Electric buses are one of the solutions for improving air quality in our cities. Many states are adopting 'no new diesel bus' policies, thus increasing the pressure to develop alternative vehicles. The fledgling electric vehicle technology suffers from acceptance problems by major transit authorities due primarily to limited travel range from each battery charge. Utilizing electric buses in the Northeast has the added problem of maintaining an adequate cabin temperature without the availability of heat from a diesel motor. Heating the passenger cabin with an electric heater which draws from the batteries' stored energy significantly reduces the already modest range of these vehicles; therefore, energy conservation measures play an important role in allowing electric vehicles to provide practical transit services. IR thermography, in conjunction with air leakage pressurization diagnostics, has proven to be an excellent tool for developing energy-efficient bus designs as well as a valuable in-service performance testing method. This paper is based on tests performed on several Advanced Vehicle Systems, Inc. electric buses during research performed under Northeast Alternative Vehicle Consortium and Defense Advanced Research Projects Agency grants. The work demonstrates the thermographic methods used and the real- world increased performance of retrofitted and newly designed buses resulting from this initial Portland Transit retrofit project and in a follow-up project to develop a cold weather specification for a new generation of electric buses. Early diagnostic and new-technology follow-up thermographic performance testing was paralleled by energy modeling of early baseline and re-designed vehicles. Modeling and performance data are included. As a result of this research, thermography, air-leakage/pressurization testing, and fog analysis techniques are now being used regularly in research and development and quality assurance procedures by electric bus manufacturers.
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