The tamed fire of the sun as an inexhaustible source of energy

Dhe idea sounds great: if the sun’s fire could be tamed in the laboratory, mankind would have an inexhaustible source of energy at its disposal. Because just one gram of fuel – the hydrogen isotopes deuterium and tritium – would provide as much energy in a future fusion reactor as is produced by burning eleven tons of coal, but without polluting the climate with carbon dioxide emissions. There is also no need to worry about a shortage of fuel. After all, deuterium can be obtained from water and tritium via a nuclear reaction from lithium. Since no long-lived radioactive waste would be produced, the problem of final disposal would not apply. Even an accident like that in a nuclear power plant would not be to be feared in a fusion power plant.

So is nuclear fusion the ideal energy source to satisfy the world’s unrestrained thirst for energy in the long term and to protect the global climate from collapse? This question was asked on Tuesday afternoon by Constantin Häfner from the Fraunhofer Institute for Laser Technology ILT in Aachen, Peter Leibinger from the high-tech company Trumpf, Vinod Philip from Siemens Energy and Tim Luce, scientific director of the international fusion reactor under construction in Cadarche in southern France.

Experimental platforms for nuclear fusion implementation

“The planning and construction phase is behind us, now we are assembling all the components of ITER,” said Luce. But the scientists, technicians and engineers of the seven ITER partners – Europe, Japan, Russia, China, South Korea, India and the USA – are pressed for time. In just four years, a hydrogen plasma should ignite in Cadarche for the first time and tritium and deuterium nuclei should fuse together in 2035. “ITER will then deliver 500 megawatts of fusion energy, ten times the heat output used.” Peak is convinced that the massive project will succeed. Laboratory tests like JET at Culham, a smaller version of ITER, would have shown that nuclear fusion works. ITER would pave the way for a fusion power plant. This could then be operational by mid-century and provide clean electricity.

But how big is the chance for nuclear fusion in the energy market? For Vinod Philip, this mainly depends on how soon fusion power plants will be available. “The time window is comparatively small, because the expansion of renewables is progressing rapidly.” In its most recent report, the International Atomic Energy Agency (IAEA) predicts that nuclear energy, which also includes nuclear fusion, will have a ten to twelve percent share of the energy market by 2050 . For wind power and solar energy it is even up to 80 percent. “So we need nuclear fusion as soon as possible.”