Improving sustainability of maize to ethanol processing by plant breeding and process optimization

Efficient management of plant resources is essential for a sustainable biobased economy. The biomass conversion efficiency and sustainability performance depend greatly on the choice of feedstock and the applied processing technology. The aim of this research was to enhance the biomass use of maize stover for bioethanol production, by combining plant breeding of the maize feedstock with various pretreatment severities and applying an exploratory assessment of the environmental and economic impacts. We found that systematic genetic gains of cell wall digestibility can lead to significant advances in the total glucose productivity and also in the sustainability performance. The best maize characteristics tested led to a total glucose productivity of 3.7 ton per hectare using mild processing conditions. This matches the highest realizable yields under severe processing conditions. In the best scenarios the environmental and economic impacts of operating conditions were reduced by 15% compared to the benchmark.