We present a deicing simulation for a practical three-dimensional geometry inside which hot air jets impinge upon a flat inclined glass surface with a layer of ice on the outside. The main goal is to study the unsteady two-phase melting process over the inclined flat surface, and to identify the traditional control parameters such as jet impingement angles for minimization of the defrosting time for given ice and glass thicknesses. A correlation for defrosting as functions of time, heat transfer parameters and impingement angles has been found. Also, in this study, the first Joule heating defroster using transparent electrodes are proposed and numerically simulated as a viable alternative. A correlation between the electrical Joule power requirement and the defrosting time is given. It is demonstrated that substantial improvements (roughly 70% reduction) in defrosting time may be achieved using Joule heating compared to the traditional jet impingement HVAC technology. (c) 2005 Elsevier Ltd. All rights reserved.