The Swedish Energy Agency, which falls under Sweden’s Ministry of Infrastructure, has awarded funding of $10.6-million to support the construction of a demonstrator small modular nuclear reactor (SMR) in the country. The funding has been granted to Swedish Modular Reactors AB, which is a joint venture between local companies Uniper Sweden and LeadCold.

LeadCold is a spin-off company from Sweden’s Royal Institute of Technology (abbreviated to KTH in Swedish), while Uniper Sweden is a subsidiary of the Germany-based international energy group Uniper. The two companies and KTH jointly announced in February last year that they would jointly explore the construction of a Swedish-designed demonstrator SMR.

The SMR design concerned is called SEALER, an acronym for Swedish Advanced Lead Reactor. It will use liquid lead as its coolant (instead of water, or gas, as used in alternative designs), and will be ‘passively safe’ – that is, if anything went wrong, the reactor would shut itself down, without any need for human intervention. The use of liquid lead coolant will allow for a very compact reactor.

However, liquid lead-cooled reactors have only ever been used by the former Soviet Union, which powered its seven ‘Alpha-class’ nuclear-powered attack submarines with such reactors. But the Alphas (a North Atlantic Treaty Organisation codename, as the Russians did not then release their official designations for their vessels) served for between only nine and 12 years before being decommissioned (the only exception had her liquid lead reactor replaced by a conventional pressurised water reactor).

Thus, the Swedish Energy Agency funding was to help build a non-nuclear electrically-powered test facility or prototype which would test and verify the systems and materials to be used in the construction of the actual SMR. This prototype would be to 1:56 scale and be located at Oskarshamn nuclear power plant. It was planned that it would start operating in 2024 and function for five years.

“The technology can eventually be developed into a cost-effective fossil-free base power and thus contribute to facilitating electrification for a transition to a fossil-free society,” stated the Swedish Energy Agency. The SEALER SMR was expected to be able to generate from 3 MWe to 10 MWe over a lifetime lasting from ten to 30 years. It could also be used to produce hydrogen. The reactors would be produced as sealed units and not need refuelling during their lifetimes. Once they had reached the end of their lives, they would be transported to a central recycling plant.