Ignition and net gain at Lawrence Livermore National Laboratory’s National Ignition Facility (NIF) in December 2022 focused global attention on the prospects of inertial fusion energy (IFE). First Light Fusion and the U.K. Atomic Energy Authority (UKAEA) acknowledged the achievement as they announced plans on January 25 to design and build a demonstration facility known as Machine 4 at UKAEA’s Culham Campus in Oxford, U.K., using First Light’s “projectile approach” to IFE. Construction is expected to begin in 2024, and operations are “likely to commence” in 2027.