Ocean Wave-Powered Desalination Duck.

Stephen Salter at Edinburgh University, UK, designed a "desalination duck" device that uses the ocean waves to power a desalination pump:

Stephen Salter at Edinburgh University, UK, first designed a device to generate electricity from wave power in the 1970s. It was dubbed the ‘Edinburgh Duck’ because buoyant cylinders on one side resembled a beak, while the other, tethered end bobbed up and down as it rode the waves.

Salter and colleagues are now working on a version that purifies seawater by driving a pump with its rocking motion. This would avoid the high energy demands of conventional desalination plants, and could be installed in arid countries with good access to seawater, such as Australia and Israel.

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