A Desiccant Dehumidifier for Electric Vehicle Heating

Abstract

Vehicle heating requires a substantial amount of energy. Electric vehicles (EVs) generate little waste heat, and using battery energy for heating may consume a substantial fraction of the energy storage capacity, reducing the vehicle range, which is one of the most important parameters in determining EV acceptability. This paper analyzes the applicability of a desiccant dehumidifier for providing comfort heating in an EV with reduced energy consumption. A dehumidifier can reduce the heating load in a vehicle because it adsorbs the water vapor generated by the passengers, thereby avoiding water condensation on the windows without requiring a high external air ventilation rate or a high window temperature. The results indicate that the desiccant dehumidifier can reduce the steady-state heating load by 60 percent or more under typical conditions. The reduction in heating load is such that waste heat may be enough to provide the required heating under most ambient conditions. Desiccant system dimensions and weight appear reasonable for packaging inside an EV.