Limitations of testing standards for battery electric vehicles: accessories, energy usage, and range

Issues with hydrocarbon fuel supply security, price volatility, alongside environmental, and health concerns of conventional internal combustion engine (ICE) transport technologies have raised interest in electric vehicle (EV) alternatives. However, the methods of EV testing for performance and range are inadequate adaptations from ICE testing standards designed to measure liquid fuel economy and emissions under largely unrealistic conditions. This research assesses the performance of a battery EV (BEV) by conducting a number of real-world driving tests under varying conditions including the impact of vehicle accessory usage (lights, air-conditioning, stereo, heater etc.) and additional passengers. The authors’ results demonstrate that large increases of energy consumption from accessory usage and additional passengers do occur in BEVs, which remain outside of most published EV/BEV and ICE vehicle standard test results, which themselves have recently come under scrutiny for other reasons. Owing to the relatively small battery in modern BEVs, this additional loss in efficiency and range under real-world on-road conditions may severely compromise the nascent BEV industry; particularly in areas with limited charging infrastructure.