A UK company developing a novel inertial fusion approach that uses hyper-velocity projectile impacts to compress fuel targets. First Light achieved independently verified fusion neutrons in 2022.
First Light Fusion was founded in 2011 as a spinout from the University of Oxford by Yiannis Ventikos, a professor of engineering science, and Nicholas Sherlock (now Nicholas Hawley), a doctoral researcher. The company is based in Yarnton, Oxfordshire, near the university campus.1
The founding concept drew on Ventikos's research into the extreme pressures and temperatures generated during cavity collapse in fluids — a phenomenon known as inertial confinement driven by shock convergence rather than by lasers.
First Light pursues a form of inertial confinement fusion (ICF) that replaces the massive laser arrays used at facilities like the National Ignition Facility with a conceptually simpler driver: a hyper-velocity projectile. A projectile is accelerated to speeds of several kilometers per second and impacts a carefully engineered fuel target. The target's internal geometry is designed to amplify and focus the resulting shock wave, compressing a small quantity of deuterium-tritium fuel to fusion conditions.2
In a power plant concept, projectiles would be launched electromagnetically at a rate of roughly one per minute, with each shot producing a burst of fusion energy captured by a liquid lithium blanket surrounding the reaction chamber.
In April 2022, First Light announced that it had achieved fusion neutron production using its projectile-driven approach. Critically, this result was independently verified by the UK Atomic Energy Authority (UKAEA), which confirmed the detection of neutrons consistent with deuterium-deuterium fusion reactions.3
First Light has raised over $100 million in funding from investors including IP Group, Oxford Sciences Innovation, and various venture capital firms. The UK government has also provided support through the UK Atomic Energy Authority's fusion program.4
The company is developing its next experimental platform, Machine 4, a larger electromagnetic launcher designed to achieve higher projectile velocities. In parallel, the target design team is working on "amplifier" targets that more efficiently convert projectile kinetic energy into fuel compression.
First Light's proposed reactor design has several attractive features. The driver (electromagnetic launcher) is physically separated from the reaction chamber, meaning it is not exposed to neutron damage. The targets are mass-manufactured consumables, potentially leveraging precision manufacturing techniques from other industries. The liquid metal blanket provides both neutron shielding and tritium breeding.5
First Light represents one of the most unconventional approaches in the fusion landscape. By decoupling the driver from the target physics, the company avoids some of the most expensive and complex engineering challenges faced by laser-driven ICF. The 2022 neutron verification was a meaningful proof-of-concept, but the path from initial neutron detection to energy-producing fusion remains long and technically demanding.