Method for measuring energy generation and efficiency of dielectric elastomer generators

Dielectric elastomer generators convert mechanical into electrical energy at high energy density, showing promise for large and small scale energy harvesting. We present an experiment to monitor electrical and mechanical energy flows separately and show the cycle of energy conversion in work-conjugate planes. A specific electrical energy generated per cycle of 102 mJ=g, at a specific average power of 17 mW=g, is demonstrated with an acrylic elastomer in a showcase generation cycle. The measured mechanical to electrical energy conversion efficiency is 7:5%. The experiment may be used to assess the aptitude of specifically designed elastomers for energy harvesting.