Analysis of a hydro-osmotic power plant using a simple mathematical model

Osmotic energy created by salinity gradient is a novel energy source. The chemical potential difference of two liquids with dissimilar salinities can be used to generate a flow of water across a semi-permeable membrane. The Pressure-Retarded Osmosis (PRO) concept controls the flow of the water across the membrane and contributes to the production of electrical energy with a hydraulic turbine. This study describes a simple mathematical model for evaluating the effectiveness of application of the PRO process in a hydro-osmotic power plant. The influences of pressures and salt concentrations of the inlet streams as well as the concentration polarization across the membrane on the membrane power density and plant efficiency were investigated. The effects of liquid temperature and membrane characteristics (water and salt permeability) on power plant performance were also studied.