Riding along on the crest

What’s claimed to be the world’s first commercial wave power station has successfully fed electricity into the UK’s national grid, on the Scottish island of Islay.

Jointly developed by Wavegen and Queen’s University Belfast (QUB) with support from the EU, the Limpet system, as it is called, is rated at 500 kW and able to provide enough electricity for about 400 local homes.

The station itself has secured a 15 year power purchase agreement with the major Public Electricity Suppliers in Scotland.

Established in 1992, by Professor Alan Wells FRS inventor of the Wells Turbine, Wavegen has developed a range of energy modules to exploit wave energy resources in the shoreline, near shore and offshore environments.

Wavegen’s devices comprise two basic elements: a collector to capture the wave energy and a turbo generator to transform the wave power into electricity.

The wave energy collectors used in Wavegen’s are in the form of a partially submerged shell into which seawater is free to enter and leave. As the water enters or leaves, the level of water in the chamber rises or falls in sympathy. A column of air, contained above the water level, is alternately compressed and decompressed by this movement to generate an alternating stream of high velocity air in an exit blowhole. If this air stream is allowed to flow to and from the atmosphere via a pneumatic turbine, energy can be extracted from the system and used to generate electricity.

Wells turbines are used to power the electricity generators. Wells turbines have the unique property of turning in the same direction regardless of which way the air is flowing across the turbine blades. Thus, the turbines continue turning on both the rise and fall of wave levels within the collector chamber. The turbine drives the generator, which converts this power into electricity.

More on the web at http://www. wavegen.co.uk