Bioethanol production from short rotation S. schwerinii E. Wolf is carbon neutral with utilization of waste-based organic fertilizer and process carbon dioxide capture

The sustainability of transportation biofuel production value chains is under discussion as a consequence of the implementation of the European Union Bioeconomy Strategy and renewable energy production. Greenhouse gas emissions from the biomass produced for biofuel, and the energy required during the production process are, in many cases, greater than the emission reductions from the biofuels that are produced and used to replace fossil fuels. In this study, the sustainability of bioethanol production from short rotation coppice Salix schwerinii was considered from cultivation and harvesting to biofuel production and distribution. The sustainability of the full value chain was evaluated according to the European Union Renewable Energy Directive and calculations of greenhouse gas emission savings (%) from biofuel production were compared to a reference fossil fuel (gasoline). For comparison, four bioethanol production scenarios were developed, and specific attention was focused on the utilization of waste-based organic fertilizers (for biomass production) and on carbon dioxide capture at the fermentation stage, and their effects on value chain greenhouse gas emissions. Based on our evaluation, Salix bioethanol production achieved 60% emission savings compared to the fossil reference (requirement for installations that will commence operations until end of December 2020). When waste based organic fertilizers were used in the Salix biomass production, 65% emission savings were achieved (requirement for the installations that will commence operations from 2021). Moreover, the value chain sustainability and greenhouse gas emissions balance were improved by the carbon dioxide captured during the bioethanol fermentation stage. •Salix biomass could serve as optional feedstock for transportation biofuels.•Organic waste-based fertilizers could replace chemical ones in Salix production.•Waste-based organic fertilizers considerably decreased GHG emissions from EtOH process.•Fermentation CO2 capture and utilization further improved the GHG balance.