Undeterred by taunts that fusion always seems to lie 50 years in the future as a commercial energy source, a growing programme of research is aimed at taming the nuclear reaction that powers the sun and the H-bomb. It releases energy by combining light elements, in contrast to the atom-splitting fission process that drives current nuclear power stations. Fusion research falls into three different camps. One is the traditional “big science” approach — exemplified by ITER, a project to build an experimental fusion reactor at Cadarache in France. Second is a wave of start-ups whose ambition is to deliver power more quickly and less expensively than the big public projects. These companies are using the same hot fusion approach, forcing atomic nuclei together at extreme temperatures and pressures.
The ITER cryostat, designed to house super-conducting magnets and deliver a super-cool fusion environment
Lurking out in left field is a third way — utterly different in that it claims to release fusion energy in much more moderate conditions, close to room temperature. This approach, a successor to the “cold fusion” experiments carried out by Stanley Pons and Martin Fleischmann in 1989 and now usually called “low energy nuclear reaction” or LENR, is ignored by the scientific mainstream but making progress according to devotees in labs around the world.