Conceptual design and modeling of a fuel cell scooter for urban Asia

Abstract

Air pollution is of serious concern in many Asian countries, especially in densely populated cities with many highly polluting two-stroke engine vehicles like scooters. Four-stroke engines and electric battery-powered scooters are often proposed as alternatives, but a fuel cell scooter would be superior by offering both zero tailpipe emissions and combustion-scooter class range (200 km) without lengthy battery recharging times. This advanced scooter concept is explored here. A conceptual polymer electrolyte membrane fuel cell scooter design with compact metal hydride hydrogen storage is presented here; technology projections are for the short term, less than 5 years. A computer simulation is developed to examine overall vehicle design. Vehicle characteristics, fuel cell polarization curves, and a Taiwanese urban driving cycle are specified as inputs. Transient power requirements reach 5.9 kW due to rapid acceleration, suggesting a large fuel cell. However, average power is only 600 W: a hybrid vehicle with a smaller fuel cell and peaking batteries could also handle the load. Fuel economies are greater than 500 mpge at steady-state driving. Results show that hybrid vehicles do not significantly improve mileage, but would drastically reduce the size of fuel cell needed. System size is approximately the same as present electric scooters, at 43 l and 61 kg for the fuel cell, hydrogen storage, and electric motor/controller, for a total scooter weight of about 130 kg.