Focused Energy has raised $240M to turn a single landmark experiment into a power plant. The German laser-fusion company plans to put its first demonstration system, called Lighthouse, on the grounds of a decommissioned nuclear fission plant that RWE operated in Germany. RWE is also the lead investor in the round.
SPRIND, the German Federal Agency for Breakthrough Innovation, Prime Movers Lab and the European Innovation Council Fund took part as well. The choice of site is a practical one: the old plant already has grid connections, cooling infrastructure and regulatory frameworks written for nuclear facilities.
From the NIF shot to a reactor
The company works on inertial confinement fusion. Lasers squeeze a fuel target until conditions get extreme enough for atoms to fuse and release energy. In December 2022, the National Ignition Facility at Lawrence Livermore National Laboratory in California did exactly that. It remains the first and only controlled fusion reaction to give off more energy than it took to ignite.
Debbie Callahan helped design the fuel target for that experiment. She joined Focused Energy in December as chief strategy officer, and her job is to make the target simple enough to manufacture in volume. The NIF target is complex and hard to build, and the facility fires about 400 shots per year. A commercial reactor would need 10 shots per second, roughly 864,000 per day.
One big change is dropping the hohlraum, the precision-made gold cylinder the NIF uses to turn laser light into X-rays that then compress the fuel pellet. Focused Energy uses “direct drive,” where the lasers hit the pellet themselves. That should raise efficiency and make targets easier to produce, both needed for a plant that runs around the clock.
A long way from the lab
The gap is wide. The NIF’s net gain was measured against the energy that reached the fuel, not the total drawn by the laser system, which is orders of magnitude larger. A power plant has to come out ahead on total input. That calls for more efficient lasers and higher-yield targets, and the company still has to show its system can deliver the precision, repetition rate and efficiency for continuous operation.
Rivals are moving fast. Inertia Enterprises, which is building its own inertial confinement reactor, closed a $450 million Series A in February. Last week Thea Energy brought in $100 million. Bill Gates backs Type One Energy, which has collected nearly $90 million of a targeted $250 million Series B. Commonwealth Fusion Systems took in $863 million for its magnetic confinement design.
The report on the round points to RWE as the most telling signal in it: a large European utility with long experience running power plants is putting in money and offering a site. Whether Lighthouse can carry fusion from laboratory physics to grid power is, in the report’s words, “the $500 million question.”
