Isabel Rubner^1,, Linda Baur², Bettina Grau², Jörg Steinbrenner³, Benedikt Hülsemann³

In school and university education, it is important to integrate current and innovative topics into the curricula. Curricular innovation research follows this line of research. Especially in the field of education for sustainable development, there is a great need to didactically prepare the topics on the basis of the Sustainable Development Goals and to convey them to pupils and students at an early stage. Energy supply is currently a highly complex and central topic from a climatic and political point of view. In this context, biogas production as a renewable energy source has become even more important. For example, more than 9000 biogas plants are currently in operation in Germany. The principle of biogas production has long been implemented in school experiments. However, it was recognized that the methods used in school experiments usually do not produce methane. Therefore, a new experimental setup was developed to ensure methane production in these experiments and to demonstrate biogas practically. Dried sugar beet was used as a substrate for biogas production. It was mixed with compost or garden soil, which contained the microorganisms required for biogas and methane production and served as inoculum. An inexpensive gas chromatograph was used to measure the methane concentration in the biogas produced. In a first attempt, to ensure methane production, sodium carbonate was added as a buffer to keep the pH of the fermentation broth in the optimal range (pH 7-8). To avoid the addition of buffer, the optimal ratio of compost to sugar beet was then investigated in collaboration with the University of Hohenheim. Based on these results, methane formation was observed after 8 days and methane concentrations of up to 65 vol% were measured. Overall, this trial was a practical way to demonstrate the anaerobic digestion process to students by production of biogas. This study also highlighted the great benefits of interdisciplinary collaboration in curriculum innovation research.

Hohenheim Biogas Yield Test, Anaerobic Digestion, Methane, Biogas, School, Education, Curricular Innovation Research