Lebensmittel und Energiepflanzen aus biologischem Anbau - unerwünschte oder nachhaltige Möglichkeiten?

Kurzfassung

Crop production is a conversion process of sun energy into biomass. Consequently, both the cultivation area and the insolation stroking this area limit the agroenergy output of the globe. Cultivation measures support the photosynthetic conversion process. Although organic cultivation measures require less energy than mainstream agriculture, the overall efficiency remains below 1%. Nevertheless, agroenergy production is captivating with many win-win situations: environmentally neutral bio-fuels replace polluting fossil fuels, farmers get better prices for energy crops, and turnover of power industry grows due to increasing energy consumption to process biomass into fuel. As a following, the state tax income improves too. However, better prices for energy crops may trigger export of environmental pollution because higher conversion efficiency in tropical countries favours the intensification of energy crop production at the expense of food production. The overall efficiency of fuel from energy crops will never be competitive with solar techniques. E.g. solar collectors replace fossil fuels for heat production much more efficiently. Yet, high process efficiencies of technical processes to convert biomass into fuel justify the production of fuel from organic waste and residues. Thus, organic farming should not focus on energy crop production but produce high quality food environment-friendly. As a measure for sustainability of fuel production from biomass, the energy surplus of energy conversion from insolation to fuel per resident and square meter is proposed.