British scientists have just set a record in the field of nuclear fusion. We are (a little) closer to ensuring clean energy

Nuclear fusion is the same process that powers the Sun and other stars and is seen as the holy grail of clean energy. Experts have been perfecting this highly complex process on Earth for decades, and if they succeed, fusion could generate huge amounts of energy with small amounts of fuel and emit no planet-warming carbon.

Scientists and engineers in the English city of Oxford announced this week that they had broken a record in the field of nuclear fusion energy, bringing the source of clean, future energy closer to reality.

Using the Joint European Torus (JET) – a huge A-shaped machine donut Known as a tokamak – scientists preserved a record 69 megajoules of fusion energy for five seconds, using just 0.2 milligrams of fuel. This is enough to supply approximately 12,000 homes with energy during the same period of time.

Nuclear fusion is the same process that powers the Sun and other stars and is seen as the holy grail of clean energy. Experts have been perfecting this highly complex process on Earth for decades, and if they succeed, fusion could generate huge amounts of energy with small amounts of fuel and emit no planet-warming carbon.

Scientists fueled the tokamak with deuterium and tritium, different types 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 ten times hotter than the core of the sun. This intense heat forces deuterium and tritium to fuse and form helium, a process that in turn releases enormous amounts of heat.

The tokamak is covered with powerful magnets that retain 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. Their latest experiment – and new record – is promising news for new fusion projects, said Ambrogio Fasoli, CEO of EUROfusion, a consortium of 300 experts behind the experiment. Fasoli 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, as a prototype for 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.

While nuclear fusion energy may be a game-changer for the climate crisis – which is caused primarily by humans burning fossil fuels – it is a technology that will take many years to commercialize. When it is fully developed, it will be too late to use it as a primary tool to combat climate change, according to Aneeqa Khan, a nuclear fusion researcher at the University of Manchester.

Moreover, many challenges remain. Khan noted, for example, that the team used more energy to carry out the experiment than was generated.

“This is an excellent scientific result, but we are still far from commercial fusion. Building a nuclear fusion power plant also involves many engineering and materials challenges,” he noted. “However, investment in nuclear fusion is increasing and we are making real progress. We need to train large numbers of people and equip them with the necessary skills to work in this field, and I hope the technology will be used in the second 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 surpassed the 1.5°C global warming threshold for the first time in 12 months.

Scientists are concerned about long-term temperatures rising above this threshold, but this represents a symbolic warning that the world is approaching a level of climate change that it will find difficult 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 reaching catastrophic levels. To achieve this, a rapid transition away from fossil fuels, such as coal, oil and gas, is necessary.