Washington, July 4 : US scientists have invented the 'Anaconda', a device consisting of a giant rubber tube, which may hold the key to producing affordable electricity from the energy in sea waves.
The developer of the rubber snake, Checkmate SeaEnergy, describe it as a totally innovative wave energy concept.
Its ultra-simple design means it would be cheap to manufacture and maintain, enabling it to produce clean electricity at lower cost than other types of wave energy converter.
The Anaconda is closed at both ends, and filled completely with water. It has been designed in such a manner that it can be anchored just below the sea's surface, with one end facing the oncoming waves.
A waves hitting the end squeezes it, and causes a 'bulge wave' to form inside the tube.
While the bulge wave runs through the tube, the sea wave that created it runs along the outside of the tube at the same speed, and thereby squeezes the tube further and causes the bulge wave to grow bigger and bigger.
A turbine fitted at the far end of the device is turned by the bulge, and the power thus produced is fed to shore through a cable.
Since the Anaconda is made of rubber, it is much lighter than other wave energy devices that are primarily made of metal, and dispenses with the need for hydraulic rams, hinges and articulated joints.
This characteristic of the device may help reduce capital and maintenance costs, as well as scope for breakdowns.
However, this concept is still at an early stage of development, and has only been proven at very small laboratory-scale thus far.
Engineers at the University of Southampton are now planning larger-scale laboratory experiments, and novel mathematical studies designed to determine the Anaconda's potential performance as part of a programme that will be funded by the Engineering and Physical Sciences Research Council (EPSRC).
Using tubes with diameters of 0.25 and 0.5 metres, the experiments 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 study will also help estimate exactly how much power a full-scale Anaconda would produce.
When built, each full-scale Anaconda device would be 200 metres long and 7 metres in diameter, and it will be deployed in water depths of between 40 and 100 metres.
"The Anaconda could make a valuable contribution to environmental protection by encouraging the use of wave power. 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," says Professor John Chaplin, who is leading the EPSRC-funded project.