As the climate in Antarctica is still as inhospitable as ever, the German Aerospace Center (DLR) chose that region to set up the EDEN-ISS greenhouse there in 2018. There, food production of the future is being researched in the immediate vicinity of the German Antarctic Neumayer III Station. In the meantime, the winter crew from the Alfred Wegener Institute (AWI), including DLR researcher Dr Paul Zabel, has spent a year surrounded by constant ice. The team presented the results on 23 August: There was an unexpectedly rich harvest.
Zabel: “In just nine and a half months, we produced a total of 268 kilograms of food on just 12.5 square meters, including 67 kilograms of cucumbers, 117 kilograms of lettuce and 50 kilograms of tomatoes.”
Before his trip, by the way, Zabel had been smart enough to look into artificial vegetable cultivation in Dutch greenhouses. Zabel adds: “The taste of the fresh vegetables and their smell left a lasting impression on the winter crew and had a visibly positive effect on the team’s mood throughout the long period of isolation.”
Energy consumption lower than expected
Additionally, the scientists were surprised that they needed much less energy than they had initially expected. The average power consumption during the analog Antarctic mission was 0.8 kilowatts per square meter of cultivated area. It was consequently less than half as much as previously assumed for aerospace greenhouses, which were estimated at 2.1 kilowatts per square meter.
“This is an important aspect for a subsequent space venture and gives us confidence about the future of this idea”, said Project Manager Dr. Daniel Schubert from the DLR Institute of Space Systems. Aside from that, he stresses the potential and useful addition to space food that can be supplied by the earth.
New EDEN-ISS designed for the Falcon 9 rocket
Based on the results and experiences of the EDEN-ISS project, a new design concept for a space greenhouse has now been developed. This greenhouse is fairly compact in its design so that it can be launched aboard a Falcon 9 rocket. At the same time, it is expandable and large enough to provide sufficient food for the astronauts on the moon or on Mars. “The area used for cultivation is around 30 square meters, almost three times the size of the Antarctic greenhouse container. Using this system, around 90 kilograms of fresh food could be grown per month, which corresponds to half a kilogram of fresh vegetables per day and per astronaut if six astronauts are present,” Schubert explains.
The concept may also be combined with a biofilter system (C.R.O.P.). Its purpose is to produce a fertilizer solution for plant cultivation that is able to be utilized from biowaste and urine directly. This makes the greenhouse concept almost a fully bio-regenerative life support system for future habitats.