A swell time

While pleasure boats are on the move, they can power their lighting, fridge and hi-fis from a generator run by the engine. When the boat is moored, the electrics have to rely on batteries, and to keep them charged up Raymond Gotto of Watford, Hertfordshire, suggests harvesting energy from the sea (GB 2365929). The sea’s swell continually moves a boat to and fro at its mooring. Gotto’s boat is tethered to the dock by a long belt wound round a spring-loaded reel that is connected to the shaft of an electric generator. Each time the boat moves gently away from…