| Aspects of the hydrogen economy are addressed by quantifying impacts and costs associated with a hydrogen-based energy infrastructure. The following questions are answered: (1) Should hydrogen replace standard fuels for electricity and transportation? (2) If so, how should this hydrogen be produced? (3) Which stages of these life cycles contribute the largest impacts? Where should research efforts focus to lower the overall life cycle impacts?; Based on the external cost analysis, all hydrogen alternatives provide a reduction in annual external costs from the base cases (minimum 16% reduction for transportation, 62% for electricity generation). The Solar Thermochemical (STC) option has the lowest costs by far, with Biomass and Wind yielding very similar costs. The Steam Methane Reforming (SMR) option has the highest external costs for the hydrogen options, but is still significantly lower than the base cases.; It is recommended that hydrogen should be produced from STC and Wind Electrolysis, with the possible use of SMR to aid in the creation of a hydrogen infrastructure. Because SMR is the most developed hydrogen technology and yields a reduction in impacts over the base cases, this technology could be used as a transitional phase to create a working hydrogen infrastructure for superior processes such as STC and Wind Electrolysis. Despite high impact assessment results from SimaPro, the external costs associated with the Biomass option are shown to be comparable with those for Wind Electrolysis. (Abstract shortened by UMI.)... |
