Wave power ‘hotspots’ mapped

Researchers considered the balance between the amount of wave resources and the cost of generating power at particular locations

Up to 42TWh of energy could be extracted from UK waters each year if wave-power devices are located in designated “hotspots”, according to a report by the Carbon Trust. 

This potential wave energy is equivalent to 11% of the country’s current power generation, said the report. The researchers identified the hotspots by considering the best balance between the amount of wave resources available and the cost of generating power at a particular location. An area 100km offshore to the west of Scotland on the edge of the continental shelf scored highest.

Charlie Blair, technology acceleration manager at the Carbon Trust, explained: “As you
go further offshore you get bigger waves and that means your energy can be cheaper, but some of your costs also increase.” Energy firms incur higher costs for operating, maintaining and connecting to the grid devices further offshore, for example.

Wave-power devices are still at the prototype stage, so they are situated close to the shore, Blair added. The devices will require further development before they can be used in the offshore hotspots. He suggested that the Pelamis wave-power device would need to be made broader and longer and the AWS Ocean Energy device would need to be resized. 

Commenting on the research, Professor Stephen Salter, from the wave-power group at the University of Edinburgh, said the amount of potential energy could be even higher if the most advanced devices were developed.

“My view is that it is about double what they are saying. If you go into deeper water, there is much less attenuation by friction on the seabed,” he said. Previous estimates of wave-power potential have been based on devices located closer to shore. In shallower water, devices can lose up to two-thirds of the energy coming in, he said.