CAPMIX - Deploying Capacitors for Salt Gradient Power Extraction

The process of mixing sea and river water can be utilised as a power source. At present, three groups of technology are established for doing so; i) mechanical; Pressure Retarded Osmosis PRO, ii) electrochemical reactions; Reverse ElectroDialysis (RED) and Nano Battery Electrodes (NBE) and iii) ultra capacitors; Capacitive Double Layer Expansion (CDLE) and Capacitors charge by the Donnan Potentials (CDP). The chemical potential for salt gradient power systems is only limited by the feed solution concentrations and is the same for all types of salt power branches, but the electric work to the grid, however, relies on the route of conversion and means chosen therein. The CAPMIX project is a joint project to develop and explore ultra capacitors for doing so. Ultra-capacitor materials can interact with sea and river water in order to be deployed as an electricity source. The author consortium is currently exploring two routes to extract the potential free energy from mixing sea and river water by such means. These two routes are the Capacitive Double Layer Expansion (CDLE) and Capacitors charge by the Donnan Potentials (CDP), which are both recently reported, since 2009. The denominator of the two processes is the porous carbon capacitors constituting the capacitors where the chemical energy is converted into electric energy (current). The CDP differs from the CDLE mainly because it includes the use of membranes in addition to the capacitor materials. (C) 2012 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of the Centre for Renewable Energy.