Wednesday, 4 November 2009

Harnessing Irish wave power

The Atlantic coast of Ireland has some of the highest concentrations of wave power in the world. If this power is harnessed, it can be turned into electricity. So since 2005, the Hydraulics and Maritime Research Centre (HMRC) in Cork has been working with industry (Ocean Energy Limited) to develop a prototype wave-power electric generator. The aim is to produce 500 MWs of electricity from ocean energy by 2020.

Says Tony Lewis, the director of the Hydraulics and Maritime Research Centre at University College Cork (UCC) "The smallest scale that we use is this one-to-fifty scale which gives us an idea of how the concept will work, and when we get that then we scale up further to this one-to-fifteen scale model which then allows us to simulate, in a much more realistic way. The principle that it operates on is that there is a large ducting, or chamber, inside this device which is open to the sea at the rear and inside the chamber there is an air volume. That air volume is compressed by the waves and as the waves go by that compressed air is forced through the turbine which spins to generate electricity."

After three years of experiments in the wave tank, a larger quarter-scale test device was moored one and a half miles off the coast of Galway on Ireland's west coast. For the engineers on the project, designing a platform that could survive the harsh seas of the north Atlantic was the biggest challenge.

Says Richard Toll, research professor Economic and Social Research Institute in the Irish capital Dublin, "'The reason why wave power is so expensive is two fold – first, very few people live in the ocean, it's simply a long way away from where we need the electricity and that increases its cost and the second reason is that the environment is so hostile." But while wave power is expensive compared to other renewable such as wind, those costs should come down as the industry is scaled up. The future for wave power could still be bright.