Space Park Leicester and Perpetual Atomics achieve historic first in radioisotope heater unit safety testing
A transformative and successful safety testing campaign for future radioisotope power systems, conducted in the framework of the European Space Agency’s ENDURE (European Devices Using Radioisotope Energy) programme, has been completed by a team at Space Park Leicester and Perpetual Atomics Ltd. This builds on the Leicester and UK leadership of Radioisotope Heater Units, Radioisotope Thermoelectric Generator and Radioisotope Stirling Generator development in Europe.
Space Park Leicester, the University of Leicester’s £100 million science and innovation park, and Perpetual Atomics are excited to announce that via this testing campaign, the deployment of americium radioisotope power leaps forward via another historical and transformative achievement.
Radioisotope power technologies are essential to address some of the most challenging science and exploration space missions. Radioisotope power and heat are seen as enabling or significantly enhancing those missions and Leicester has been at the forefront of this technology development for more than two decades.
Safety is at the forefront of radioisotope power systems development and deployment and therefore understanding the safety basis or safety envelope via testing is a key requirement.
The scientists have completed a series of high velocity impact tests on the primary containment system (also called a clad) that envelopes the americium-241 radioisotope fuel form in the UK developed radioisotope heater unit (RHU). Utilising a fully representative welded platinum alloy containment solution that has been under development in Leicester for about a decade, and a specially designed non-active fuel simulant also produced in Leicester, tens of clad subassemblies were subjected to extreme high velocity impact testing.
The tests were successfully executed at the University of Dayton Research Institute’s impact physics facility in Dayton Ohio.
The clads were subjected to flyer plate impacts moving at velocities more than 1000 m per second or about three and a half times the speed of sound. In addition, terminal velocity impacts simulating ground impact at 70 m per second (after re-entry through the atmosphere) and high velocity impacts at 110 m per second and higher onto steel plates were also included in the test campaigns. The success of the testing was a testament to the design. The clads performed exceptionally well enabling the team to determine a key part of the safety basis of the system.
Initiated in 2022 by the European Space Agency, ENDURE is dedicated to establishing an independent European capability in manufacturing and launching radioisotope power systems.
A spinout from the University of Leicester, Perpetual Atomics leverages over 20 years of expertise in space nuclear power systems, space science, and space exploration. The company provides innovative solutions to space mission power challenges, ensuring sustainability and reliability across different mission scenarios, the capabilities to "survive the night” and operate in challenging environments.
Matthew Cook, Head of Space Exploration at the UK Space Agency, said: “This breakthrough by Space Park Leicester and Perpetual Atomics demonstrates exactly the kind of world-leading innovation that positions the UK at the forefront of space technology. Radioisotope power systems will be essential for ambitious deep space missions and extreme environments like the Lunar South Pole, and this successful safety testing campaign is a critical step forward. It’s an excellent example of how UK expertise, nurtured through long-term research and university-industry collaboration, delivers the transformative technologies needed for future space exploration.”
William Wells, Chief Executive Officer of Space Park Leicester, said: “Perpetual Atomics is going from strength to strength, aiming at a truly transformative impact on humanity’s ambitions in space exploration. Born from the expertise and research in space nuclear power developed over more than 20 years at the University of Leicester, and nurtured by the collaborative environment established here at Space Park Leicester, it continues to demonstrate our vision of turning cutting-edge research into real world impact.”
Professor Richard Ambrosi, CSO, founder, and Director of Perpetual Atomics, said, “These tests outline the challenge and importance of the fundamentals of safety testing in the development of radioisotope power systems. The historical implications are significant. It is a testament to the world leading capability, know-how that characterize the small and capable team in Leicester.”
Professor Emma Bunce, Director of the Institute for Space at the University of Leicester said: “This latest success from Perpetual Atomics marks another major milestone for the team, and we’re excited to see the next steps in developing this transformative technology. As we set our sights on exploring increasingly challenging environments—whether the Ice Giants in the far reaches of our Solar System or the dark, frozen surfaces of distant moons—we will require alternative sources of heat and power like those being advanced by Professor Ambrosi’s group. Their work has the potential to expand what kinds of missions the space science community can envision and propose.”
Building on Perpetual Atomics' launch in 2024, this underscores the company's commitment to integrating technology, strategic partnerships, and innovation at the core of its operations with a focus on real outcomes and real technical solutions.
Dr Alessandra Barco, Senior Research Associate at the University of Leicester and Director of Systems, Launch Safety & Regulation at Perpetual Atomics, commented, “We are very excited about this development as it underscores the unparalleled global leadership of Perpetual Atomics in radioisotope power technologies across the whole vertical including launch safety testing.”