Temperatures of 150,000,000ºC are just one challenge the world’s first commercial nuclear fusion reactor faced

Projects of the year


The construction of the world’s first commercial nuclear fusion reactor must rank as one of the most technically ambitious projects ever. Sourcing unlimited energy from a constituent of seawater with virtually no dangerous waste would solve our energy problems at a stroke. But there is a big catch - the fusion reaction needs temperatures of 150,000,000ºC to work, which is 10 times hotter than the sun. The only way to do this with earthly technology is to suspend the reaction in space using powerful magnetic fields. This throws up a second big challenge - the huge coils generating the magnetic field work most efficiently when kept at a temperature of -269ºC. These coils are just a few feet away from the fusion reaction.

The downside of experimental fusion reactors has been that the energy needed to keep the reaction going has exceeded the amount it generates, rendering the exercise pointless. A consortium of six countries, including the EU, is betting £12.5bn that they can overcome this hurdle - the goal is to get 10 times more power out of this reactor than is put in. A huge international team, which includes consultant Atkins, is busy trying to make this a reality. After years of planning, the project has made it to site - although we will have to wait until 2020 to see if it works.