Sustainability study of hydrogen pathways for fuel cell vehicle applications

The present work has conducted a comprehensive life-cycle analysis of energy consumption and greenhouse gas (GHG) emission for various fuel/vehicles systems. Focus is placed on the hydrogen-based fuel cell vehicle (FCV) technology, while the gasoline vehicle (GV) equipped with an internal combustion engine (ICE) serves as a reference technology. A fuel-cycle model developed at Argonne National Laboratory, the GREET model, is employed to evaluate the well-to-wheels (WTW) energy and emissions impacts caused by various fuel/vehicle systems. Six potential hydrogen pathways using renewable and non-renewable energy sources are simulated, namely, steam reforming of natural gas and corn ethanol, water electrolysis using grid generation and solar electricity, and coal gasification with and without carbon sequestration. Results showed that the FCVs fuelled with solar electrolysis hydrogen have the greatest benefits in energy conservation and GHG emission reduction. However, by incorporating with the economic consideration, hydrogen from the natural gas reforming is likely to be the primary mode of production for the initial introduction of FCVs.