An Analysis of Start-up for an Operational Fuel Cell Transit Bus

The start-up process of an operational phosphoric acid fuel cell transit bus has been investigated. The bus employs a hybrid arrangement of a 50 kW Phosphoric Acid Fuel Cell (PAFC) engine in parallel with Nickel-Cadmium batteries on a 30-foot heavy-duty transit bus chassis manufactured by Bus Manufacturing Inc. The bus uses methanol as the primary fuel, which is processed through a steam-reformer to produce hydrogen used in the fuel cell. Start-up of the fuel cell bus is defined as the time that is required to heat up the fuel cell and sub-components to operating temperatures and to establish operating flow conditions. While in general fuel cell vehicles produce low emissions and are very efficient while operating, start-up of the fuel cell bus represents a significant time requirement, power and fuel consumption, and considerable pollutant emissions with no usable output power. A description of the start-up procedure for the bus, fuel and power usage, average time required, and analysis of emissions data are presented.