-tech

biomedicine

newsletters

charlotte

salt-lake-city

denver

fort-lauderdale

boulder

kansas-city

austin

chicago

dallas

detroit

washington-dc

atlanta

indianapolis

nashville

nw-arkansas

columbus

hollywood

richmond

san-francisco

boston

des-moines

houston

phoenix

miami

philadelphia

seattle

new-orleans

colorado-springs

huntsville

raleigh

san-antonio

twin-cities

pittsburgh

arapahoe

douglas

san-diego

tampa-bay

portland

cleveland

axios-local

axios-pro

axios-live

the-axios-show

Xcimer starts up world's largest privately owned laser

What to read next