Semester of Graduation

Summer 2019


Master of Civil Engineering (MCE)


Civil and Environmental Engineering

Document Type



Salinity gradient (SG) energy is a renewable and clean energy resource that exists worldwide from the change in Gibbs free energy when two solutions with different salinities are mixed. More recently, concentration flow cells (CFCs) have been introduced as a new technology for SG energy recovery with the highest reported power density output to date, as a result of the utilization of both the electrode potential and Donnan potential. In this study, multiple CFCs were connected to form a consecutive number of stacks, and systematic analysis was conducted to investigate the influence of both parallel and series electrical wire connections on the overall performance. For both wire connections, an effective increase in the overall power output with an increase in stack size was observed. The power densities normalized to the membrane area were however lower (3.7 W m-2 in series and 5.8 W m-2 in parallel, for 5- stacks) than the individual cell unit (8.9 W m-2) because of the cumulative mixing towards the back of the stack. Additionally, as a result of an ionic cross-conduction causing a parasitic current in the series cell, the parallel wire configuration was demonstrated to be more successful in the CFC stack than the series.

Committee Chair

Zhu, Xiuping