Life cycle energy consumption and GHG emissions of biomass-to-hydrogen process in comparison with coal-to-hydrogen process

Abstract

Developing coal-to-hydrogen (CTH) process is a major way to relieve the conflict between hydrogen supply and demand. The environmental problems caused by the utilization of fossil energy have driven the progress of alternative hydrogen production processes. Biomass energy, as an attractive renewable hydrogen resource, can solve some environmental problems. In this study, CTH and biomass-to-hydrogen (BTH) processes are modeled and studied. Based on the simulation results, the life cycle analysis energy consumption (EC) and greenhouse gas (GHG) emissions of CTH and BTH processes are performed. The system life cycle boundary includes raw material production (or collection); transportation; synthesis gas generation; hydrogen purification; hydrogen transportation and application. The results show that the EC of the BTH process is 75.4% lower than the corresponding value of CTH process. GHG emissions of BTH process are 89.6% lower than corresponding values of CTH process. In addition, sensitivity analysis shows that pipeline transport is the most environmentally friendly transport mode. Gasification temperature is in the range of 1400–1500 °C, the system achieves the highest energy efficiency and the lowest GHG emissions. Suggestions were proposed for the policy formulation of the sustainable development of the hydrogen industry, which is of great significance to reduce GHG emissions and improve energy efficiency.