This chapter focuses on vibration energy harvesting using electrostatic converters. It synthesizes the various works carried out on electrostatic devices, from concepts, models and up to prototypes, and covers both standard (electret-free) and electret-based electrostatic vibration energy harvesters (VEH).After introducing the general concept of Vibration Energy Harvesting and the global advantages and drawbacks of electrostatic devices to convert mechanical power into electricity ( §1), we present in details the conversion principles of electret-free and electret-based electrostatic converters and equations that rule them in §2. An overview of electrostatic VEH, comparing the results from several laboratories (powers, sizes, concepts…) is provided in §3. In §4, we introduce several power management circuits dedicated to electrostatic VEH. These circuits are extremely important as they are the only way to turn VEH output powers into viable supply sources for electronic devices (sensors, microcontrollers, RF chips…). Assessments, limits and perspectives of electrostatic VEH are then presented in §5.

Integration of structures and functions has permitted to reduce electric consumptions of sensors, actuators and electronic devices. Therefore, it is now possible to imagine low-consumption devices able to harvest energy in their surrounding environment. One way to proceed is to develop converters able to turn mechanical energy, such as vibrations, into electricity: this paper focuses on electrostatic converters using electrets. We develop an accurate analytical model of a simple but efficient cantilever-based electret energy harvester. Therefore, we prove that with vibrations of 0.1g (~1m/s²), it is theoretically possible to harvest up to 30µW per gram of mobile mass. This power corresponds to the maximum output power of a resonant energy harvester according to the model of William and Yates. Simulations results are validated by experimental measurements, raising at the same time the large impact of parasitic capacitances on the output power. Therefore, we 'only' managed to harvest 10µW per gram of mobile mass, but according to our factor of merit, this puts us in the best results of the state of the art.