On the 1st of March 2015 the project “Space exploration – Life support” was brought into being. 13 organizations participated, with Daniel Schubert of the German Aerospace Center (DLR, Deutsches Zentrum für Luft- und Raumfahrt) as the team leader. Three years later, in December 2017, a ten-person crew moved to the Neumayer III Antarctic research station (operated by the Alfred-Wegener –Institute, AWI) to grow vegetables, salads and herbs in the EDEN ISS greenhouse.
Naturally, these plants weren’t grown outside in the harsh environment of the Antarctic (with an average temperature of -40 °C), but instead entirely indoors (window-less) in a hydroponic (soil-less) system. Artificial light was supplied by modern LED lamps, while nutrients and water was provided to the free hanging roots.
Can this really work? Can we really grow crops in the Antarctic? The project already finished in January 2019, so come and see yourself: The total yield after one year of growth was: 77 kg salad, 67 kg of cucumbers and 46 kg of tomatoes. Next to these crops, radishes, bellpeppers and kohlrabi was grown and harvested. They even tried to cultivate strawberries, but unfortunately without success. Why? Apparently artificial pollination appeared to be the main cause for the lack of fruits.
The greenhouse
The greenhouse, growth room or “mobile container-sized greenhouse test facility” provided 13 m² space for vegetables, salads and herbs as a (semi-) closed system. Crops were stacked on top of each other on several shelves, therefore you could even speak of ‘vertical farming’. The EDEN ISS was designed by the DLR to provide a realistic interface similar to the ISS. Why? Skip ahead to “The idea behind this project”. The greenhouse provided a constant temperature (21°C) and humidity (65%), while light was provided by high performance LED lamps. 40 different experiments ran in parallel in this container greenhouse. Paul Zabel, a DLR engineer, took care of the plants daily. The greenhouse was completely monitored and controlled by the central control station in Bremen (Germany) in case of Paul Zabel's absence, which occurred very rarely.
If you are curious, you can even follow up the growth of the crops live:
But be aware, that you won't see any plants if there are no experiments running!
What was the idea behind this project?
One of the main problems in manned long-term space travels to, for example, Mars is food supply for the astronauts. The idea behind this project is to gain new knowledge on how to overcome the problem of food provision, oxygen supply, carbon dioxide recycling on long missions towards the Moon or Mars. Plants can overcome all these needs: They provide food, oxygen, reduce carbon dioxide, recycle water and waste. Additionally, they are able to improve the mental health of the astronauts by giving them a small piece of home, memories and life. To use the words of the project:
“The overall goal of EDEN ISS is the adaptation, integration and demonstration of higher plant cultivation technologies and operation procedures for safe food production on-board ISS and for future human exploration missions (EDEN ISS Executive)”.
However, the project did not solely focus on the cultivation of crops in this innovative system. In fact, one of the main challenges was to solve occurring technological problems in the greenhouse not only fast, but also mere with the available tools at the station. This is especially important for applications on the Moon or Mars, where a stable working greenhouse with technology you can trust, or that you can easily repair, is the key of survival according to Daniel Schubert. Next to that, further key objectives were the adaptation, integration, fine-tuning and demonstration of key technologies as e.g. the LED lighting system. Then, the development and demonstration of operational techniques and processes for crop cultivation to achieve safe and high quality food. This included innovative packaging technologies for long term storage and preservation. Moreover, one part of the project focused on studying microbial behavior and dynamics in the growth room and of course appropriate countervailing measures.
Why would this be important? The constant temperature and the relatively high humidity (65 %) is basically inviting all kinds of microorganisms (bacteria or fungi), that hold the potential to negatively affect human or plant health. Food could be spoiled, water and air could be polluted. A last and very interesting objective was advancing knowledge on possible applications on our earth. Everything learned in this project could be used for our current crop farming system. Many greenhouses are already using LED lamps to improve total crop yield and fruit/vegetable quality. Several companies are researching indoor plant growth and vertical farming.
Providing the growing population with food is one of the central challenges of our generation. The earth's population is growing, while the agricultural space is shrinking and by far not enough for nearly 10 billion people in 2050 (statista.com). Aside from that, we will most probably be battling the consequences of climate change in the near future. Researchers are constantly trying to find new ways to provide food and to grow crops with regard to our changing future. Closed (windowless) growth rooms with artificial lighting could enable us to grow crops in any environmental condition year-round. The EDEN ISS project offers the possibility to monitor crop cultivation in an extreme environment as a long-term project. Everything learned from this project does not only bring us one step further in growing plants in space or on Mars, but it also contributes to our future of crop cultivation. All knowledge obtained can help us answer the question on how we can provide high quality and safe food while being energy friendly and optimizing waste management and resource usage.
Future tests will be done onboard the ISS and in a future exploration greenhouse for “planetary habitats”.
I’ll keep you updated on how this project will evolve in the future!
__________________________________________________________________________________
(Picture) Source and further reading: https://www.dlr.de/; https://eden-iss.net/
Comments