Characterisation of most relevant feedstock for biogas and bioethanol production in organic farming

Summary

Bioenergy production from local bioresources has a great potential. It is important to reduce dependency on fossil fuels and decrease green house gas emission in organic agriculture (OA). Both biogas and bioethanol can be produced in OA and significantly contribute to the sustainability of organic farms. Soil fertility is the basis for OA: it has been of concern that the fertility might decline if most of the organic residues were converted into energy and only effluent from anaerobic digestion process was recycled. However, by intelligent management of organic residues and crop rotation it is possible to avoid decrease of soil fertility and at the same time produce renewable energy.
The presented study is part of the BioConcens project (http://www.bioconcens.elr.dk/uk/). This study is focused on characterisation of relevant feedstock for co-production of biogas and bioethanol within organic farming. Clover grass silage, dry clover grass and dried grass from meadows were selected. Theoretical biogas and bioethanol yields were calculated. Biogas potential batch tests were performed for each substrate individually and the obtained yield in the lab was compared to the theoretical one. It is expected that the onfarm production of the bioenergy would improve not only sustainability of such a farm but as well economics. Further investigations will be carried out.