Scientists hail nuclear fusion breakthrough

Experts say results are 'landmark' and mark 'a huge step forward' for planet

Scientists have moved a step closer to developing power plants that run on nuclear fusion, which is the atomic reaction that powers the stars, after an experiment at a United Kingdom facility achieved record-breaking results.

Engineers at the Joint European Torus, or JET, in Oxford have more than doubled the previous energy record from a fusion reactor, achieving 59 megajoules of sustained fusion energy over five seconds, which is equivalent to 11 megawatts of power.

"These landmark results have taken us a huge step closer to conquering one of the biggest scientific and engineering challenges of them all," said Ian Chapman, who is chief executive of the UK Atomic Energy Authority.

Perhaps the most significant outcome of the experiment is that it validates many of the methods and technologies currently being incorporated into ITER, which is a nuclear fusion megaproject in France funded and run by China, the European Union, India, Japan, Russia, South Korea, and the United States.

While traditional nuclear power plants run by the process of fission, or the splitting of atoms, nuclear fusion reactors harness the energy produced when atoms are combined.

Functional nuclear fusion power plants would have many benefits over current sources of energy.Comparatively, small amounts of fuel would be needed to produce large amounts of energy in the fusion reaction, and some of the most effective fuels are abundant, including deuterium, which is an isotope of hydrogen.

The catch is that extremely high temperatures are needed to fuse atoms. In the JET facility, plasma is heated to 150 million C, which is around 10 times hotter than the center of the sun. To date, no facility has produced more fusion power output than electrical power input.

One of the major objectives for ITER is to be the first fusion reactor to break even and then eventually achieve a net-gain in power.

"A sustained pulse of deuteriumtritium fusion at this power level-nearly industrial scale-delivers a resounding confirmation to all of those involved in the global fusion quest," said Bernard Bigot, director general of ITER. "For the ITER Project, the JET results are a strong confidence builder that we are on the right track as we move forward toward demonstrating full fusion power."

Chapman said harnessing nuclear fusion energy would help address climate change, since the fusion reaction itself does not produce carbon emissions.

"Our world needs fusion energy," he said. "We're building the knowledge and developing the new technology required to deliver a low-carbon, sustainable source of baseload energy that helps protect the planet for future generations."

Once operational toward the end of 2025, ITER will be the biggest nuclear fusion facility in the world, with a plasma volume around 10-times more than the largest reactors running today.