The DEGREEN project (“Dielectric elastomer generators for regenerative energies”) uses extremely ductile, wafer-thin elastomer films that function like a capacitor and use the flow energy of water as low as 0.5 m/s. If one installs such a floating, environmentally friendly solution in small rivers and streams (as has already been done at the energy cooperative Oberes Werntal ), the mechanical kinetic energy of the water is directly converted into electrical energy thanks to the Venturi effect and a cycle of stretching and slackening.
The soft film of the Fraunhofer Institute for Silicate Research ISC is charged in a stretched state by applying an electrical voltage. It then falls back to its original, slackened state. In this state, a higher electrical energy is applied, which is, so to speak, sucked out once per second via a circuit. By changing the film diameter, the pressure can be varied and the generator adapted to the flow velocities of the water. Since the solution is intended as a decentralized system of power plant swarms, it requires an already functioning smart grid.