Talisman and Scottish and Southern Energy (SSE) originally described the Beatrice project of 2 Repower 5 MW turbines as the forerunner of a 200-turbine wind farm in the area. Even though Talisman is selling its Beatrice oil field to Ithaca Energy Inc, its wind plans remain intact. The sale does not include its interest in the wind project, which will continue to provide power for the Beatrice platform. The two turbines are located alongside the platform, 25 kilometres from the coast in waters 44.3 metres deep and with a tidal range of nine metres.
MacAskill insists that for the energy sector, 50 metres is "not deep." A number of companies offer technology and installation techniques developed for the offshore oil and gas sector that would be suitable for installing wind turbines in water depths of that range, but not in shallower waters, he says.
Talisman and SSE led the 18-strong consortium involved in the Beatrice project, which had additional funding from the EU and UK and Scottish governments. As the deepest offshore wind project in the world, Beatrice boasts a number of "firsts", says MacAskill. It is the first application of a jacket substructure in offshore wind, the first onshore assembly of tower, nacelle and blades, and the first offshore installation from a floating vessel. It is also the only offshore application of 5 MW turbines. "We have pioneered the development of deepwater turbines; we have shown it can be done," he states.
Talisman is now discussing with technology suppliers how to move cost effectively from two machines to a much larger wind farm. In particular, Burntisland Fabrication, which manufactured the substructures for the two turbines, is considering how it can optimise the design of the equipment and layout of its Fife yard to producing at least one a week. This could lead to a cost reduction of some 40-60% compared with the years it took to prepare the substructures for the demonstrator project, says MacAskill. "We have a willing supply chain. We are now trying to make similar progress [on cost savings] in other areas, including onshore assembly and cable-laying," he says.
Turbines in deeper waters are the future for offshore wind, believes MacAskill. He comments that in the early days of the Beatrice project "people thought we were nuts." But moving further offshore avoids conflicts with other uses of the marine environment such as fishing, birds, leisure traffic and shipping lanes. Moreover, many of the projects now being considered in other parts of Europe are in seas of a similar depth, he points out. "What we are talking about is going to be the norm in the medium term."