Five second blast of nuclear fusion can power a kettle for 19 hours
A UK-LED experiment has broken the world record for the amount of energy produced from nuclear fusion.
The Joint European Torus (JET) at Culham, Oxfordshire, has been operated by the UK Atomic Energy Authority (UKAEA) for 40 years and it ran for a final time in December last year.
Data from its swansong experiment revealed the system had created 69 megajoules of energy over the course of a five-second pulse. A total of 0.2mg of fuel was used and its output surpassed the previous record of 59 MJ set in 2022. The amount of energy created was enough to power a domestic kettle for about 19 hours non-stop, but less than was needed to maintain the experiment.
No fusion experiment has yet created a net gain of energy, but the incremental advances indicate that engineering improvements and tweaks to the process are making fusion more efficient.
Fusion energy is extremely expensive and difficult to produce as it requires heating hydrogen to 100 million degrees Celsius, ten times hotter than the centre of the Sun.
This process releases a huge amount of energy – pound for pound fusion releases almost four million times more energy than burning coal, oil or gas.
JET is now being decommissioned and has passed the baton of fusion experimentation to ITER, another Europe-wide consortium, which is being built in France. Both use spherical tokamaks, doughnut-shaped metallic caverns in which magnets force the atoms together and contain the plasma.
The magnets also allow the uber-hot plasma to levitate without touching the walls. The process can run for only five seconds; any longer and engineers worry the hostile conditions could cause the magnets to fail.
Fusion, unlike nuclear power stations, carries no danger of an explosion or a runaway reaction, because the process stops as soon as something is jeopardised or fuel runs out. The UKAEA is now focusing its efforts on STEP, a prototype fusion-energy commercial power plant being built in West Burton,
Notts, on the site of a defunct coal power station.
Experts hope to generate fusion energy sustainably and in a commercially viable way by 2040, and the ambition is for STEP to be the first in the world to do so. However, the engineering capability to achieve sustained fusion does not yet exist. Andrew Bowie, minister for nuclear and networks, said the latest milestone showed the UK and its collaborators were “closer to fusion energy than ever before... JET’S final fusion experiment is a fitting swansong after all the groundbreaking work that has gone into the project since 1983,” he added.
Prof Sir Ian Chapman, chief executive of UKAEA, said: “JET’S legacy will be pervasive in all future power plants. It has a critical role in bringing us closer to a safe and sustainable future.”
If the substantial technical obstacles can be overcome then fusion could solve much of the world’s energy woes, as it generates a huge amount of energy for very little fuel, requires no exploitation of finite natural resources and produces no greenhouse gas emissions.