Assessing the Life-Cycle Performance of Hydrogen Production via Biofuel Reforming in Europe

Currently, hydrogen is mainly produced through steam reforming of natural gas. However, this conventional process involves environmental and energy security concerns. This has led to the development of alternative technologies for (potentially) green hydrogen production. In this work, the environmental and energy performance of biohydrogen produced in Europe via steam reforming of glycerol and bio-oil is evaluated from a life-cycle perspective, and contrasted with that of conventional hydrogen from steam methane reforming. Glycerol as a by-product from the production of rapeseed biodiesel and bio-oil from the fast pyrolysis of poplar biomass are considered. The processing plants are simulated in Aspen Plus® to provide inventory data for the life cycle assessment. The environmental impact potentials evaluated include abiotic depletion, global warming, ozone layer depletion, photochemical oxidant formation, land competition, acidification and eutrophication. Furthermore, the cumulative (total and non-renewable) energy demand is calculated, as well as the corresponding renewability scores and life-cycle energy balances and efficiencies of the biohydrogen products. In addition to quantitative evidence of the (expected) relevance of the feedstock and impact categories considered, results show that poplar-derived bio-oil could be a suitable feedstock for steam reforming, in contrast to first-generation bioglycerol.