They started building it in 2006, and now with the installation of the last magnetic coil complete France has ITER, the world’s largest experimental fusion reactor. Along with the announcement, the power plant’s managers also said the reactor, which consists of 19 massive coils wrapped in ring magnets, will be able to start operating in 2039 according to plans.
The fusion reactor was created by the joint efforts of 35 countries, the initial budget was $5 billion (which eventually increased to $28 billion), and according to plans, it was supposed to be completed by 2020.
Scientists have been trying to use nuclear fusion to produce energy for about 70 years, but in practice, solving the problem safely is more difficult than theoretical physicists thought. The basic principle is the same as the one that works in the sun or any other star: under enormous pressure and high temperature, hydrogen atoms combine to form helium (they fuse, hence the name), and in the process, a huge amount of energy is generated. Moreover, without radioactive waste or greenhouse gases being by-products of the process. If nuclear fusion could be used reliably to produce energy, it would produce an almost unlimited amount of clean energy and solve many of humanity’s problems in one fell swoop.
The problem is that the conditions prevailing in the heart of stars, that is, to initiate and maintain the fusion process, are not a completely trivial task. The design of experimental reactors, including ITER, is a so-called tokamak, which heats plasma (one of the four states of matter, consisting of positive ions and negatively charged free electrons) in a doughnut-shaped reactor chamber with an extremely strong magnetic field. ITER uses the world's most powerful magnet for this purpose, 280,000 times stronger than the Earth's magnetic field.
In a reactor, the pressure at the core of a star cannot really be reproduced, so the fusion initiation is achieved by raising the temperature higher. In this way, ITER keeps the plasma at a temperature higher than the core of the Sun, which is very delicate to deal with – and the safe solution to this has caused the project to falter for many years and cost billions of dollars.
However, ITER has now reached an important stage, and it is possible to start testing the already completed reactor, so that, according to plans, it will start producing energy within 15 years. “As for the impact of technology on the current problems of humanity: we should not wait for nuclear fusion to solve them. This would not be wise,” said the ITER Director General.
