On 2 October 2018, the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt, DLR), European Space Agency (ESA) and Air Liquide signed the 'LUNA Energy Project' cooperation agreement at the International Astronautical Congress (IAC) in Bremen. The aim of this agreement is to build an energy system for a lunar simulator. The so-called Lunar Analogue (LUNA) is expected to be developed by the end of 2019 and will be located immediately next to ESA's Astronaut Training Centre (EAC) at the DLR site in Cologne. It will be used for five years.
"LUNA will test technologies for operating a lunar base, focusing on a self-sufficient energy supply. The findings will be incorporated into future manned space exploration missions," said Hansjörg Dittus, DLR Executive Board Member for Space Research and Technology. "At DLR, the research areas of space and energy are working closely together on this project, because on Earth, the technologies may contribute to a more environmentally friendly energy supply."
Solar energy supply – the backbone of a lunar base
Research into a robust and reliable energy system is at the heart of Project LUNA. Large amounts of energy must be stored as compactly as possible – and over an extended period of time – in order to meet the high demand of a lunar base. After all, one night lasts over two weeks, or 354 hours, in most lunar regions, making it an enormous challenge for the energy system.
Six hundred tonnes of Eifel stone are being piled up over 1000 square metres. As this material has similar mechanical properties to the lunar regolith, it is ideal for simulating the surface of Earth's satellite. The dome-shaped 'Flexhab' habitat is being built and operated by ESA, along with the 'LUNA Energy Facility', a system for generating and storing energy. The main components of the energy system are the fuel cell supplied by the partner, Air Liquide, and the electrolysis unit from the DLR.
The plan is to use solar energy to split water into hydrogen and oxygen by means of polymer electrolyte membrane electrolysis. These two elements can be stored and then converted back into energy (and water) as required, using the fuel cell. DLR has many years' experience in producing hydrogen as a renewable energy source. Most recently, the large-scale, decentralised production of H2 was successfully demonstrated during the H2ORIZON Project at the DLR site in Lampoldshausen.