Offshore wind turbines of the future should have much larger blades as this will lead to lower costs and cheaper electricity, the UK’s Energy Technology Institute (ETI) has said.
The ETI’s Helm Wind project was set up to deliver improvements to the economics of the offshore wind power station of the future.
It brought together multinational power companies with wind energy and offshore experience from E.ON and BP, power systems and engineering expertise from Rolls-Royce and the research and design capabilities of the University of Strathclyde.
Offshore wind turbines have generally been designed for onshore use and then adapted for deployment at sea. This has led to high capital and operational costs, reliability issues and energy that is higher in cost than that from onshore turbines.
It is well known that there is huge potential for offshore wind to reduce carbon emissions and create economic prosperity, as well as increase ongoing energy security of supply.
But, for this to happen, the ETI says electricity costs need to be competitive with current onshore wind costs by 2020, and with conventional generation by 2050.
Annual offshore farm availability also needs to be increased to 97%-98% or better.
And technical uncertainties must be reduced to allow farms to be financed at costs equivalent to onshore wind today.
The Helm Wind project found that costs could be around 30% less than those for offshore wind turbines.
It also identified the potential for additional savings as the technology is developed further.
Dr David Clarke, ETI chief executive, said: “This project took a completely fresh look at all aspects of offshore wind turbines to identify concepts and technologies that could deliver significant reductions in the cost of energy. It examined everything from the rotor diameter and speed, the number of blades, whether they should face upwind or downwind, drive-train options and support structures.
“The project has shown that sufficient improvements could be made through technology innovation to deliver energy costs that are comparable with the current onshore wind costs, as well as identifying that the optimum turbine size for offshore is significantly larger than the current state-of-the-art ones being developed.
“The information that we have learnt from Helm Wind, along with other projects in our offshore wind programme, will now be analysed further and inform our next projects that help to provide affordable, reliable and secure energy sources for the future.”
Dr Joerg Kruhl from E.ON said: “Offshore renewables are an important part of the future energy mix here in the UK, offering huge potential for the generation of clean renewable electricity.
“Capturing this potential, however, presents a number of challenges which is why research projects such as Helm Wind are so important.
“The insights gathered from this project will help to inform future projects and we look forward to analysing the results further.”
Helm Wind was one of three ETI offshore wind projects that looked at new turbine design concepts, along with Deepwater and Nova, which have been completed.
The insights from all three projects will be used by the ETI to develop its offshore wind strategy, which is expected to see an offshore wind demonstrator project commissioned this year.