The main issue facing road transport is the need to replace depleting oil reserves with vehicles powered by renewable energy. A long term solution for passenger cars could be the introduction of long range battery electric vehicles (BEVs). To investigate this issue the UltraCommuter (UC) BEV was developed by HybridAuto Ltd in partnership with the University of Waikato. This paper describes the development of the UC and its performance in the 2007 World Solar Challenge.

The power equation for vehicles travelling at a constant 100km/h was used to determine the critical parameters necessary for a long range BEV. The requirements are low aerodynamic drag, low rolling resistance, lightweight, high electrical efficiency and the use of high performance batteries. The requirements were then incorporated into the UC design, without compromising to greatly the practical requirements of the car.

The UC was completed in October 2007 and participated in the Greenfleet Class of the 2007 World Solar Challenge, completing 2000km of the route from Darwin to Adelaide. The UC travelled approximately 180km on one Lithium battery pack of 13kWh, 80% discharged and driving at an average speed of 85km/h. The calculated range at that speed was 174km, showing that the model accurately predicts the UC performance. There was space available in the UC for two battery packs giving 26kWh capacity and the model predicts that the range of the UC at 100km/h and 80% discharged will be 262km. The investigation shows that long range BEVs are achievable using existing technology.