However, problems abound, and no cost effective, practical system is in sight at this point. First, an onboard gasoline reformer would be expensive and would require an excessive amount of platinum. Second, start-up time for the reformer system would be on the order of minutes rather than seconds. Third, an integrated reformer/fuel-cell system has not yet been tested to evaluate operating dynamics. Fourth, gasoline molecules form soot in the reformer, suggesting that the hydrocarbon stream would have to be lighter than conventional gasoline and that sulfur levels would have to be very low.
In light of the infrastructure costs of hydrogen storage and the status of the onboard reforming program, the committee feels that PNGV should assess approaches for generating hydrogen at service stations by, for example, reforming natural gas or gasoline. In effect, this would replace the mobile reformer on each car with larger, stationary reformers that could provide fuel for many vehicles. The larger size of these units would provide additional design flexibility to deal with important technical issues, such as platinum requirements and the operability of the system with gasoline. In addition, with this option, hydrogen could be generated from natural gas, a preferred reformer feedstock that would minimize cost. Finally, this approach would avoid the infrastructure costs of a gaseous hydrogen distribution system and, therefore, could be implemented more quickly.
When investigating this option, PNGV should take advantage of the expertise of the National Aeronautics and Space Administration, which is developing new technology for hydrogen storage, leak detection, and firefighting. PNGV should also take advantage of the expertise of the petroleum and chemical industries, which have extensive experience in generating, storing, transporting, and using hydrogen in refineries and chemical plants.
Recommendation. Defining automotive system/fuels trade-offs and establishing the basis for planning for supplying required fuels as higher efficiency vehicles become commercially available will require extensive cooperation among automotive and petroleum industry representatives at all levels of responsibility. PNGV should expand and strengthen its cooperative efforts with the petroleum industry, including issues related to fuels for fuel cells. Government leadership will be necessary to initiate this cooperative effort and provide incentives for petroleum company involvement.
Recommendation. PNGV should undertake a study to assess the opportunities and costs for generating hydrogen for fuel cells at existing service stations and storing it on board vehicles and compare the feasibility, efficiency, and safety of this option with onboard fuel reforming. This study will help PNGV determine how much additional effort should be devoted to the development of onboard fuel reforming technologies.