The PULSAR research project, led by Tractebel and funded by Euratom, unveiled the conceptual design of a plutonium-238 (Pu-238)-fuelled radioisotope power system (RPS) for lunar space missions.
As part of its mission, the PULSAR consortium aims to establish European capabilities for Pu-238-fuelled RPS technology essential for powering spacecraft in environments where solar energy is insufficient. Completed at the end of 2024, the project delivered significant outcomes, including:
The consortium includes leading organisations such as the European Commission’s Joint Research Centre (JRC), SCK CEN, CEA, INCOTEC, ArianeGroup, Airbus Defence and Space, the University of Bourgogne Franche-Comté, and ARTTIC.
Radioisotope power systems (RPS) generate energy through the decay of isotopes like Pu-238, converting heat into usable electrical power. This technology is critical for space missions operating in low-light conditions, such as those on the moon.
The PULSAR consortium’s RPS is designed to support a lunar rover or cargo carrier requiring 100–500 We. It incorporates safety measures for launch from the Guiana Space Centre and features two Stirling engines powered by a centrally located Pu-238 heat source. The modular design ensures resilience against motor failure, with an expected thermo-electrical conversion efficiency of 20%.
Tractebel nuclear experts conducted comprehensive engineering studies, including structural integrity checks, radiation dose assessments, thermal analysis, and mechanical assembly development. The team developed a 3D mechanical and thermal model to simulate lunar conditions, providing a foundation for future design iterations and higher Technical Readiness Levels (TRL). This work lays the groundwork for Europe’s participation in the upcoming Argonaut lunar lander mission.
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“What the PULSAR consortium has achieved will help position Europe as an autonomous global leader in space nuclear technologies. Tractebel leads European research projects focused on advancing nuclear technologies for space exploration, including RPS and radioisotope production, electric propulsion, and fission surface systems. By leveraging our nuclear expertise, we are pushing the boundaries of space exploration and enabling Europe to lead in this final frontier.” |
| Brieuc Spindler, Space Product Manager, Tractebel |
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