Abstract
Many public transit agencies are exploring ways in which alternative fuels can be utilized to reduce our nation’s dependency on imported oil and to avoid the environmental impacts associated with the combustion of petroleum products. Of all the alternative fuel options, electricity is among the most desirable in terms of affordability, availability, security, and sustainability. Unfortunately, limitations in battery technology result in electric vehicle operating ranges that are much lower than those of internal combustion-powered vehicles. Although opportunity charging is one strategy for increasing the driving range of electric buses by means of a series of brief recharges during normally scheduled midday layovers, it has yet to be embraced by the transit industry, in part because of the difficulties involved in having drivers connect and disconnect the bus from the charger at regular intervals throughout the day. Roadway-mounted inductively-coupled power transfer systems effectively remove this constraint by automating the charge process, thereby obviating the need for driver intervention. Ultracapacitor energy storage systems offer advantages over battery systems for such applications.