Enabling fuel cells for standby power - chemical hydride fueling technology

Early market entry versions of PEM fuel cells and their attendant fueling systems are now being deployed with early adopters to evaluate system performance, suitability, and reliability for backup power applications for telecom and related critical power systems. One important barrier to the widespread use of PEM fuel cells will be deployment of hydrogen fuel systems to supply the fuel cell. While there are several options in this area, as yet no commercial system can claim to provide a completely satisfactory and cost effective solution. Fueling approaches fall into two categories: storage of preproduced hydrogen or on-demand production of hydrogen. In the former category, storage in steel cylinders provided by merchant suppliers is the benchmark, incumbent technology. Alternatives such as storage of cryogenic hydrogen or storage in reversible metal hydride systems are less desirable. Options where hydrogen is produced on site and then stored are also less effective. "On-demand" production of hydrogen has the key advantage of reducing hydrogen inventories which otherwise cause siting issues because of fire codes and workplace standards. It also reduces dependence on specialized distribution channels for compressed gasses and eliminates the large, heavy packaging (cylinders) required for compressed gas distribution. While there are relatively few viable options for on-demand fuel processing, this paper makes the case that the leading option, relying on rapid, catalyzed processing of mixtures of water and reactive chemical hydrides will provide a value-added, cost-effective solution.