A linear piezoelectric actuator based solar panel cleaning system is proposed in order to make a solar panel operate at the best power generation state while the solar panel is used in dusty environment. A piezoelectric actuator linearly moving on a guide is employed to drive a wiper fixed on the actuator. At a proper pressure force between the wiper and solar panel, the actuator can drive the wiper to effectively wipe a dust layer away from the solar panel's surface. The cleaning system's energy gain, which is defined as the ratio of a solar panel's output electric energy increase caused by cleaning to the energy consumption by the piezoelectric actuator, is much higher than 1. The merits of using the piezoelectric actuator in a solar panel cleaning system is that the cleaning system has light weight and compact structure, which is a common feature of piezoelectric systems. (C) 2013 Elsevier Ltd. All rights reserved.