Dielectric Elastomers for Direct Wind-to-Electricity Power Generation

Abstract

We present a universal dielectric elastomer energy generator that can be scaled to match the requirements of the energy source. The design couples mechanical energy directly into an out of plane deflection that deforms the film. Cycling the generator between high and low strain states while applying a bias electric field switches the device between high and low energy states; charge that is injected at low energy can then be extracted at a higher potential. We present an analysis of the energy generation capacity and mechanical stability of the device and demonstrate its scalability via a compact, low energy/low deflection device and a larger, higher energy device. We demonstrate the capability of generating approximately 40 mJ per cycle in a single layer device with an active elastomer volume of only 0.57 cm3 and a maximum observed energy conversion efficiency of over 55%. We use recently developed advances in dielectric elastomer technology including interpenetrating polymer network films and carbon nanotube electrodes to improve operational reliability and present comparative results that demonstrate an increase in lifetime by several orders of magnitude over prestrained VHB acrylic films with carbon grease electrodes.