If Europe is to meet its climate targets, work on developing and expanding renewable energy sources needs to go ahead at full speed. But this changeover brings its own challenges. Because the output of solar and wind farms can only be controlled to a limited extent – in other words, if the sky is overcast and the wind is not blowing, there is nothing that can be done about it – solutions are needed that can guarantee grid stability and security of supply in the future.
One approach is to create our own tiny suns here on earth that can provide us with a reliable supply of electricity when the renewables are out of action. These are the fusion reactors that we have invested billions of euros in developing. In power plants of this kind, two atomic nuclei could be combined at a temperature of around 150 million degrees Celsius to form one single nucleus. Deuterium and tritium would be used to produce helium. This process releases one neutron and its energy is used to heat water that drives turbines to generate electricity.
Nuclear fusion is in some respects the opposite of classic nuclear fission. It is not just that the process goes in the other direction – fusing atomic nuclei instead of splitting them – but also that the impact on the environment and on society are completely different. While nuclear fission involves significant risks and produces large quantities of radioactive waste, nuclear fusion is comparatively clean. And according to the scientists, it is impossible for the fusion process to get out of control and lay waste to vast swathes of land. We do not even need to worry about terrorist attacks: “The people living near the power station would not have to be evacuated.”
This promise was made by Bernard Bigot, who has been director-general of ITER since 2015. ITER stands for International Thermonuclear Experimental Reactor and is the world’s best-known fusion experiment. The objective of the test reactor in Cadarache in France is to demonstrate not only that the technology is controllable, but also that it can produce more energy than it uses. No one has yet succeeded in doing this. It is not an exaggeration to say that the entire industry is watching this project closely. The future of fusion energy depends primarily on the success of ITER.
However, the project’s immediate history does not give cause for optimism. Originally, the power plant was to cost five billion euros and come into operation in 2016. The cost quickly tripled, while the completion of the plant was delayed until 2019. The investors have now had to come to terms with a budget of 20 billion euros and an expected go-live date of 2025.
However, there is absolutely no guarantee that these figures will not change. One of the project’s main challenges is that a large number of players are involved, including the USA, Russia, China, South Korea, Japan, India, and the EU, all of whom want to have a say in what happens and to benefit from the results. There is also a whole raft of technical problems to overcome and the solutions still seem a very long way off. The most fundamental of these was recently summed up by nuclear researcher Michael Dittmar in a report for the German Green Party. No one yet knows what material should be used for the internal wall of the vacuum vessel where the nuclear reaction will take place. The reason for this is both simple and astounding: there is simply no material available that can permanently withstand the heat needed for nuclear fusion.
Another unanswered question is where the tritium, which is one of the two main ingredients of the fusion process, will come from. The researchers’ relatively modest demand for tritium is currently met by nuclear (fission) power plants, but these are becoming fewer and further between. According to Dittmar, fusion reactors may have to produce their own tritium in the future. However, the theories about how this could be done are still just that: theories. The industry is many years away from a practical, financially viable process.
This leads us to the main criticism made by opponents of fusion power plants. Even according to the most optimistic schedules, the first reactors could only begin delivering electricity to the grid in 2055 at the earliest. Therefore, they could not make any contribution to decarbonization or to climate action in the short term. But in the long term, they would provide a reliable supply of carbon-neutral electricity, particularly when the weather conditions prevent wind and solar farms from meeting our power needs.
The German business newspaper Handelsblatt has calculated that by 2035 the EU will have invested a total of around 20 billion euros in ITER. Germany is, of course, responsible for part of these investments and also spends another 137 million euros every year on its own research into nuclear fusion. The massive uncertainties involved and the slow pace of development raise the question of whether the money would not be better spent elsewhere. For the Greens at least, the situation is clear. A resolution by the parliamentary party stated: “In the future national energy research program, no more public money must be invested in research into nuclear fusion, transmutation, or generation IV reactors.”
Naturally ITER director-general Bernard Bigot sees things differently. “I am firmly convinced that we cannot rely on wind, solar, and hydropower alone. We need a complement to them, a form of energy that can be produced consistently on a large scale. The major benefit of nuclear fusion is that it has no harmful effects on the environment or the climate. The potential advantages are so substantial that in my view it is worth being patient.” The German Federal Ministry of Education and Research is also committed to the ITER project: “From Germany’s perspective, the growing global demand for energy requires research into a wide variety of options for our future energy supply and an openness to new technologies.”
In overall terms, it seems unlikely that a project which has already been the recipient of so much funding would simply be put on ice. And who knows? Perhaps nuclear fusion really will be one of the energy sources of the future. Just not the future that everyone is currently interested in, but the one after that.