Salinity gradient power is a kind of chemical potential energy which exists between sea water and fresh water or water with different salt concentrations. Reverse electrodialysis (RED) is a process that transfers the salinity gradient to energy. Compared with other process

RED shows higher energy density. However

the studies on RED are limited to small membrane stacks. Experiments with a larger setup show that power density decreases significantly. Moreover

there is little research on the energy efficiency analysis of the RED process. In this paper

the energy transfer process of RED was simulated mathematically and the structure of the membrane stack was optimized. The power density and energy efficiency of RED at different structural parameters were also analyzed. Decreasing the thickness of the compartment could enhance both power density and energy efficiency greatly. Increasing flow length could result in higher energy efficiency

but average power density would decrease.