Osmotic power

EPFL researchers have devised a system that generates electricity from osmosis. It consists of a salt water containing compartment separated from another containing fresh water by a thin membrane of molybdenum disulphide. The membrane has a hole, or nanopore, through which ions pass into the fresh water until the two fluids’ salt concentrations are equal. As the ions pass through the nanopore, their electrons are transferred to an electrode generating a current. According to their calculations, a one metre square membrane with 30% of its surface covered by nanopores should be able to produce 1MW of electricity.