Modular lunar RTG · Research framework for the design and optimisation of a modular Radioisotope Thermoelectric Generator for Lunar exploration and exploitation

Lunar colonization and exploitation, being the aim of project Artemis, requires reliable energy production, which is possible by the radioisotope thermoelectric generator (RTG). RTG units contain a radioisotope heat source coupled with thermoelectric modules (TEM) which convert the produced heat into electricity. The power output of the RTG is fixed by design and it cannot dynamically change. However, the dynamic and interconnected environment of a human colony, which involves life support, scientific research, resource mining, manufacturing, and exploration activities, would benefit from a flexible and integrable RTG, which can employ active and passive cooling functionalities, participate in the systems’ heat exchange, and incorporate different radioisotopes. Beyond system flexibility, the developed RTG must be able to withstand the extreme environmental challenges imposed by the extended diurnal day-night circle of the lunar surface. The excessive solar exposure during the lunar day can overheat an exposed RTG and cause irreversible damage. To address these challenges, this project defines three distinct objectives. The first aims to establish a research framework which combines 3D multi-physics (thermal, thermoelectric and mechanical analyses) simulations to evaluate the RTG behaviour with 1D multi-parametric investigations for rapid optimisation. In the second objective, the developed tools will be used to conceptually design a flexible RTG which can be safely and reliably employed on the lunar surface. To further establish it as a key component of the lunar infrastructure, its components should be manufactured locally through an in-situ resource utilisation (ISRU) scheme. Thus, in the third objective, a metric system will be produced to identify ISRU-suitable RTG and TEM components. The produced results will be key to advance the RTG technology, inspire innovation in RTG and TEM manufacturing, and advance DLR, ESA and Europe in the field of space exploration.