Low cost wave energy converter

Engineers at SouthamptonUniversityare to carrying out laboratory experiments on a device that could produce affordable electricity from the power of sea waves.

The Anaconda, which resembles a giant rubber tube, was invented and developed by Checkmate SeaEnergy, who will be collaborating in the EPSRC-funded project.

As Anaconda is made of rubber it is much lighter than other wave energy devices, dispensing with the need for hydraulic rams, hinges and articulated joints. The devices simple design means it is cheap to manufacture and maintain, enabling it to produce clean electricity at a lower cost than other types of wave energy converter.

The Anaconda is filled with water and anchored just below the sea’s surface. One end faces oncoming waves when a wave hits it the end squeezes, causing a ‘bulge wave’ to form inside the tube, which then turns a turbine fitted at the far end of the device, producing power that is fed to shore via a cable.

Researchers will use tubes with diameters of 0.25m and 0.5m to perform the experiments that will assess the Anaconda’s behaviour in regular, irregular and extreme waves. Parameters measured will include internal pressures, changes in tube shape and the forces that mooring cables would be subjected to. The data will form the basis of a mathematical model that can estimate exactly how much power a full-scale Anaconda would produce.

Initial assessments indicate that the Anaconda would be rated at a power output of 1MW and might be able to generate power at a cost of 6p per kWh or less.

Leading researcher Prof John Chaplin said: ‘A one-third scale model of the Anaconda could be built next year for sea testing and we could see the first full-size device deployed off the UK coast in around five years time.’