US breakthrough boosts clean energy hopes

US government scientists have made a breakthrough in the quest for unlimited energy and zero carbon by making a net energy gain in a fusion reaction for the first time, according to three people briefed on the preliminary results of a recent experiment.

Since the 1950s, physicists have sought to harness the fusion reaction that powers the sun, but no group has managed to produce more energy than the reaction itself consumes – a milestone known as net energy gain or target gain, which would help prove the process, could provide a reliable and plentiful alternative to fossil fuels and conventional nuclear energy.

The Lawrence Livermore Federal National Laboratory in California, which uses a process called inertial confinement fusion, which involves bombarding a tiny pellet of hydrogen plasma with the world’s largest laser, achieved a net energy gain in a fusion experiment at the last two weeks, people said.

While many scientists believe that fusion power plants are still decades away, the technology’s potential is hard to ignore. Fusion reactions do not emit carbon and do not produce long-lived radioactive waste, and a small cup of hydrogen fuel could theoretically power a home for hundreds of years.

The US advance comes as the world grapples with high energy prices and the need to quickly abandon the burning of fossil fuels so that average global temperatures do not reach dangerous levels. Through the Reducing Inflation Act, the Biden administration is investing nearly $370 billion in new low-carbon energy subsidies in an effort to reduce emissions and win a global race for next-generation clean technology.

The fusion reaction at the US government facility produced about 2.5 megajoules of energy, which is about 120% of the lasers’ 2.1 megajoules of energy, said people with knowledge of the results, adding that the data is still are being analysed.

The US Department of Energy said Energy Secretary Jennifer Granholm and Under Secretary for Nuclear Safety Jill Hruby will announce “a major scientific breakthrough” from the Lawrence Livermore National Laboratory on Tuesday. The department declined to comment further.

The lab confirmed that a successful experiment had recently taken place at its National Ignition Facility (NIF), but said analysis of the results was ongoing.

“Initial diagnostic data suggests another successful trial at the National Ignition Facility. However, the exact yield is still being determined and we cannot confirm that it is above the threshold at this time,” he said. “That review is in process, so publishing the information … before the process is complete would be inaccurate.”

Two of the people with knowledge of the results said that the power output was higher than expected, which damaged some diagnostic equipment, making analysis difficult. The discovery was already being widely discussed by scientists, the people added.

“If this holds true, we are witnessing a historic moment,” said Dr Arthur Turrell, a plasma physicist whose book “The Star Builders” [construtores de estrelas] shows the effort to reach fusion energy. “Scientists have struggled to show that fusion can release more energy than is applied since the 1950s, and the Lawrence Livermore researchers seem to have definitely and absolutely surpassed that decades-long goal.”

The $3.5 billion National Ignition Facility was primarily designed to test nuclear weapons by simulating explosions, but has since been used to advance fusion energy research. It came closest to the world’s net energy gain last year, when it produced 1.37 megajoules from a fusion reaction, which represented about 70% of the energy of lasers at that time.

At the White House’s launch of a new fusion energy strategy earlier this year, Congressman Don Beyer, chairman of the bipartisan fusion energy committee, described the technology as the holy grail of clean energy, adding: “Fusion has the potential to lift more citizens of the world out of poverty than anything since the invention of fire”.

Most fusion research takes a different approach known as magnetic confinement fusion, in which hydrogen fuel is held in place by powerful magnets and heated to extreme temperatures so that atomic nuclei fuse.

Historically, this science has been done by large, publicly funded laboratories such as the Joint European Torus in Oxford (UK), but in recent years investment has also flooded into private companies promising to deliver fusion power in the 2030s.

In the 12 months to the end of June, merger companies raised $2.83 billion in investment, according to the Fusion Industry Association, bringing total private sector investment to date to nearly $4.9 billion. billion.

Nicholas Hawker, chief executive of Oxford-based startup First Light Fusion, which is developing a similar approach to the one used at NIF, described the potential breakthrough as “game-changing”.

“It couldn’t be any deeper for fusion energy,” he said.