CAGING A STAR
Inside ITER, the world’s biggest nuclear fusion experiment
A closer look inside ITER, the world’s biggest nuclear fusion experiment situated in the idyllic south of France.
From the small hill above Vinon-sur-Verdon, a village in southern Provence, you can witness two suns. Right before sunset, the effect is startling. One of the two suns has been blazing for the past four and a half billion years and is slowly setting. The other, an artificial sun, is being built by thousands of human minds and hands, and is – very slowly – rising. The last of the day’s rays cast a magical glow over the humongous construction site where the world’s biggest fusion reactor is being built.
The ITER (International Thermonuclear Experimental Reactor) project, a joint venture that involves 35 countries responsible for 85 per cent of global GDP, is the world’s greatest single scientific project. Nothing similar exists and never has – at least not with a common humanitarian goal at its core.
The researchers’ aims are clear: to prove that nuclear fusion, a process constantly taking place inside our Sun and other stars, can be utilised on Earth to produce electrical energy on an industrial scale and help humanity end its suicidal dependence on fossil fuels. From 1973 to the present, global energy usage has doubled. By the end of the century, it might actually triple. Seventy per cent of all carbon dioxide emissions pumped into the atmosphere are created through energy consumption; 80 per cent of all the energy we consume is derived from fossil fuels. The EU has formally pledged to start producing half of its electric energy from renewable sources by 2030. By 2050, the bloc’s members are planning to hoist themselves into a fully carbon-neutral society. But, given current trends, this seems like wishful thinking. Renewable energy sources simply won’t be enough for the task.
HI-TECH MEETS PLODDING DIPLOMACY
Nuclear fusion may not be a renewable energy source, but it is a relatively clean and safe way of generating cheap energy that just might be available to us all in around 30 years’ time. The process of fusion (as distinct from the nuclear fission that takes place in existing nuclear power plants) involves getting hydrogen nuclei, which would normally repel each other, so hot that when they collide, they fuse together to form helium.
The slight difference in mass between the two hydrogen nuclei and the helium atom is released as energy, according to Einstein’s famous equation E=mc2. Our Sun is a perpetual fusion factory – a gigantic burning ball of plasma fusing several hundred tonnes of hydrogen into helium each second, with heat and light the result.
Plans to build a fusion reactor have been around for so long that some members of the scientific community have come to treat the idea as a bit of a joke. For much of the ITER project’s lifespan, its progenitors have mostly been devoted to explaining the constant delays and endlessly spiralling costs. It was only after 28 July 2020, when the project’s leading men and women first addressed the public online, that the media really began to sit up and take notice.
In reality, however, the project is already 35 years old. The broad outline was put in place in November 1985, during the final stretches of the Cold War, at the summit in Geneva that brought together US President Ronald Reagan and Soviet General Secretary Mikhail Gorbachev. A contract regulating the implementation of the international research project was signed the following year.
Finding the right location took a long time; reaching a logistical and geopolitical consensus took even longer. More than a decade of technical studies, political bargaining and diplomatic fine-tuning was required before Saint-Paul-lez-Durance in idyllic Provence was finally agreed upon. The choice was finalised at the end of 2005 in Moscow. On 21 November 2006, the Elysée palace in Paris hosted the signing of the agreement on the construction of the world’s largest experimental fusion reactor. By that stage, scientists had been working full-blast for years. Technological advancement finally feel in step with diplomacy.
Six months later, the 181-hectare site saw the revvingup of the first construction machines. At the end of July 2020, the huge area, formerly occupied by an ancient oak forest, saw the start of the assembly of the tokamak – the ‘heart’ of the reactor, where the fusion experiments will take place – which is set to be completed in five years.
STAGGERING DIMENSIONS
From afar, the ITER project already betrays glimmers of its final appearance, but from up close, things don’t look quite so close to completion. The main worksite is a markedly sterile environment, where tremendous components are slowly and carefully slotted into place in almost total silence by 750-tonne cranes.
The view from atop the tokamak shell invites science fiction flashbacks. Initially conceptualised during the 1950s by the Russian physicists Ifor Tamm and Andrei Sakharov, a tokamak is the device in which fusion takes place. It uses powerful magnets to contain an extremely hot substance called plasma in a toroidal
‘The focus on our common goals always prevails. What this is really about is people’
or doughnut shape. Plasma is all-important to nuclear fusion. It is essentially a superhot, electrically conducting gas made up of ions and free electrons. What we call plasma is what 99 per cent of the ordinary matter in the Universe is made of, including the stars, our Sun and all interstellar matter. Down here on Earth, plasma can be found in televisions, neon lights and auroras. In a fusion reactor, it’s created by heating hydrogen gas and then controlled using powerful magnets. The magnetic field and the heat of the plasma enable fusion.
ITER’s enormous tokamak will ultimately weigh 23,000 tonnes, the combined weight of three Eiffel Towers. It will be comprised of a million components, in turn made up of ten million smaller parts. The entire supporting complex – ‘the lower base’ – of the reactor will weigh some 400,000 tonnes.
The tokamak’s magnets will be some of the largest ever created. Their staggering proportions – some of them will be up to 17 metres tall – dictates their being assembled on site in a special hall in which you could comfortably park at least ten of the biggest freight planes in existence. The various elements are being assembled slowly and carefully – every millimetre counts.
The complexity of the endeavour is phenomenal. Compressed into a computer file, the ITER project takes up more than two terabytes. Every evening, the entire updated file is saved on more than 3,000 computers and 600 servers.
The complexity extends to the sheer number of people involved. ITER currently provides direct employment for some 3,000 people; the wider ITER network is comprised of around 4,500 companies with 15,000 employees from all over the globe. On account of the coronavirus pandemic, most of the project’s scientists, engineers and administrative staff are at home, reporting to their workstations twice a week. The physical workers – hundreds of them – are a different story. Most of them are housed in containers inside the vast complex. They work in shifts, almost without a halt in the construction process.
As for the local population, they accepted the news of the reactor’s construction with only a few fairly muted reservations. The ‘nuclear tolerance’ of the French population is markedly higher than it is in most other European countries. After all, about three quarters of the energy produced in France is derived from nuclear fission plants. The ITER project is also bringing a substantial amount of money to this part of Provence. Most of the international team is situated in three nearby towns: the prestigious university city of Aixen-Provence, the small and tranquil village of Vinon
‘We are standing on the cusp of proving once and for all that hydrogen fusion is a very real solution to the energy crisis’
sur-Verdon and the spotless, sleepy town of Manosque, where the ITER project’s international primary and secondary schools are located.
It’s in Manosque that I meet up with Chandramouli Rotti, an Indian physicist from Bangalore who now lives in a temporary home there with his wife, two daughters and both parents-in-law. ‘All my life I have been a plasma physicist,’ he says. ‘Given my education, there is no better workplace within my profession.’
The science he tells me, is actually the easy bit. ‘The hardest part is all the coordination and synchronisation,’ he says. ‘But in the end, the focus on our common goals always prevails. You know, all of this technology is just a tool. What this is really about is people. Doing my small part in this project has been an honour and a privilege.’
HUMANITY’S GOAL
‘Could you please explain to the average European citizen why it might be in his best interest to send part of his taxes your way?’ This is the question I put to ITER’s director-general, Bernard Bigot, as I sit with him in his sunny office overlooking the tokamak.
Bigot has already earned quite a reputation. Insiders seem to agree that it was his appointment in 2015 that invigorated the project, which some had begun to say was dead in the water.
‘Energy is life: biologically, socially, economically,’ he says, responding to my question with an assured grin. ‘What we need is a sustainable energy supply. When the Earth was populated by fewer than a billion people, renewable energy sources were sufficient to meet the demand. Well, not any more. Here we are now, eight billion strong and in the middle of a drastic climate crisis. There is no alternative but to wean ourselves off our current main power source. And the best option seems to be the one the Universe has been utilising for billions of years. Let me just add that hydrogen fusion is a million times more efficient than burning up fossil fuels. What we are trying to do here is very much like creating a small artificial sun on Earth. This fusion power plant will be in operation all the time. This sun, so to speak, will never set. Under total control, let me hastily add. And in absolutely safe circumstances.’
Part of the director-general’s job is to coordinate the project’s seven senior national partners and their often differing views. ‘Now that is truly no small feat, especially in these times,’ Bigot says, smiling. ‘I am tremendously lucky that all seven partners have grasped the unique opportunity provided by the construction of our reactor. We are standing on the cusp of proving once and for all that hydrogen fusion is a very real solution to the global energy crisis. Should we prove successful within this century, it will be a remarkable feat for everyone involved. Each of the partners seems quite aware that dropping the ball could easily mean the demise of the entire project.’ Allowing himself to wax just a tiny bit poetical, Bigot goes on to describe the enterprise as ‘an exceptional adventure and the holy grail of energy’.
His lofty aspirations are shared by other people working on the project. ‘For me, taking part in this project is my life’s work. Something bigger than me
and all of us. Something that just might save humanity,’ Javier Artola, 28, tells me. Hailing from Valencia, Artola studied nuclear fusion in Marseille and was then awarded a postgraduate scholarship at ITER by the Prince of Monaco. Almost as soon as he arrived, he says, he felt right at home and pretty much gave up on an external social life. ‘For me, fusion is something that only happens in a reactor,’ he says, laughing at what has apparently become something of a stock quip.
Artola is hugely enthusiastic about working in such an international environment. ‘The people here are so wonderfully knowledgeable,’ he says. ‘I’m picking things up all the time. But then that’s the very heart of science, isn’t it? To never – and I really mean never – succumb to complacency. We are looking for the perfect solution, while the engineers and machinists work with us to find optimal methods of implementation.’
MONEY AND TIME
The EU is footing the bill for 45 per cent of ITER’s evermounting costs. Each of the other participant countries are contributing a little over nine per cent. Initially, it was estimated that the entire venture would cost around €6 billion. Today, not even half way there, the total is being placed at closer to €20 billion, although more pessimistic commentators predict it will come to significantly more than that. One day’s delay costs about €1 million, the director-general tells me. Mounting costs have run parallel with changes to the timetable. In 2001, it was envisioned that the first batch of plasma would be produced in 2016. After Bigot took the helm, expectations were revised: first plasma in 2025, first fusion experiments in 2035.
‘We are not here to compete – we are here to cooperate. All of us must strive to master the temptation of domination,’ says ITER’s chief strategist Takayoshi Omae as we chat in his office at ITER headquarters. Omae’s expertise isn’t in science, but rather in the realm of dog-eat-dog international commerce. After helming a successful online company, he spent years advising companies in Asia. Today, he serves as the director-general’s managerial right hand and his entrepreneurial know-how has done much to revitalise the project. ‘ITER,’ he says, ‘is humanity’s project. Our task is to follow through on our promises. We have taken on a staggering responsibility, yet this can only motivate us more. What with the onset of the coronavirus pandemic, I haven’t had a free day in six months. But it is the only way. We must stick to the schedule, regardless of the circumstances outside.’
This schedule is complicated by a number of factors. During my time at the project site, I’m constantly told that achieving nuclear fusion in itself actually poses no tremendous scientific problems. But there are many supplementary issues. To trigger fusion inside a tokamak device, three key conditions must be met: a sufficiently high temperature (150 million degrees Celsius); a sufficiently high particle density within the plasma, to increase the chance of particles colliding and fusing; and the effective containment of the plasma within the tokamak for a sufficiently long time (it has a propensity to expand). The challenge is to create a situation where the amount of energy emitted by the
‘We are looking for the perfect solution, while the engineers work with us to find optimal methods of implementation’
fusion reaction exceeds the amount of energy needed to create and contain it. At present, the most energy ever created through such experiments can be chalked up to the JET reactor at the Culham Centre for Fusion Energy in Oxfordshire, which produced 16 megawatts of electrical energy. However, heating up the plasma to kick it all off required 25 megawatts of electrical energy. Harvesting the energy created by the fusion reaction is also a key part of ITER’s experiments. The idea is that heat will build up along the sides of the tokamak, where it will be captured by the cooling water circling the reactor. As in a normal power station, the heat will be used to produce steam and – by way of turbines and alternators – electricity. The water will eventually be released with the help of vast cooling towers. These have already been put in place and look like something you would find aboard the Battlestar Galactica.
The type of hydrogen fuel used in the fusion reaction is also of utmost importance. The process of hydrogen fusion inside our Sun is extremely slow. Although hydrogen atoms are constantly colliding with each other, it’s very rare for them to actually fuse together.
For this reason, two decades ago scientists began to focus on a way of speeding up the process by using two isotopes of hydrogen: deuterium and tritium.
The most common form of hydrogen, known as protium, contains a single proton; deuterium contains a proton and a neutron; and tritium contains a proton and two neutrons. Deuterium is present in seawater, but tritium is radioactive and unstable, and hence is extremely rare in nature. However, it can be produced synthetically. Nuclear fusion of deuterium and tritium (known as DT fusion) is preferable, because it occurs at lower temperatures than are required for deuterium–deuterium fusion and the reaction produces more energy.
At present the world’s tritium demand amounts to no more than 400 grams per year, but it’s exceptionally expensive: a single gram currently costs about US$30,000. Should nuclear fusion take off, demand would go through the roof – an 800 MW fusion plant is expected to consume 300 grams per day. The good news is that ITER’s reactor could potentially be used to produce its own tritium via a special lithium coating.
THE FUTURE OF FUSION
ITER, lest we forget, is an experimental reactor. It hasn’t been designed to produce electrical energy but rather to prove that it can be done. If all goes to plan, the decade of testing (2025–35) will be followed by the construction of power plants with a capacity of between 1 GW and 1.5 GW, and then, later, 4 GW (a typical nuclear-fission reactor produces around 1 GW of electricity).
The designs for such a power plant – called the Demonstration Power Station, or DEMO for short – were actually ready as far back as 2009. The tokamaks inside these fusion plants are planned to be even larger than the one at ITER. The vacuum chamber inside its reactors, where the plasma is created, is expected to have a volume of 2,200 cubic metres – almost three times more than the vacuum chamber in the test reactor, which has a volume of 840 cubic metres. Realistically, the moment when fusion-produced electrical energy starts coursing through powerlines and supplying our homes and businesses is still at least 30 years off. However, there are private fusion companies that are predicting that they will pull such a feat off within a decade – albeit on a much smaller scale. This might seem like incorrigible optimism, but right now, about 50 private fusion projects are under way, backed by some of the richest investors in the world, including Bill Gates and Jeff Bezos.
Of course, questions of safety are never far away. ‘True, the deuterium–tritium reaction is not a chain reaction, but does this allow us to say that fusion is completely safe?’ asks science journalist Michel Claessens in his book ITER: The Giant Fusion Reactor. His answer tilts towards optimism: ‘Despite some well-known problems, magnetic confinement fusion is undeniably a cleaner technology than nuclear fission since it will produce no long-lived radioactive waste and less waste overall. ITER has been designed to withstand all possible and conceivable accidents.’ However, Claessens goes on to say that the nuclearfusion community will nonetheless be forced to confront a range of new security challenges, because the DEMO reactors will be different from the tokamak being installed at ITER. But he remains convinced that the risk of accidents at industrial fusion plants will be essentially non-existent – in marked contrast to the risks inherent in the current nuclear-fission plants, as illustrated by the disasters suffered by the Chernobyl and Fukushima plants.
The fusion experiments that are taking place in the south of France are planned to have run their course by 2047. After that, the fusion process could finally be put to industrial use. The road is still long, but the global climate crisis is providing plenty of motivation to reach that goal as quickly as possible.