Satellite

Biography

Biography: Stefan Belz

Abstract

Life Support Systems (LSS) are an essential subsystem of human spaceflight systems. An LSS allows humans to survive, to live and to work in space. Existing physicochemical technologies used on the International Space Station (ISS) enable water and oxygen generation. Far-distant and long-term exploration missions (e.g. lunar surface habitat or a manned mission to Mars) require a higher closure of the water, oxygen and carbon loop. Especially the carbon loop can only be closed by biological technologies, i.e. food production in space. Higher plants offer an in-situ resource for food. These systems are of a high biological order and require a specific environment to grow. High engineering effort is necessary to provide such an environment in space, especially under microgravity conditions and higher radiation loads. However, microalgae as single-cell organisms compared to higher plants have a higher harvest index, up to 10-fold higher growth rate, a higher light exploitation and need no soil. Microalgae enable an efficient use of photosynthesis in space (conversion of carbon dioxide into biomass and oxygen). Engineering solutions are developed to provide the optimum growth condition of a microalgae species such as temperature, pH value, dissolved carbon dioxide and oxygen concentrations. The Institute of Space Systems investigates cultivation techniques since 2010 in cooperation with the DLR. Knowledge and expertise on cultivation, feeding, harvesting, gas supply and gas extraction are now the basis for the spaceflight experiment PBR@ACLS (Photobioreactor at the Advanced Closed Loop System). The on-going results and development of breadboard testing are presented.