Prototype wave-powered electricity generator under evaluation near Portnahaven on the island of Islay, Scotland. The device is built at the head of a natural rock gully and encloses a column of sea water. Waves entering the gully are channeled in towards it, causing the column of water to rise and fall. This forces air through a Wells turbine, which turns in the same direction whichever way the air is flowing, driving a 200 kilowatt electricity generator. The device was designed and developed by researchers at Queen's University, Belfast, and will eventually be used to supply electricity to small, isolated communities.