Molten salt reactor for nuclear waste planned in Dresden, Germany

A group at the Dresden University of Technology is preparing DEMO, an experimental 50 MW molten salt reactor designed to process spent nuclear fuel right where it is produced or stored. If the project succeeds, Germany could, according to the researchers' estimate, save up to 50 billion euros that would otherwise go into finding and building a deep geological repository.

How it is supposed to work

Conventional reprocessing relies on complex chemical processes that extract reusable materials from fuel elements. DEMO avoids these risky operations: highly radioactive waste, including spent fuel and vitrified materials, would be added directly to the molten salts. This is transmutation without fuel reprocessing.

Inside the reactor, the heavy atomic nuclei of the waste would be bombarded with neutrons and split into lighter elements. Most fission products would decay to a level safe for nature within a few decades rather than millennia. The remainder would consist mainly of short-lived radioactive isotopes, and, as the researchers suggest, it would not have to meet storage requirements as strict as those that apply today under German law.

Energy, medicine and fusion research

According to the researchers' calculations, the spent fuel stored in Germany would be enough to exceed the country's annual electricity consumption 300 times over. Besides low-carbon heat, such a reactor could produce important medical radionuclides for cancer treatment, as well as data for cutting-edge fusion research.

Timeline, money and sites

Total public investment in the project is estimated at 1.95 billion euros. Developing and building the reactor would take five years, followed by a twenty-year operating period. The German authorities are already considering three possible sites in Saxony: the VKTA research campus in Rossendorf and two large industrial transformation hubs in Lusatia, Schwarze Pumpe and Boxberg. If the project succeeds, it is to be followed by commercial transmutation plants supplying electricity to the grid.

Around Prague, based on reporting by osel.cz