THE “Holy Grail” of virtually limitless clean energy from nuclear fusion reactors is within reach after a series of major breakthroughs, scientists believe.
Boffins based in the US this week announced they had made groundbreaking headway in the international pursuit to create a mini Sun.
8The US team based in California were able to achieve a landmark net energy gain in their December experimentCredit: Reuters8The hydrogen capsule was blasted by 192 high-powered laser beams to mimick the conditions of the centre of the Sun8The JET nuclear fusion reactor near Oxford produced enough energy to power 10,000 homes8Boffins recreated the spark at the sun’s core by heating hydrogen to 150million degrees inside a magnetic coil8South Korea’s KSTAR sustained a 100m degree fusion reactor for 30 secondsCredit: New ScientistPhysicists have finally been able to achieve a net energy gain when carrying out a nuclear fusion experiment.
Researchers at the Lawrence Livermore National Laboratory in California revealed they were one step closer to their goal following a landmark study in early December.
Scientists explained they managed to “produce more energy from fusion than the laser energy used to drive it” – proving their plans could work on a global scale in the future.
The team put a minuscule amount of hydrogen into a capsule the size of a peppercorn, before firing 192 high-powered laser beams at it.
The powerful laser manages to mimick the conditions of the centre of the Sun, by sending the temperature soaring to more than three million degrees centigrade.
These forces cause the capsule to implode – seeing the hydrogen atoms fuse and incredibly release energy in the process.
The US team used 2.1 megajoules of energy to create the conditions for the reaction, and gained 2.5 megajoules return – an achievement known as fusion ignition.
The success of the £2.85bn experiment has been credited to “60 years of global research, development, engineering, and experimentation.”
Although experts are still years off the tech being used to power homes, the world is now one step closer to an energy revolution.
Researchers in the US had attempted the experiment “hundreds of times before” but had never gained more energy than was consumed.
Dr. Kim Budil, the director of the LLNL, described it as “one of the most significant scientific challenges ever tackled by humanity”.
And US energy secretary Jennifer Granholm echoed her comments, saying the study “will go down in the history books”.
Jeremy Chittenden, professor of plasma physics and co-director of the Centre for Inertial Fusion Studies at Imperial College London dubbed it “a true breakthrough moment”.
He added: “It proves that the long sought-after goal, the holy grail of fusion, can indeed be achieved.”
President Joe Biden has already pinned his hopes on a commercial fusion reactor being in place within 10 years.
Nuclear fusion is the process that powers the Sun and other stars.
Physicists have been trying to imitate it for decades to use as a source of near-limitless, clean energy.
It works by crashing pairs of atoms together — the opposite of fission which is the process used in nuclear power stations where atoms are torn apart.
It proves that the long sought-after goal, the holy grail of fusion, can indeed be achieved.Jeremy Chittenden
Fusion produces only small amounts of short-lived radioactive waste and, crucially, no greenhouse gas emissions.
The US already welcomed a significant step in cracking the process in November 2021, the Financial Times reports.
A Boston-based start-up demonstrated the use of a high-temperature superconductor to generate a much stronger magnetic field than a traditional tokamak.
Commonwealth Fusion Systems believes the discovery will enable it to make a more efficient fusion machine that will be more viable in the long-run.
The race to create clean energy has been hotting up in recent months, with boffins in South Korea successfully igniting an “artificial sun” burning at 100million degrees in September.
It scorched seven times hotter than the sun – and sustained the fusion reaction for 30 seconds.
The KSTAR researchers aim to increase that to five minutes – potentially paving the way for a commercial reactor that could keep going indefinitely.
“We usually say that fusion energy is a dream energy source – it is almost limitless, with low emission of greenhouse gases and no high-level radioactive waste – [but the latest breakthrough] means fusion is not a dream,” said Yoo Suk-jae, the president of Korea Institute of Fusion Energy said.
It marked yet another advance in the decades-long quest to crack technology that promises to solve the world’s energy needs.
In February, a UK-based team smashed the world record with sustained fusion at 150million degrees, retaking the lead in a global race that also involves China, the US and tycoons such as Jeff Bezos.
More than 4,800 scientists from the UK and across Europe work on the Joint European Torus, or JET, an experimental reactor in Abingdon near Oxford.
They announced the intense ring of fire contained in its magnetic coils – superheated to ten times hotter than the sun’s core – produced a world record 59 megajoules of energy.
Averaged over the five second burst, this works out at 11 megawatts, which is enough to power 10,000 homes.
That enormous energy output, double the previous record, was generated from just two thousandths of a gram of “heavy hydrogen” fuel.
Fusion reactors work by boiling the hydrogen into plasma, a state so hot even atoms can’t exist, and smashing protons together to form helium nuclei.
It is the same process that happens at the centre of every star including our sun – and also in H-bombs.
Fusion releases four times more energy by weight of fuel than nuclear fission – splitting heavy atoms like uranium – and four million times more energy than burning fossil fuels.
What’s more, the fuel is made from hydrogen, the most abundant substance in the universe, and theoretically there is no radioactive waste.
The challenge that has defeated scientists for the past 70 years is that no vessel can hold a substance at temperatures high enough for fusion to take place.
To solve this, JET uses a giant doughnut-shaped coil called a tokamak that creates a powerful magnetic field to keep the plasma from touching the sides.
LANDMARK FOR SCIENCE
The five second JET experiment still consumed more energy to create the fusion conditions than the energy it released, unlike the US team’s triumph.
But the ability to sustain a fusion reaction for so long remains a major advance as it proves it can be controlled.
Scientists hope they can scale it up for commercial use, potentially ending our reliance on fossil fuels and helping to reverse global warming.
“These landmark results have taken us a huge step closer to conquering one of the biggest scientific and engineering challenges of them all,” said Professor Ian Chapman, chief executive of the UK Atomic Energy Agency.
Dr Mark Wenman, of Imperial College London, said: “This means fusion energy really is no longer just a dream of the far future – the engineering to make it a useful, clean power source is achievable and happening now.”
Experts have high hopes for another project, the International Thermonuclear Experimental Reactor (Iter), a larger and more advanced version of JET based in the South of France.
It is due to be switched on in a couple years, and could generate ten times more energy than it uses.
China and India are among 35 nations collaborating on the project including the UK, the EU, Russia, Japan and the US.
The researchers are in a race, though – as other teams are making advances of their own.
Iter has been criticised as a grandiose waste of money bedevilled by bureaucracy.
The countries that can develop and wield this technology have the potential to see massive windfalls in terms of reliable and renewable energy, and the reduced vulnerability that comes with it.”Thomas Corbett & Peter Singer
Instead, national governments and even private companies have focused on their own schemes.
In December 2021, researchers in China revealed they had made a string of “immense” breakthroughs with their own tokamak fusion reactor, called EAST.
They were able to sustain a superheated loop of plasma at 70million degrees for more than 17 minutes, the longest ever period.
They did not generate any power, but it was a massive leap forward in the technology needed for keeping a reaction going.
And they are working to achieve ever higher temperatures and duration.
The speed and success of the Chinese project has already raised fears about its potential dominance in the field of nuclear fusion.
Analysts Thomas Corbett and Peter Singer say that China has huge ambitions for the sector and record-breaking advances to spur them on.
“The implications of this research, and this latest breakthrough by their indigenously designed and built device are immense,” they write in Defense One.
China has huge incentives to keep increasing its investment.
The country’s daily oil consumption is around 14.3million barrels a day, making supply worries a major headache for Communist rulers.
Nuclear Fusion – what is it?Here’s what you need to know…
Nuclear fusion is a process where two hydrogen nuclei (the central parts of atoms) are joined to create a single larger helium nucleus
This reaction releases huge amounts of energy
That’s because the helium nucleus has less mass than the two hydrogen nuclei combined
This “lost mass” is released as energy in the form of heat and light
Fusion is the process that powers stars such as our own sun
But kickstarting a nuclear fusion reaction on Earth is difficult
The problem is that all nuclei have a positive charge, and repel each other
To overcome this force, you need to make them hit each other at very high speeds – requiring high pressure and temperature
The goal is to sustain a fusion reaction that releases more energy than is used to start the reaction
If scientists can crack it, they could generate enormous and potentially unlimited amounts of clean energy
And China’s electricity grid is creaking under the strain of its quest for breakneck economic growth.
“Independence is thus a top priority for decision makers in Beijing”, the analysts say.
And cracking nuclear fusion could even spill over into the military domain in its race with the United States and other western powers.
The analysts write: “The development of viable fusion reactors will have many added advantages yet unforeseen in the military and civilian economy, much the same way that nuclear fission power did.”
EAST is a tokamak coil reactor like JET and Iter, based on a 1950s design from Russia.
China is also investing heavily in research into another approach, called inertial confinement fusion.
This is meant to initiate fusion reactions by compressing ions with high-power lasers, replicating the massive pressure at the sun’s core.
Currently under construction in Shanghai is the Station of Extreme Light, a facility for experiments with a 100-petawatt laser.
But China may not have it all its own way. Elsewhere other projects are also working furiously to crack nuclear fusion.
Meanwhile in the UK, five sites have been earmarked for the first prototype fusion energy plant.
Plans for the Spherical Tokamak for Energy Production (Step) and a final decision on its location are expected at the end of 2022.
The government has spent £222m on the Step programme so far and invested a further £184m at new fusion facilities at Culham Science Centre near Oxford and at Rotherham.
Super-rich investors like Jeff Bezos and venture capitalists have also backed an explosion of small fusion projects, using lasers or miniaturised versions of JET.
But not all scientists are convinced nuclear fusion can be as safe and clean as claimed.
Physicist Daniel Jassaby, who worked at the Princeton plasma lab, said a fusion reactor would be “far from perfect and in some ways close to the opposite”.
Writing in the Bulletin of the Atomic Scientists he said the process of nuclear fusion has the potential to produce radiation damage and radioactive waste – contrary to claims it is clean and safe.
He also says the “parasitic drain” of power needed to fuel fusion reactors renders means that they could “consume a good chunk of the very power that they produce”.
Fusion reactors have to be supplied with fuel made from fission reactors which he said implies a “perpetual dependence” on them.
And there is the potential for nuclear weapons proliferation through the “clandestine” production of plutonium-239.
But putting these concerns aside, nevertheless the effect of mastering nuclear fusion on our life could be staggering.
A glass of fuel has the energy potential of 1million gallons of oil and could generate enough to power a home for more than 800 years.
Corbett and Singer are clear about what is at stake in this race.
“The countries that can develop and wield this technology have the potential to see massive windfalls in terms of reliable and renewable energy, and the reduced vulnerability that comes with it.”
8America’s latest breakthrough marks a pivotal step in the mission to create the clean energy sourceCredit: Getty8China’s breakthrough with its ‘artificial sun’ reactor EAST has been described as ‘immense’Credit: Youku8The National Ignition Facility in Livermore, California, uses lasers to ignite nuclear fusionCredit: LLNL
Story Credit: thesun.co.uk