Stream of power

ScottishPower Renewables is evaluating three separate coastal sites for the development of the world’s largest tidal stream projects.

Two of the sites are being planned in Scotland, in the Pentland Firth and the Sound of Islay, with the third off the North Antrim coast in Northern Ireland.

ScottishPower Renewables expects planning applications to be submitted to the Scottish Government and Northern Irish Assembly in summer 2009.

Each site is being evaluated with a view of installing between five and 20 tidal turbines. With each turbine having an installed capacity of 1MW, this could lead to a combined output of 60MW – enough green energy for over 40,000 homes. Following planning approval, the projects could be operational by 2011.

All three projects are expected to deploy the Lànstrøm tidal turbine developed by Hammerfest Strøm, a company jointly owned by ScottishPower Renewables, StatoilHydro and Hammerfest Energi.

The device’s name reflects the Norwegian and Scottish collaboration – being a combination of the Gaelic ‘làn’ meaning ‘full’ and the Norwegian ‘strøm’ meaning ‘tide’.

Lànstrøm’s technology is best described as an underwater wind turbine, but with much shorter blades and slower turning. The units are mounted on the sea bed and aligned to the tidal flow. Each device will generate around 1MW of output, while future arrays of multiple devices are anticipated that could generate 50MW to 100MW each.

‘Scotland has the best tidal resources in Europe, with the Pentland Firth alone containing enough tidal energy to meet a third of Scotland’s power requirements,’ said Keith Anderson, director of ScottishPower Renewables.
ScottishPower Renewables is part of the Iberdrola Group, the largest renewable energy provider in the world. Iberdrola have committed to investing €1.2bn (£0.96bn) in the development of renewables in the UK between 2008-2010. Beyond this, ScottishPower Renewables plans to have a renewable generating capacity of 1800MW by 2012.

The Lànstrøm tidal turbine has already been put through an extensive four-year testing regime in Norway. The device will now complete final testing in Scottish conditions, ahead of full deployment of the technology at the tidal farms from 2011.