Comparative life cycle assessment of eight alternatives for hydrogen production from renewable and fossil feedstock

The objective of this study is to conduct a comparative life cycle assessment of eight hydrogen production scenarios. The analysis enables a comparison of the sustainability performance of H-2 production alternatives, as well as the identification of the key elements of each option. The scenarios investigated are based on (1) fossil CH4 reforming processes, namely steam reforming, partial oxidation and auto-thermal reforming; (2) biological CH4 reforming, i.e., steam CH4 reforming, partial oxidation and auto-thermal reforming; and (3) bioethanol-to-hydrogen systems, namely steam reforming and auto-thermal reforming. The assessment is carried out with the SimaPro 7.1 program. Both CML baseline 2000 and Eco-indicator 99 are used as life cycle impact assessment methods. The results indicate that the biomethane reforming systems have the lowest impact of all of the systems. The fossil CH4 reforming scenarios produce the highest emissions of global warming gas and have the greatest contribution to the abiotic depletion potential impact. Although wheat-derived bioethanol is considered to be a biofuel, bioethanol-to-hydrogen production systems have a higher impact than fossil CH4 on acidification, eutrophication, ozone layer depletion and toxicological impacts. This research provides regulators and policy makers with a basis upon which to guide further research and development in the H-2 sector. (C) 2012 Elsevier Ltd. All rights reserved.