Scientists from the National Ignition Facility (NIF) in California demonstrated "burning plasma" in the laboratory for the first time, a crucial step towards achieving practically limitless fusion energy, a report from the BBC explains.
Nuclear fusion occurs when two atoms slam together to form a heavier nucleus, releasing vast amounts of energy. For decades, scientists have been attempting to harness the process — the same one used by the Sun and stars to produce energy.
Now, according to a new study published in Nature, the scientific community has taken "a critical step towards self-sustaining fusion energy". The scientists at NIF, located at Lawrence Livermore National Laboratory (LLNL) in California, showcased a method for heating plasma to the incredibly high temperatures required, using the fusion reaction itself.
In an interview with VICE, study co-lead Alex Zylstra said "to get fusion we have to get the fuel very hot—something like 100 million degrees—and historically people have done that by heating the fuel. The significance of a burning plasma is that now the fusion itself is providing, actually, the majority of the heating of the fuel." This is key to making net fusion possible, as it would greatly reduce the energy input required to sustain the reaction in the first place.
192-laser experiment yields impressive results
To achieve the burning plasma milestone, the scientists trained 192 laser beams on a two-millimeter capsule containing thermonuclear fuel. The laser blast causes the fuel to heat and compress, which in turn makes the fuel, composed of deuterium and tritium, fuse into a helium atom. The scientists were able to extract a yield of 170 kilojoules from the peppercorn-sized capsule of thermonuclear fuel. While that isn't a massive amount of energy in and of itself, the researchers believe the experiment can be scaled for full-scale fusion experiments.
So far, scientists worldwide have only been able to produce less energy than the energy required to power their fusion reactors, or tokamaks. However, a series of breakthroughs in recent years suggests that we may be on the verge of net fusion energy production, an achievement that could provide the world with limitless sustainable energy. In September last year, for example, a Bill Gates-backed startup called Commonwealth Fusion Systems announced that it had developed a 20-tesla superconducting magnet that could help to maintain the fusion process for long periods. Another company, Tokamak Energy, announced only last month that its own magnet experiments were a success. It's taken decades to get to this point, but the world is racing towards net fusion energy, one breakthrough at a time.