Greenhouse Modules and Regenerative Life-Support Systems for Space

Abstract

Long exploration missions to the Moon and Mars will require the growth of food on site to sustain the crew because current launchers are unable to send the required mass of consumables into orbit at an affordable cost. Growing fresh food will also be of prime importance for the crew dietary and psychological requirements. ESA expertise on advanced life support systems within the MELiSSA (Micro-Ecological Life Support System Alternative) project, coupled to the EDEN (Evolution and Design of Environmentally-closed Nutrition Sources) project in DLR join forces to study a greenhouse within the MELiSSA loop for a manned base on the Moon surface. Both projects are aimed at studying and developing regenerative life support systems for long duration space missions: MELiSSA is a closed artificial ecosystem program based on microbiological and physicochemical waste degradation and higher plants; EDEN combines different CEA Technologies (Controlled Environmental Agriculture) within an automatic planetary Greenhouse-Module (GHM). Previous studies on Greenhouse Modules have addressed mass, volume, and energy consumption needs but the technologies and data on which these calculations were based are now outdated or were limited at that time. They thus need to be reassessed to have better estimates of these variables and evaluate what it takes to grow plants on the Moon. A study of the lunar environment based on various elements such as illumination, radiation levels, accessibility, and temperature gradients, enables to make a comparative analysis for the best location to setup a greenhouse module on the Moon surface. Trade-offs between electrical and natural lighting, and various grow accommodation options, based on the ALISSE criteria are also conducted. Finally, this leads to the identification of critical points and recommendation on future work for preliminary greenhouse concepts.