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Huge lasers make conditions at the cusp of ignition for nuclear fusion

The immense lasers at the US National Ignition Facility have created the highest-pressure conditions ever made in a laboratory, bringing us a step closer to clean nuclear power
This artist?s rendering shows a NIF target pellet inside a hohlraum capsule with laser beams entering through openings on either end. The beams compress and heat the target to the necessary conditions for nuclear fusion to occur. Ignition experiments on NIF are the result of more than 50 years of inertial confinement fusion research and development, opening the door to exploration of previously inaccessible physical regimes
Illustration of a capsule being compressed by lasers at the US National Ignition Facility
NIF

A colossal laser system has created some of the most extreme conditions on Earth, bringing us one step closer to useful nuclear fusion power that would produce no hazardous waste. Researchers at Lawrence Livermore National Laboratory’s National Ignition Facility (NIF) in California have been attempting to jump-start nuclear fusion in the laboratory for decades, and now they are closer than ever.

NIF works by focusing 192 of the world’s highest-energy lasers into a single powerful beam that shines on a small plastic sphere full of hydrogen. The intense heat makes the plastic explode, compressing the hydrogen inside. If the pressure is high enough, the hydrogen atoms will begin to fuse together, releasing a huge amount of energy.

On 8 August, NIF achieved its highest energy yield yet, putting out more than 1.3 megajoules of energy. That is 10 quadrillion watts of fusion power for 100 trillionths of a second. “That, in reality, is what it takes to boil a kettle,” at Imperial College London told the èƵ Weekly podcast. “So the amount of energy we would need to generate a power station would need to be hundreds or even thousands of times larger from every pulse.”

Nevertheless, this yield is an improvement by a factor of eight over experiments conducted earlier this year, and puts NIF on the cusp of sparking fusion, the team said in .

“It’s literally held together for as long as it takes to explode,” said Chittenden. “What we’re trying to achieve is a plasma state very much similar to the centre of the sun… and we can’t hold that pressure together for very long.” The pressure of the hydrogen was orders of magnitude higher than what has previously been achieved in any laboratory, he said.

Not only is this a step towards clean nuclear power, it could also lead to physics experiments that help us understand the most extreme locations in the cosmos and the seconds after the big bang. Researchers at NIF are now planning the next round of experiments in the hope of reaching ignition.

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Topics: Energy / nuclear fusion technology