Analysis has confirmed that an experiment conducted in 2021 created a fusion reaction energetic enough to be self-sustaining, which brings fusion one step closer to being useful as a source of energy.
The fusion ignition took place on 8 August 2021 at the Lawrence Livermore National Laboratory’s National Ignition Facility (NIF) in California, but NIF researchers have not been able to reproduce this landmark achievement since. They have spent the past year analysing the experimental conditions that led to their success 12 months ago.
Fusion ignition occurs when the energy being given off by the fusion reactions heats the fuel mass more rapidly than various loss mechanisms cool it. At this point, the external energy needed to heat the fuel to fusion temperatures is no longer needed.
NIF announced the peer-reviewed results of its findings last August, where a yield of more than 1.3 megajoules (MJ) was reportedly achieved by the team of scientists in a groundbreaking physics achievement.
“This advancement puts researchers at the threshold of fusion ignition, an important goal of the NIF, and opens access to a new experimental regime,” NIF said.
The experiment was enabled by focusing laser light from NIF – the size of three football fields – onto a target a few millimetres wide that produces a hot-spot the width of a human hair, generating more than 10 quadrillion watts of fusion power for 100 trillionths of a second.
Research Team Aims To Fine-Tune Setup
Armed with data from last year’s experiment, the research team believes they will be able to fine-tune their experimental setup to allow ignition to be achieved reliably in the future.
Adjustments the research team hopes to institute include improvements to the system that facilitates energy delivery to the central heat area, or “hotspot”, as well as increasing pressure in this location in order to optimise the regulation of fuel used in the nuclear fusion process.
Scientists have been successfully running fusion experiments since the 1950s, but they have been unable to generate more energy from a fusion reaction than the systems consume.
The world’s largest nuclear fusion project, the €20bn ($20.3bn) International Thermonuclear Experimental Reactor (Iter), is under construction in France. It is intended to demonstrate fusion power can be generated on a commercial scale.