Nuclear Fusion Is Already Facing a Fuel Crisis

ITER is inching towards completion in the south of France. The International thermonuclear Experimental Reactor will be the largest device of its kind ever built, and the flag-bearer for nuclear fusion.

There are two types of hydrogen, called deuterium and tritium, that will be smashed together in a tokamak, releasing enough clean energy to power tens of thousands of homes.

The plan is at least that. The problem is that by the time ITER is ready, there might not be enough fuel left to run it.

ITER depends on a steady supply of both deuterium and tritium for its experiments. Deuterium can be taken from the water, but tritium is very rare.

According to the latest estimates, the amount of tritium on Earth is less than 40 pounds. Our best sources of tritium to fuel it and other experimental fusion reactor are slowly disappearing as ITER drags on, years behind schedule and billions over budget.

The tritium used in fusion experiments like ITER and the smaller JET tokamak comes from a very specific type of nuclear reactor called a heavy-water moderated reactor. In Canada, four in South Korea, and two in Romania, there are fewer than 30 left in operation, each producing 100 grams of tritium a year. India has plans to build more, but it is unlikely to make its tritium available to fusion researchers.

The whole point of nuclear fusion is to provide a cleaner and safer alternative to traditional nuclear power.

The second problem with tritium is that it decays quickly. It has a half-life of 12.3 years, which means that half of the tritium available today will be lost when ITER starts operations. The problem will only get worse after ITER is switched on.

The most expensive substance on Earth, tritium, was turned from an unwanted byproduct of nuclear fission that had to be carefully dispose of. It costs $30,000 per gram, and it is estimated that it will take up to 200 kilograms of it a year. Canada, which has the bulk of the world's tritium production capacity, refuses to sell it for use in nuclear weapons programs.