ONBOARD STORAGE ALTERNATIVES FOR HYDROGEN VEHICLES

Three viable technologies for storing hydrogen fuel on cars are curren tly available: compressed gas, metal hydride adsorption, and cryogenic liquid. However, each of these has significant disadvantages: volume, weight, boiling losses, or energy to compress or liquefy the hydrogen . Two alternative approaches are analyzed in this paper: pressure vess els with cryogenic capability and a combination of a metal hydride and liquid hydrogen storage. These alternatives are compared to baseline compressed hydrogen and liquid hydrogen (LH2) storage in terms of volu me, vehicle range, dormancy, energy required for fuel processing, and cost. The results indicate that the alternative methods can result in a reduced volume, if packaging is a constraint; or in an extended rang e, if this is a desirable feature. Cryogenic pressure vessels, with on e-fifth the insulation of LH2 systems, have comparable or better dorma ncy than LH2 systems. Energy requirements and cost appear favorable fo r the alternative systems.