Salinity Gradient Power: An overview of applications and experiences

A huge potential to obtain clean energy exists from mixing water streams with different salt concentrations. Salinity gradient power (SGP) is based on the chemical potential difference between concentrated and dilute salt solutions. In This paper we discus about typical applications and experiences for pressure retarded osmosis (PRO) systems that is a kind of SGP systems, summarizing the current state of PRO technology at the pilot and industrial scale, and discussing future perspectives for salinity gradient energy from PRO. The first PRO configuration explored has been river-to -sea water and although this configuration has the potential to be a reliable source of base-load renewable energy, the low-energy density associated with this salinity gradient makes commercialization of PRO in this configuration unlikely. Additional PRO configurations include reverse osmosis (RO)–PRO. The higher salinity gradient available for power production in RO–PRO systems is likely to make them a more promising component of an alternative energy portfolio

Keywords:

Pressure Retarded Osmosis (PRO) , Salinity Gradient Power (SGP) , Membrane.