What are the challenges posed by climate change that your consortium's research is responding to?

Volkmar Keuter: Climate change is affecting agricultural systems worldwide. Longer periods of heat lead to lower yields. In addition, we see the influence of climate change on energy systems and the resulting CO₂ emissions. With SUSKULT, we are reacting to these changes by taking plant cultivation indoors. This indoor production can take place independently of the climate prevailing outside, sometimes with higher yields. We are also independent of fertiliser and food imports, which means that our cultivation system is resilient in the face of current challenges. In addition, CO₂ emissions are reduced through short transport routes and in production.

What is the solution your consortium is researching?

Keuter: In SUSKULT we are developing a cycle-based system for the cultivation of food at the place of need. Consumers become prosumers because they produce the nutrients for plant cultivation themselves. In our recently inaugurated pilot plant, the macronutrients nitrogen, phosphorus and potassium, which are essential for plant nutrition, are extracted from a partial stream of wastewater. This produces a liquid fertiliser for the cultivation of sustainable, fresh and healthy products such as lettuce, herbs, sweet potatoes and duckweed.

Which political factors does it depend on whether this solution works? 

Sandra Schwindenhammer:  By linking the wastewater system with the food production system, SUSKULT is building a bridge that politicians themselves have not yet fully completed. That is why we come up against regulatory limits, for example in fertiliser legislation. Since we at SUSKULT produce food hydroponically - i.e. without soil - we are currently unable to obtain organic certification, even though we meet many of the criteria of organic farming. In order to roll out innovative approaches like SUSKULT in the future, enabling regulation and incentive systems are needed, also to make such approaches economically competitive. As far as the environmental costs of agricultural systems are concerned, discussions on CO2 pricing are already happening.

Keuter: Especially with regard to climate change, the political responsibility is not only to deal with the issue, but to break down what visions like SUSKULT can mean in the overall context of agricultural systems. This requires a rethinking, both at the societal and the political level, in order to make the conversion of the agricultural economy to secondary raw materials more possible. Only in this way the corresponding transfer from science can succeed.

What needs to be done at societal level?

Schwindenhammer: In general, we see an increasing socio-political discourse about how food systems should be designed in terms of climate change. But even if many people already take sustainability aspects into account when consuming, it is ultimately also a question of costs. This leads us back to political responsibility.

How will the results of SUSKULT change people's everyday lives?

Keuter: In times of multiple crises, we have learned what dependence on global supply chains means. The climate crisis also shows us, through drought, heat or cold waves in the producing countries, that the resulting yield losses reach German consumers as significant price increases. At the end of the day, nutrient and energy cycles and local food production ensure stable prices.

Schwindenhammer: Within the short, closed-loop value chain in SUSKULT, people in the city can directly consume sustainable food. We hope for other forms of distribution and recycling. Nearby sewage treatment plants, weekly markets could emerge in the future.