star power

A US lab's nuclear fusion breakthrough could transform clean energy

An experiment at Lawrence Livermore National Laboratory could lead to a source of carbon-free energy

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A lab in the UK experiments with nuclear fusion.
A lab in the UK experiments with nuclear fusion.
Photo: Leon Neal (Getty Images)

A lab in the US may have had a breakthrough in nuclear fusion, the potentially limitless alternative energy which produces no carbon emissions.

Unlike nuclear fission, which is the reaction used by existing nuclear power plants, fusion does not produce radioactive waste, nor can it be used for weapons, according to the International Atomic Energy Agency. Nuclear fusion uses hydrogen and lithium, elements that exist in abundance.

The news was first reported by the Financial Times, based on sources with knowledge of the experiment at the US government-funded Lawrence Livermore National Laboratory in California. The lab is currently analyzing the data and is yet to confirm results, but it’s expected to make an announcement on Tuesday, Dec. 13. According to the FT, the experiment produced more energy than expected, damaging some of the lab’s equipment.


The convergence of the climate and fuel crises is making the prospect of nuclear fusion-generated energy all the more urgent

The experiment, conducted within the last two weeks, has generated about 2.5 megajoules of energy, 120% more than the 2.1 megajoules put into creating it. The excess energy generated isn’t much, underscoring that it could take decades more before nuclear fusion begins to fuel power plants.


However, the shift from net-negative energy generation to net-positive is a result that has eluded scientists for decades and represents a potential turning point in developing this form of alternative energy.

Nuclear fusion is the same reaction that powers the sun

The Lawrence Livermore Lab uses a process called inertial confinement fusion, which involves powerful lasers pointed at a 2mm-wide plastic capsule filled with hydrogen. When the capsule implodes, it produces a massive burst of energy similar to that found in the center of stars.


Governments, and increasingly, private companies, have poured billions into nuclear fusion. The effort has a long history going back to the 1950s, but the promise has remained out of reach of existing technology. If confirmed, the breakthrough at the Lawrence Livermore Lab could bring this dream of limitless and safe alternative energy closer to reality.