The disclosure generally relates to methods, system and apparatus to wirelessly charge a mobile device using one of conventional or alternative power sources. In an exemplary embodiment, the disclosure provides a method and apparatus to detect power source as a function of its power profile linearity. Once determination is made as to whether the incoming power is harvested from natural resources or is provided from conventional AC/DC adapter/DC source, the incoming power is conditioned and impedance-matched to wirelessly energize an external load. The external load may be a device configured for wireless charging.