More and more politicians and debaters are today expressing the view that we should invest more in a new generation of nuclear power that uses spent nuclear waste as fuel, one of which is the reactor physicist Janne Wallenius.

- Today there is no real generation four reactor in operation, there are some reactors that are a step on the road to generation four, says Janne Wallenius, who is a reactor physicist at KTH in Stockholm.

He himself is developing new reactors that will be able to use fuel from nuclear waste, and he hopes to build a first demonstration reactor in the UK in the mid-2020s.

Takes time to develop

But Fredrik Hedenus, an energy researcher at Chalmers University of Technology in Gothenburg, has made calculations of the time it takes to develop new energy systems.

Right now, Russia and China are at the forefront of the development of the fourth generation of nuclear power.

- Now let's say that China manages to build its first commercial reactor in 2030, well then you will have to run it for a few years to see that everything works. Then you build one more, then maybe we have two completed 2040, he says.

Wind turbines

Fredrik Hedenus compares with the first wind turbines that came in the 1970s and it is only now that wind power has grown really big.

- It's a similar thing we will see with generation-four. By the time we arrive at 2060 and 2070, we have probably expanded other systems to such an extent that hopefully we have solved the climate crisis. It is unclear if nuclear power can come in then, he says.

Cheap uranium

Another obstacle to the development of the nuclear power that recycles nuclear waste is that the ordinary fuel for today's nuclear power, uranium, is relatively inexpensive.

- The nuclear power industry is not really interested in the fourth generation of nuclear power because it would entail increased costs for producing nuclear fuel. The uranium has become very cheap and a lot of uranium has been extracted in Kazakhstan, says Janne Wallenius.

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