Charging of a mobile device in an ad hoc parked vehicle charging system. A plurality of mobile device users and associated mobile devices are registered in an ad hoc parked vehicle charging system with a charging profile. A plurality of charging vehicles are also registered in the system with a charge supply profile. A mobile device user and associated mobile device are authenticated as a registered user in the system. A plurality of the registered charging vehicles parked within a preset distance range of the authenticated user and associated mobile device are located and one of the parked registered charging vehicles is selected based on an energy allocation criteria. A charging connection is established between the authenticated mobile device and the selected parked vehicle and charging of the mobile device is automatically controlled according to the user's charging profile, the vehicle's charge supply profile and the energy allocation criteria.