Inside the JET tokamak – plasma is visualized on the left. The word tokamak, a Russian compound of the words “toroid” and “magnetic coil”, is part of a reactor in which nuclear fusion takes place.
The hottest place in our solar system is not the sun, as you might think, but a car near a village called Culham in south Oxfordshire. Located in a huge hangar, this is a fusion experiment called JET or Joint European Torus. During operation, the temperature here can reach 150 million degrees Celsius – ten times more than in the center of the Sun. On December 21, 2021, JET set a new record by producing 59 megajoules of sustainable energy in a process called nuclear fusion.
59 megajoules is not that much, enough for three cycles of a household dryer. However, as far as humans are concerned, proof that fusion works really matters a lot. Fusion produces energy by fusing atomic nuclei together, unlike what happens in all nuclear power plants where the nuclei are split by nuclear fission. Once used on a commercial scale, fusion can generate so much energy from such a small amount of raw materials that it can solve all of humanity’s energy problems in one fell swoop – among other things.
The JET division has been based in Culham since 1983. Thermonuclear fusion as a concept has been of interest to the scientific community since the 1960s, when Soviet scientists discovered its potential.
Professor Stephen Hawking was once asked what problem he would like scientists to solve by the end of the 21st century. “I want fusion to be a practical source of energy,” he replied. “This will provide an inexhaustible supply of energy without causing pollution or global warming.”
However, JET currently requires more power to run than it produces. The net energy gain – the holy grail of fusion because it releases more energy than it consumes – has eluded JET scientists so far. Actually, all other scientists work in this area.
Up close, the JET looks very good. While the experts at the Callum Fusion Energy Center (which is overseen by the UK Atomic Energy Agency) are familiar with every inch of the massive machine, to the untrained eye it is confusing asymmetrical rebar, support beams, cages, ladders, wires, cables, pipes , pipes, switches, monitors, valves, plugs, scaffolding, walkways and steel slides.
Outside, it has a height of 12 meters and a diameter of more than 7 meters. The whole machine weighs 2800 tons. Hidden somewhere in the center is a donut-shaped (or ring) container called a tokamak. (Based on an early 1950s Soviet design, “tokamak” is an abbreviation derived from Russian phrases meaning “toroidal chamber” and “magnetic coil”.)
While fusion reactors are much safer than nuclear power plants (more on that later), Coolum’s reliability and reliability are understandable. The JET itself sits behind a meter-thick, 20-meter-high concrete barrier that shuts down during operation, primarily to contain dangerous neutrons produced by fusion reactions. Entry is through a security turnstile and each visitor is measured with a dosimeter for radiation levels upon entry and exit.
First put into operation in 1983, JET has produced fusion pulses on tens of thousands of different occasions. At the end of next year, after 40 years of service, it will be the swan song before the final retirement. Scientific understanding and much of the proven technology will be used in next-generation tokamak synthesis projects. The International Thermonuclear Experimental Reactor (ITER) is currently under construction near Marseille in southern France, a joint project of 35 countries, including the UK. There are also plans for a British project called Spherical Tokamak Energy Production or STEP. On 3 October, his location was confirmed as the location of Seaburton Power Station in Nottinghamshire.
JET is led by Professor Ian Chapman, Chief Executive of the UK Atomic Energy Agency. He predicts that ITER will start receiving net energy gains in the late 2040s. When asked when nuclear fusion could produce cost-effective energy on a commercial scale, he was less precise.
Phoenix is ​​the name of Culham’s first major fusion project. Phoenix itself is a “mirror machine” and uses magnetic mirrors to control the behavior of charged plasma in linear (rather than circular) fusion devices.
“This is an immeasurable issue and a lot depends on energy dynamics, government policies and what happens to carbon prices,” he told National Geographic. “I never answer this question. I always quote Lev Arsimovich, one of the founders of the tokamak. He was asked this question at a press conference in the Soviet Union in the 1970s, and he replied: “When humanity needs it, maybe and no. long before that. “I think it’s still true.”
With the fuel crisis now dominating the UK headlines, Chapman notes that the energy we produce using modern methods will eventually become so expensive that governments and private companies will have to invest extra money and take over greater risk to use thermonuclear fusion. He explained how JET’s initial investment began in the late 1970s, after the global oil crisis. Now the energy instability caused by the war in Ukraine could become the same catalyst for nuclear fusion.
“Energy policy has been carried out for ten years,” he added. “Nowhere in the world is there a parliament running on a ten-year time frame, so unfortunately a market shock usually triggers energy action.”
“The ultimate goal is to apply this research to deuterium (heavy hydrogen) bound nuclei, which are almost infinite in the ocean, to generate energy.” Cards taken during a press tour at Rohm Labs, where thermonuclear experiments were carried out.
Even with significant investment, there are still very high hurdles to overcome: technical issues such as fuel performance and reactor maintenance, as well as political issues, although the Americans, Europeans, Russians, Chinese, Japanese and Australians have expressed enthusiasm for the idea.
The same as the British. In October 2021, the Department for Business, Energy & Industrial Strategy published its strategy on nuclear fusion. In October 2021, the Department for Business, Energy & Industrial Strategy published its strategy on nuclear fusion. In October 2021, the Department of Business, Energy and Industrial Strategy released its nuclear fusion strategy. In October 2021, the Ministry of Business, Energy and Industrial Strategy released its merger strategy. It was noted that this form of energy would be plentiful, efficient, carbon-free, safe, and would produce radioactive waste with a much shorter lifespan than current nuclear power plants.
Arthur Turrell is a former plasma physicist at Imperial College London, and author of a 2021 book, The Star Builders: Nuclear Fusion & the Race to Power the Planet. Arthur Turrell is a former plasma physicist at Imperial College London, and author of a 2021 book, The Star Builders: Nuclear Fusion & the Race to Power the Planet. Arthur Turrell is a former plasma physicist at Imperial College London and author of the 2021 book Star Builders: Nuclear Fusion and the Race for Planetary Energy. Arthur Turrell is a former plasma physicist at Imperial College London and author of the 2021 book StarMakers: Fusion and the Race to Power Earth. “Managing fusion to produce energy is the greatest technological challenge we face as a species,” he said. He explained that fusion reactors or “star machines” are indescribably complex, with tens of millions of individual parts.
So how does nuclear fusion work? This is the fusion of light nuclei with the formation of heavier nuclei with the simultaneous release of a huge amount of energy. This is what happens among stars like our sun that provide the energy that drives the universe. Importantly, this is the opposite of nuclear fission, a process used in nuclear power plants, which releases large amounts of energy when atomic nuclei are split into smaller nuclei.
Despite the sun, people are currently experimenting with two main methods of synthesis. JET, for example, uses so-called magnetic confinement fusion: two isotopes of hydrogen — deuterium and tritium — are heated to temperatures up to 150 million degrees Celsius, turning into a charged gas called plasma, enclosed in a ring-shaped current. brand, and controlled by a strong magnetic field. Deuterium and tritium fuse together to form helium and high-speed neutrons, releasing huge amounts of energy in the process – 10 million times more energy per kilogram of fuel than burning fossil fuels. As Turrell neatly explained, the equivalent of Olympic pool water would have a mass of deuterium-tritium fuel that would be more than the energy used by the entire Earth in a year.
Another fusion method, called inertial confinement fusion, uses high-power lasers to heat and compress deuterium and tritium inside a capsule. One of the major advances in this area is the National Ignition Facility (NIF) in California.
Of course, proving that fusion works is not the same as using it commercially. In the past, there was a joke among nuclear physicists: “The merger will take place in 30 years, and it will always be so.”
As soon as the confluence began to gain strength, this old witticism began to lose its strength. Fusion pioneers around the world are stealing the solar power generation process on Prometheus missions and replicating it on Earth. It is estimated that there are currently more than 100 experimental fusion reactors in the world, some under construction and others already in operation. As Turrell explains, “Public and private, big and small star machines take off.”
There are four major facilities in the UK alone – all currently in Oxfordshire: in addition to JET, there are Tokamak Energy, First Light Fusion and General Fusion.
A screen in Culham showing telemetry data from a record-breaking 56,000 J fusion experiment in 2021.
Ultimately, they all run on clean energy. Ask Turrell where he thinks this could happen first, and his eye will be drawn to California’s National Ignition Plant, which has already achieved a 70 percent net energy gain. He suggested that they “adjust a little” to reach 100%.
Chapman is happy with all this competition. “It’s all good for society,” he said. “We all want a merger to happen. We have to try many different options. Spend more money, take more risks.”
He compared these noble efforts to the space race between the United States and the Soviet Union in the 1960s. “When Kennedy gave his speech, it was incredible that in seven years people would be walking on the moon. If you have the political imperative to spend money very quickly, you can achieve incredible achievements. America spends more than 4% of GDP on the space race.”
Fusion enthusiasts believe that this sustainable form of energy could eventually replace all of our nuclear power plants. There are many obvious benefits.
First, there is an adequate supply of fuel. “Deuterium is very common,” Turrell writes in his book. “Tritium… can be made from another extremely common element: lithium. Advanced fusion power could provide humanity with clean energy for millions or even billions of years.”
Chapman agrees: “All the fuel I need for the rest of my life is water to fit in a bathtub and lithium to fit in two laptop batteries. That’s all I need for 60 years.” inadequate. One solution that ITER is exploring is to create tritium from lithium using what they call a fertile blanket. They will become part of the reactor wall and cause the neutrons to react with the lithium in the shield to form more tritium. If this works, power plants could eventually become tritium self-sufficient.
The mere mention of the word “atomic” inevitably frightens many energy consumers. Chapman understood why, but quickly dismissed the idea, pointing out that, compared to fission, fusion was actually risk-free. This is the second obvious advantage.
“There is enough fuel at the nuclear plant for two to three weeks,” he said. “If something really unusual happens, like a high tide or an earthquake, this fuel will last for two to three weeks. You cannot control it. I want it to stop, it stops. Physically, there can be no chain reaction process. I’ve spent my 20 year career trying to keep the damn thing going.”
Fusion proponents hope that this energy source, which is often said to use the same energy production principles as our sun, will replace less efficient clean energy sources and even provide long-term energy for space travel.
Although those working on fusion are clearly biased, they all agree that this form of energy is vital in an energy-hungry world. Renewable energy sources will continue to play an important role, but this may not be enough.
“We want to make the world a better place and make sustainable energy accessible to everyone,” Chapman said. “We should use renewable energy sources wherever possible. But they don’t work everywhere – if you don’t have access to sunlight or wind, for example. Fusion is everywhere and fuel is readily available. It eliminates energy poverty; it gave us energy equality “It means we are ending the war on energy. It will be a revolution of this magnitude and such an important part of the future energy mix.”
He believed that nuclear fusion would revolutionize the world like the industrial revolution. Turrell went even further, suggesting that this form of energy could eventually power spacecraft that would eventually carry humans on interstellar travel. “Fusion rockets are humanity’s best hope as they travel to the far reaches of space,” he told National Geographic.
Back in the hangar at Culum, JET sat idle, waiting for the next experiment. Before it is finally decommissioned at the end of 2023, it will conduct several more fusion experiments, mainly representing the new ITER facility.
Meanwhile, he lay like a sleeping dragon. Once he wakes up, you’d better keep your distance. When a dragon exhales fire, its temperature is 150 million degrees.