Nuclear fusion has long been hailed as the “holy grail” of clean energy — a power source that could one day deliver limitless electricity without the harmful emissions of fossil fuels or the long-lived waste of nuclear fission. While achieving controlled fusion has proven one of science’s most formidable challenges, recent developments suggest that researchers are making tangible progress. A major player in this endeavor, the U.S. National Ignition Facility, has reported a series of significant milestones in laser-powered fusion.
Gradual Power Increase at NIF
The world’s only net-positive fusion experiment, conducted at the U.S. Department of Energy’s National Ignition Facility (NIF), has been steadily increasing its energy output, according to TechCrunch. Recent attempts reportedly achieved energy yields of 5.2 megajoules and then 8.6 megajoules, according to a source familiar with the project.
Improvement Over the 2022 Breakthrough
These new results represent substantial progress compared to the historic 2022 experiment, which was the first to produce more energy from a controlled fusion reaction than the amount consumed. That earlier shot generated 3.15 megajoules of energy from 2.05 megajoules delivered by the lasers to a fuel pellet the size of a BB.
Still Far From Grid-Level Energy
Despite the gains, none of the experiments have yet generated enough power to return electricity to the grid or even to offset the total energy used by the facility itself — which was never designed with that purpose in mind. For example, the original net-positive experiment required 300 megajoules just to operate the laser system. Nevertheless, the outcomes continue to validate that controlled nuclear fusion is not merely theoretical.
Inertial Confinement Fusion at Work
NIF’s approach relies оn inertial confinement fusion. In this method, the fusion fuel іs encased іn diamond and placed inside a small gold cylinder called a hohlraum. This tiny pellet іs inserted into a 10-meter-wide spherical vacuum chamber, where іt іs targeted by 192 high-powered laser beams.
The lasers vaporize the cylinder, producing X-rays that strike the fuel pellet. The diamond layer оf the pellet absorbs sо much energy that іt transforms into an expanding plasma, compressing the deuterium-tritium fuel inside. This compression causes the atomic nuclei tо fuse, releasing a burst оf energy.
Magnetic Confinement and Other Efforts
An alternative fusion approach, magnetic confinement, uses superconducting magnets to contain plasma under the extreme conditions necessary for fusion. While no magnetic confinement experiments have yet produced net-positive energy, several projects are underway with the goal of reaching that threshold.
Additionally, several startups are working on inertial confinement methods. Notable among them are Xcimer Energy and Focused Energy.
