River water flowing into sea water can be a battery

Image credit: ACS

New entropy battery captures energy from the imbalance of salinity in fresh water and seawater.

(PhysOrg.com) -- A team of researchers, led by Dr. Yi Cui, of Stanford and Dr. Bruce Logan from Penn State University have succeeded in developing an entropy battery that pulls energy from the imbalance of salinity in fresh water and seawater. Their paper, published in Nano Letters, describes a deceptively simple process whereby an entropy battery is used to capture the energy that is naturally released when river water flows into the sea.

Up to now, this kind of process has been accomplished by passing seawater though a membrane which unfortunately is too costly to merit creating large-scale operations.
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