The UK Space Agency is funding two nuclear projects as part of the second phase of investment awarded through its £20m ($25m) International Bilateral Fund (IBF). Rolls-Royce and BWXT receive £1.18m for their collaboration on fission nuclear systems for space power missions. The University of Leicester and its international partners receive more than £783,000 to identify a range of mission opportunities for UK space nuclear power technologies. The collaboration also includes the development of hybrid power systems with existing US conversion technologies.

The phase two funding of £13m from the IBF was distributed among 11 projects. This followed a first phase announced last year, which provided funds of up to £75,000 each for 32 projects which then entered into a competitive process to receive phase two funding.

"We want to draw on the best global talent to push the boundaries of new technology such as AI and space nuclear power, enhance our homegrown space capabilities and catalyse investment into the UK economy," said UK Space Agency CEO Paul Bate. "The projects supported by our International Bilateral Fund champion the best of British innovation, while strengthening our ties with the wider space community."

The funding for Rolls-Royce Submarines and BWXT Advanced Technologies is for a project to "identify the optimum technologies for a fission nuclear system which balances flexibility to a range of space power missions and maximises performance whilst minimising programme and technical risk”.

This followed £2.9m awarded to Rolls-Royce from the UK Space Agency under the Lunar Surface Nuclear Power Contract and phase one IBF funding in 2023. This resulted in a demonstration in December 2023 of Rolls-Royce’s Space Micro-Reactor Concept Model, which showed how nuclear power could be used to support a future Moon base for astronauts.

This is part of a larger teaming agreement between Rolls-Royce and BWXT Advanced Technologies for collaboration and joint developments of new and novel nuclear applications in terrestrial, space and commercial maritime areas. BWXT said this further strengthens UK and US collaboration on first-of-a-kind space technology innovation as detailed under the Atlantic Declaration commitment. In an announcement made by UK Prime Minister Rishi Sunak and US President Joe Biden in June 2023, both countries pledged to study “opportunities for co-operation on space nuclear power and propulsion”.

Joe Miller, president of BWXT Advanced Technologies, said, “BWXT and Rolls-Royce share a commitment to creating and delivering nuclear energy systems to explore space, support global security imperatives and generate clean energy. Today’s announcement, and our teaming agreement more broadly, allows our companies to use our complementary areas of expertise for this award and new opportunities to come.”

Abi Clayton, Director of Future Programmes for Rolls-Royce, said, “We are delighted to win the award for the second phase of the International Bilateral Fund and to be continuing our collaboration with the UK Space Agency and our international partner BWXT. This funding will help us move towards identifying the optimum balance of technologies for our microreactor solution that will offer a broad range of space mission flexibility.”

Professor Anu Ojha, Director of Championing Space at the UK Space Agency, said: “Our International Bilateral Fund bolsters international collaboration that harnesses the UK’s national expertise, supports new space capabilities and catalyses investment. This exciting research by Rolls-Royce to develop space nuclear power is an opportunity to showcase the UK as a spacefaring nation. Innovative technologies such as this one could pave the way for continuous human presence on the Moon, whilst enhancing the wider UK space sector, creating jobs and generating further investment.”

Leicester University said the funding will make it possible to establish and develop partnerships with organisations internationally. The Space Nuclear Power group at the University of Leicester have been developing radioisotope power systems for over a decade. These power systems use the heat generated from the decay of radioisotopes, and can be used to provide heat to spacecraft or converted to electricity to power key subsystems. The technology development has been funded by the European Space Agency (ESA) European Devices Using Radioisotope Energy (ENDURE) program, supported by the UKSPace Agency.

The key difference between the radioisotope power system technology being developed in Leicester and similar products around the world is that it uses americium fuel instead of plutonium. The americium fuel gives the power systems different properties. For example, americium-241 has a half-life of more than 400 years, which means it can provide stable power outputs to spacecraft for many decades. The Radioisotope Thermoelectric Generators (RTGs) that use americium perform better in cold environments which makes them suitable for missions targeting icy moons or shadowed regions of planetary surfaces.

The £783,000 from the IBF will be used to advance mission concepts and use-cases to demonstrate the breadth of the technology applications. Working with collaborating institutes and entities in the US, Japan, and Europe, the team aims to maximise the benefits that these technologies can provide to scientific and exploration missions.

Project lead Dr Hannah Sargeant from the University’s School of Physics and Astronomy said: “The radioisotope power technology that has been developed at the University of Leicester, in conjunction with National Nuclear Laboratory, is performing extremely well in our ongoing testing campaigns. In this project, we will be working with a number of international partners to establish mission opportunities that would only be possible with the continuous and reliable power on offer. We’re excited to receive this grant from the UK Space Agency to help us build key relationships with international partners.

She added: “The first phase of funding was used to work with our international partners to understand their power needs and mission priorities. In Phase 2, we will be conducting both laboratory and concept studies to demonstrate the feasibility of the mission concepts. It will also provide an opportunity to highlight the technology to the civil and commercial space industry and show how it could be used to meet critical power needs for priority missions.”


Image: The Rolls-Royce microreactor could provide power for a lunar base (courtesy of Rolls-Royce)