American scientists have for the first time managed to reach — and then improve on — a longtime goal of nuclear research.
Twice in under a year, researchers at California’s Lawrence Livermore National Laboratory have managed to trigger a fusion reaction resulting in a net energy gain, or producing more power than was used to fuel the experiment.
Their accomplishment represents an unprecedented “ignition” of the zero-carbon energy source that physicists have been trying to tap into since World War II.
As a power source, nuclear fusion far surpasses its controversial counterpart, nuclear fission. The latter produces as a byproduct dangerous waste that lingers for thousands of years.
The US Department of Energy described the laboratory’s work as “a major scientific breakthrough decades in the making.”
The laboratory first reached ignition in December of 2022 and again — even more powerfully — this July by shooting ultra-powered lasers into a centimeter-sized capsule “oven,” called a hohlraum.
The capsule contained variants of hydrogen gas called deuterium and tritium, which acted as fuel — like gasoline in a car — for the reaction.
The blasting lasers were converted into X-rays, which then transformed the deuterium and tritium from gas into plasma. Plasma is known as the fourth state of matter, coming after solids, liquids and gases in terms of molecular expansion.
The extremely high temperatures and pressure generated within the hohlraum caused the contents, also known as nuclei, to fuse by way of implosion.
Similar experiments have been conducted throughout history, particularly in the creation of the hydrogen bomb, but always with more energy being used than gained — until now.
The hydrogen bomb represented an advance on the work spearheaded by J. Robert Oppenheimer, the man who inspired Christopher Nolan’s “Oppenheimer.”
The film focuses on the titular character’s role in creating the twice-used atomic bomb during the 1940s.
The December achievement “surpassed the fusion threshold” by yielding 3.15 megajoules, up from the 2.05 megajoules which powered the test — about a 150% increase from start to finish. The July follow up produced even more, at 3.5 megajoules, the Financial Times reported, using preliminary data.
The Department of Energy stated this breakthrough “will pave the way for advancements in national defense and the future of clean power.”
Fusion produces more carbon-free energy and has a substantially less impactful aftermath compared to fission — which notably powered nuclear plants like Chernobyl, Three Mile Island and Fukushima.
The lab’s National Ignition Facility called the fusion ignitions an “exciting new scientific regime,” adding that “we plan on reporting those results at upcoming scientific conferences and in peer-reviewed publications.”
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