Giant 'sea snake' harvests wave power

Posted by Emma Woollacott

GOSPORT, UK - A rubber wave power machine that looks like a giant swimming sea snake could soon be generating enough power for 50,000 homes in the UK.


The Anaconda is about 200m long and consists almost entirely of a rubber tube - both resilient and ecologically sound, say developers the Checkmate Group. The idea is to anchor it to the sea bed but allow it to move with the waves; each device can power about 1,000 homes, and the plan is to deploy them in "shoals" of about 50.


The company claims the cost of the device will be lower than that of a wind farm generating the same amount of power. They should also cause a lot less fuss, as they won't be visible from the surface.


Essentially, the Anaconda is a very large water-filled distensible rubber tube floating just beneath the sea surface at right angles to the waves, with a power take off at the stern. As a wave passes, the bulge tube is lifted with the surrounding water and causes a bulge wave to be excited. This passes down the tube’s diameter like a pulse in an artery, gathering energy from the sea wave as it goes.


Resonance between the bulge wave and the sea wave allows for contonuous energy gathering. Energy from the sea wave is stored in the rubber as it stretches. The bulge wave travels just in front of the wave rather like a surfer, picking up energy as it increases progressively in size. At the end of the tube the bulge wave energy surge drives a turbine in the power take off after the flow has been smoothed.


Professor Rod Rainey of design engineering consultants Atkins, one of the co-inventors, said: "The beauty of wave energy is its consistency. However, the problem holding back wave energy machines is that devices tend to deteriorate over time in the harsh marine environment. Anaconda is non mechanical: it is mainly rubber, a natural material with a natural resilience and so very few moving parts to maintain."