Scientists and engineers near the English city of Oxford have set a nuclear fusion energy record, they announced Thursday, bringing the clean, future-proof energy source another step closer to reality.
Using the Joint European Engine (JET) – a huge donut-shaped machine known as a tokamak – scientists were able to sustain a record 69 megajoules of fusion energy for five seconds, using just 0.2 milligrams of fuel.
Nuclear fusion is the same process that powers the Sun and other stars, and is widely viewed as the holy grail of clean energy. Experts have worked for decades to perfect the highly complex process on Earth, and if they did, fusion could generate massive amounts of energy with a small input of fuel and emit zero carbon that warms the planet in the process.
The scientists fed the tokamak with deuterium and tritium, two variants of hydrogen likely to be used by future commercial fusion plants.
To generate fusion energy, the team raised temperatures in the machine to 150 million degrees Celsius, about 10 times hotter than the core of the sun. This intense heat forces the deuterium and tritium to fuse together and form helium, a process that in turn releases enormous amounts of heat.
The tokamak is lined with powerful magnets that hold the plasma. The heat is then harnessed and used to produce electricity.
This is the last experience of its kind for JET, which has been operating for more than 40 years. Its latest trial – and new record – is promising news for newer fusion projects, said Ambrogio Fasoli, CEO of EUROfusion, the consortium of 300 experts behind the trial. He pointed to ITER, the world’s largest tokamak being built in southern France, and DEMO, a machine set to follow ITER with the aim of producing a greater amount of energy, like a prototype of a fusion plant.
“Our successful demonstration of operational scenarios for future fusion machines such as ITER and DEMO, validated by the New Energy Registry, instills greater confidence in the development of fusion energy,” Fasoli said in a statement.
United Kingdom Atomic Energy Authority
View of the Torus Hall, where the JET tokamak machine is located.
While fusion energy will be a game-changer for the climate crisis — caused primarily by humans burning fossil fuels — it is a technology that will likely take many years to be commercialized. By the time it is fully developed, it will be too late to use it as a major tool for tackling climate change, according to Aneeqa Khan, a research fellow in nuclear fusion at the University of Manchester.
There are still countless challenges. Khan points out that the team used more energy to carry out the experiment than was generated, for example.
“This is a great scientific result, but we are still a long way from commercial fusion. Building a fusion power plant also involves many engineering and materials challenges,” she said. “However, investment in nuclear fusion is growing and we are making real progress. We need to train a large number of people and equip them with the necessary skills to work in this field, and I hope that the technology will be used in the last half of the century.
The record was announced on the same day that the European Union’s Copernicus climate and weather monitoring service confirmed that the world had exceeded the global warming threshold of 1.5 degrees Celsius over 12 months for the first time.
Scientists are most concerned about long-term temperature rises above this limit, but it is a symbolic reminder that the world is heading towards a level of climate change that it will struggle to adapt to.
Climate science shows that the world must cut its greenhouse gas emissions by nearly half this decade and reach net zero emissions by 2050 to prevent global warming from escalating to catastrophic levels. This means a rapid transition away from fossil fuels, such as coal, oil and gas.