Abstract

Due to high energy efficiency and zero emissions, some believe fuel cell vehicles (FCVs) could revolutionize the automobile industry by replacing internal combustion engine technology, and could be boosted and boomed in China first. However, hydrogen infrastructure is one of the major barriers. Because different H2 pathways have very different energy and emissions effects, the well-to-wheels analyses are necessary for adequately evaluating fuel/vehicle systems. The pathways used to supply H2 for FCVs must be carefully examined by their WTW energy use, GHGs emissions, total criteria pollutions emissions, and urban criteria pollutions emissions.

Ten hydrogen pathways in Shanghai have been simulated. The results include well-towheels energy use, GHGs emissions, total criteria pollutions and urban criteria pollutions.

A fuel-cycle model developed at Argonne National Laboratory – called the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model – was used to evaluate well-to-wheels energy and emissions impacts of hydrogen pathways in this study. Because GREET model has no coal and naphtha-based hydrogen pathways, four hydrogen pathways (No. 5-8) computer program were added to GREET in the research. To analyze uncertain impacts, commercial software, Crystal BallTM, is used to conduct Monte Carlo simulations. Instead of the point estimates, the results of this study were probability distributions.

Through the research, the following conclusions can be achieved:

(1) All the pathways have significant reduction in WTW petroleum use, except two H2 pathways from naphtha, which achieve about 20% reduction in WTW petroleum.

(2) All the pathways have significant reduction in WTW urban criteria pollutions emissions, except two H2 pathways from coal, which offer significant increase in WTW urban SOx emissions.

(3) The NG-based H2 pathways have best WTW energy efficiencies, and the electrolysis H2 pathways have worst WTW energy efficiencies. The WTW energy efficiencies of H2 pathways from naphtha and coal are between NG-based pathways and electrolysis pathways. The pathways from naphtha have higher energy efficiencies than the pathways from coal. Only four pathways (G NG C, G NG R, G N C, and L NG C) offer WTW energy benefits, and the other six pathways consume more WTW energy than baseline-conventional gasoline vehicles.

(4) Changes in WTW GHGs emissions have nearly identical results with changes in WTW energy use.

(5) For WTW total criteria pollutions emissions, all pathways can achieve significant reduction in WTW total VOCs and CO. the other criteria pollutions emissions-NOx, PM10, and SOx, have certainly reduction in NG and crude oil-based H2 pathways, but have significant increase in electrolysis and coal-based pathways.