Engineer develops underwater turbine to generate coastal electricity

Engineer David Mummery has built an underwater turbine that generates electricity from tidal currents. The device, called the Swimmer Turbine, sits on the sea floor and stays completely hidden below the surface. It produces 50 kilowatts of power, which is enough to supply around 30 homes.

Mummery tested an early version in a fast-flowing Highland river in the early 2010s, at a location he kept secret. Earlier designs were attached to boats, but the current model is fixed to the sea floor near the shore.

The company behind the project, Flex Marine Power, received nearly £968,000 from the UK government to build a commercial version. The money supported a team of nine people working on the turbine.