200 wind turbines plan for North Sea 

Engineers last week unveiled the largest wind turbines ever connected to the UK national grid: two massive generators that tower 300ft over the North Sea 15 miles from the Scottish coast. Now the project’s backers say they are preparing plans to construct 200 of these huge turbines, creating a gigantic wind farm with the capacity to provide power for an entire city.

Both the devices erected in water 150ft deep in the Beatrice oil field are fitted with three 200ft blades and can generate 5 megawatts of power, enough to supply a village with electricity.

‘We have shown this deep-water wind technology works, that it could be made to operate economically, and that it could be used to generate a significant amount of power far from shore and shipping lanes,’ said Allan MacAskill, director of the Beatrice Wind Farm Project.

The project – backed by Scottish and Southern Energy and Canadian oil exploration company Talisman – has pushed wind technology to its limits. Designing the huge lattice jackets on which the turbines stand, and fastening these to the ocean floor, provided engineers with major headaches that took months to overcome.

‘The turbines are German but the technology involved in fastening them to the sea bed, and making them work in deep water, comes from Scottish expertise gained from its North Sea oil work,’ said Paul O’Brien, a renewable energy expert with Scottish Development International. ‘We are good at putting things in the water and keeping them there.’

Developing wind farms far offshore may prove crucial in helping Britain cut its carbon emissions, as onshore wind farm projects are finding it increasingly difficult to get planning approval because opposition to them is becoming more entrenched and better organised.

Offshore farms cost more to build but produce more electricity because they usually stand in open, windier spots. However, current offshore farms can encroach on shipping lanes, affect seabird sanctuaries and disturb marine life, limiting the number of suitable sites.

Shallow-water offshore farms – such as the Kentish Flats farm in the Thames Estuary – miss out on some of Europe’s strongest winds: those that howl across the North Sea’s northern stretches. ‘With the expertise we have gained with the Beatrice project, we can exploit winds that simply cannot be tapped by offshore turbines at present,’ added O’Brien.

However, wind energy farms are not a simple panacea for the country’s energy problems. Last week the Beatrice turbines were being serviced but, if they had been operational, they would not have been turning. The North Sea’s winds were virtually non-existent, meaning no power would have been generated.

Opponents say such variability of output is a drawback of wind energy. But O’Brien insisted: ‘If we can build big turbines far away from the shore, they will cause minimum upset and disruption. This is their future and that is why the Beatrice project is so important.’

Robin McKie, science editor
The Observer

guardian.co.uk

14 October 2007