US’ laser-powered nuclear fusion achieves new net-positive energy records: Report

The National Ignition Facility (NIF) has reportedly pushed the boundaries of fusion energy and achieved significant increases in power output in its latest experiments. 

Sources close to the project have revealed to TechCrunch that recent attempts have seen the net-positive fusion experiment yield a first 5.2 megajoules and subsequently a remarkable 8.6 megajoules of energy.

According to a report recently published by Lawrence Livermore National Laboratory (LLNL), the NIF had achieved ignition for the seventh time in February 2025, and the latest achievement seems to have emerged from the eighth time. However, there is no official communique on this matter.

“On Feb. 23, 2025, NIF achieved ignition for the seventh time while setting a new target gain record (energy yield vs. energy on target) of 2.44. The 2.05 MJ shot yielded 5.0 MJ, highest for a 2.05 MJ shot and the second highest overall,” LLNL had noted earlier.

Progress over previous milestone

This surge in energy production marks a pivotal development, substantially building upon the NIF’s landmark 2022 success.

It was then that scientists first achieved a controlled fusion reaction that demonstrably released more energy (3.15 megajoules) than the 2.05 megajoules of laser energy directly applied to the fuel target. This was the first controlled fusion experiment to do so.

Despite the reported increases in yield, the energy produced is not sufficient for grid-scale power generation, nor does it offset the total energy consumed by the NIF to conduct the experiments. 

Inertial confinement is one of the primary methods being researched globally to achieve controlled fusion. The other main approach, magnetic confinement, uses strong magnetic fields to contain and compress plasma to induce fusion.

“For the last six decades, LLNL researchers and their colleagues have been working to achieve one of the most challenging goals in all of science and a primary objective of NIF: fusion ignition,” remarked the Lab.

The facility was not designed for continuous power output; for example, the 2022 net-positive shot required approximately 300 megajoules to operate the laser system alone. The experiments serve as continued demonstrations of controlled nuclear fusion principles.

Using inertial confinement fusion

The NIF employs a method known as inertial confinement fusion. This process involves a tiny pellet of fusion fuel, typically isotopes of hydrogen called deuterium and tritium, coated in diamond and encased within a small gold cylinder called a hohlraum. 

This target assembly is then placed in a 10-meter-diameter spherical vacuum chamber. In a precisely orchestrated event, 192 high-powered laser beams converge on the hohlraum.

These X-rays then irradiate the fuel pellet, causing its outer diamond layer to rapidly expand. This expansion creates an inward compressive force on the deuterium-tritium fuel, leading to conditions under which their nuclei fuse and release energy.

The reported advancements at NIF contribute to the ongoing scientific investigation into the feasibility of nuclear fusion as a potential future energy source.

“Additional experiments using higher laser energies and producing even higher energy yields are expected in the coming months, further demonstrating that NIF can repeatedly conduct fusion experiments at multi-megajoule levels of energy output,” LLNL had highlighted in a previous press release.