Published on behalf of Tokamak Energy.
Power from nuclear fusion has today been shown as possible on a smaller scale than expected, paving the way for rapid development of a clean, base-load energy source. In a paper published in the journal Nuclear Fusion, Dr Alan Costley, a scientist working for Oxfordshire-based Tokamak Energy shows the point at which more energy is generated than used is only weakly linked to the size of the reactor, contradicting traditional assumptions that have steered worldwide research efforts towards larger devices until now.
Fusion energy is the ultimate clean source of power, with virtually unlimited fuel. Fusion takes place within a hot plasma, a state of matter at high pressure and over a hundred million degrees in temperature. The tokamak, a toroidal shaped magnetic bottle, is the best performing device by far for controlled fusion.
Today’s results open up a fresh path to fusion power by showing tokamaks do not have to be huge to generate power. Costley took years’ worth of data that tell us how tokamak fusion performance changes with variables such as size, current and magnetic field, and combined this with known ‘operational limits’ which dictate the plasma conditions required for the best results. He found the surprising result that performance of tokamaks doesn’t depend on size. Fusion reactor development can now proceed much more rapidly thanks to such scaling down, potentially helping the first compact fusion pilot plants to be ready to produce electricity for the first time within the next decade.
Dr David Kingham, Chief Executive of Tokamak Energy, said “This work by Dr Alan Costley is further validation for our approach of accelerating the development of fusion power; our earlier Nuclear Fusion paper looking at small scale fusion reactors published in 2015 is the most downloaded paper in the history of the journal and has set in motion this fundamental shift in tokamak fusion science. We will make fast progress by keeping devices small, using the efficient spherical tokamak shape and by using the latest generation of high temperature superconductors to generate the strong magnetic fields necessary while reducing the energy input. This work adds further weight to our ideas for compact 100MW fusion power modules. They are shown to be feasible from a physics perspective and are now primarily a materials and engineering challenge.”
Dr Costley’s paper indicates that future tokamak power plants will not need to be as large as ITER, It also strengthen the case for research on tokamaks. There is no doubt that the technologies and knowledge base being developed for ITER will be important to accelerate the development of more compact tokamak devices.