Life Cycle Assessment and Key Parameter Comparison of Hydrogen Fuel Cell Vehicles Power Systems

Abstract

Hydrogen fuel cell vehicles (HFCVs) are regarded as potential solutions to the problems of energy security and environmental pollution. To explore the energy consumption and pollutant emissions of fuel cell vehicle power systems, data inventories of an HFCV power system were established, and quantitative evaluation calculations and prediction analysis were carried out for fuel life cycle energy consumption and greenhouse gas emissions of Chinese fuel cell vehicles in 2030 based on the technology roadmap for new energy vehicles by modeling with GaBi software. The effects of different types of bipolar plates, different energy control strategies, and different hydrogen production methods on the environment were studied, with uncertainty analysis as the key parameter. The results showed that fossil energy consumption (ADPf), global warming potential (GWP, CO2 equivalent), and acidification potential (AP, SO2 equivalent) for the HFCV power system in the fuel life cycle were 1.35×105 MJ, 9108 kg, and 15.79 kg, respectively. The energy consumption and greenhouse gas emissions in the production of the power system were higher than those in the use stage, mainly because of the fuel cell stack and hydrogen storage tank. In the manufacturing process of metal bipolar plates, graphite composite bipolar plates, and graphite bipolar plates, graphite composite bipolar plates had the most comprehensive environmental benefits. Optimizing the energy control strategy will reduce hydrogen energy consumption. When the hydrogen energy consumption was reduced by 22.8%, the life cycle energy consumption and greenhouse gas emissions of the power system were reduced by 10.4% and 8.3%, respectively. For life cycle power systems, the use of hydrogen from electrolysis operated with water power reduced the GWP by approximately 39.6% relative to steam methane reforming. In contrast, the application of hydrogen from electrolysis operated with the Chinese electricity grid mix resulted in an increase in GWP of almost 53.7%. Measures to reduce fossil energy consumption and global warming potential in the life cycle of fuel cell vehicle powertrains include optimizing energy control strategies to reduce hydrogen energy consumption, scaling up the hydrogen production industry using water electrolysis for renewable energy power generation, and focusing on key technologies of fuel cell stacks to improve performance.