The golden age of wave power
Thirty years ago wave power was the energy of the future. John Chaplin, a Professor at Southampton University, states ‘there was a golden period back in the 1970s where a lot of progress was made but it came to a halt. In the last few years it has all come back.’ Chaplin and his colleagues who are involved in the Anaconda project are back at the forefront of this progress.

The Anaconda is a simple rubber snake-like device designed to sit just below the surface of the sea, facing the waves. As a wave passes along it, a ‘bulge wave’ is formed in the elastic wall of the Anaconda tube, and the wave outside pushes this, making it bigger and bigger until it finally produces a surge of water which turns a turbine and the resulting power is fed back to shore. Chaplin is leading the EPSRC funded project study which is concerned with the complex interaction between the tube and the sea. The Anaconda power generation system is being developed by Checkmate Seaenergy in conjunction with its eminent inventors, scientists Professor Rod Rainey, a leading expert on floating offshore structures and Professor Francis Farley, who has also been working on wave energy since the mid 1970s.

Survival factor
‘Survivability is the number one criterion for any wave energy device,’ says Chaplin, and this is what has people excited by its possibilities. ‘It has to work in normal wave conditions but it also has to survive more hostile conditions when there is a big storm. The Anaconda is much more likely to be able to survive extreme conditions.’

The other advantage is that its movement can match the speed of the waves which means you can harvest the energy. As Chaplin explains, any such wave device ‘has to have a natural frequency close to the wave frequency,’ and normally this is very challenging. ‘With the Anaconda you can arrange it so that the speed of the water waves matches the speed of the bulge waves and inherently tune it that way.’

Flexible
‘The next stage of testing’, says Chaplin, ‘will involve exploring the basic physics of why it works and how you can make it better.’ It’s a bit more difficult because, ‘it’s not like a ship or an offshore structure, which is what we would regularly work on. The Anaconda is so flexible that it responds in a different way in waves and that’s all part of the challenge.’ Then they have to be able to extract the power to make electricity and the results so far are very encouraging.