Reverse Electrodialysis
Reverse Electrodialysis
Salinity gradient technology in which cation and anion exchange membranes are used to create a "salt battery".
Salinity gradient technologies using reverse electrodialysis (RED) generate electricity from the controlled mixing of two water bodies with different salinities. RED technology typically consists of several cation and anion exchange membranes assembled to form high and low salinity compartments. When saltwater and freshwater are fed through these membranes, the opposing transport of positively and negatively charged ions creates charged poles similar to a battery.
Photo: Logan & Elimelech 2012