Technical Analysis of the Hydrogen Energy Station Concept, Phase I and Phase II

Phase I Due to the growing interest in establishing a domestic hydrogen infrastructure, several hydrogen fueling stations already have been established around the country as demonstration units. While these stations help build familiarity with hydrogen fuel in their respective communities, hydrogen vehicles are still several years from mass production. This limited number of hydrogen vehicles translates to a limited demand for hydrogen fuel, a significant hurdle for the near-term establishment of commercially viable hydrogen fueling stations. By incorporating a fuel cell and cogeneration system with a hydrogen fueling station, the resulting energy station can compensate for low hydrogen demand by providing both hydrogen dispensing and combined heat and power (CHP) generation. The electrical power generated by the energy station can be fed back into the power grid or a nearby facility, which in turn helps offset station costs. Hydrogen production capacity not used by vehicles can be used to support building heat and power loads. In this way, an energy station can experience greater station utility while more rapidly recovering capital costs, providing an increased market potential relative to a hydrogen fueling station. At an energy station, hydrogen is generated on-site. Part of the hydrogen is used for vehicle refueling and part of the hydrogen is consumed by a fuel cell. As the fuel cell generates electricity and sends it to the power grid, excess heat is reclaimed through a cogeneration system for use in a nearby facility. Both the electrical generation and heat reclamation serve to offset the cost of purchasing the equivalent amount of energy for nearby facilities and the energy station itself. This two-phase project assessed the costs and feasibility of developing a hydrogen vehicle fueling station in conjunction with electricity and cogenerative heat generation for nearby Federal buildings. In order to determine which system configurations and operational patterns would be most viable for an energy station, TIAX developed several criteria for selecting a representative set of technology configurations. TIAX applied these criteria to all possible technology configurations to determine an optimized set for further analysis, as shown in Table ES-1. This analysis also considered potential energy station operational scenarios and their impact upon hydrogen and power production. For example, an energy station with a 50-kWe reformer could generate enough hydrogen to serve up to 12 vehicles/day (at 5 kg/fill) or generate up to 1,200 kWh/day, as shown in Figure ES-1. Buildings that would be well suited for an energy station would utilize both the thermal and electrical output of the station. Optimizing the generation and utilization of thermal energy, hydrogen, and electricity requires a detailed look at the energy transfer within the energy station and the transfer between the station and nearby facilities. TIAX selected the Baseline configuration given in Table ES-1 for an initial analysis of the energy and mass transfer expected from an operating energy station. Phase II The purpose of this technical analysis was to analyze the development of a hydrogen-dispensing infrastructure for transportation applications through the installation of a 50-75 kW stationary fuel cell-based energy station at federal building sites. The various scenarios, costs, designs and impacts of such a station were quantified for a hypothetical cost-shared program that utilizes a natural gas reformer to provide hydrogen fuel for both the stack(s) and a limited number of fuel cell powered vehicles, with the possibility of using cogeneration to support the building heat load