UK body warns on foundation tests

UK government-industry technology body the Carbon Trust (CT) has warned that many of the innovative high-load wind turbine foundation designs being developed for use off Europe may end up shelved if demonstration sites are not immediately made available.

The problem has become so pressing, it claims, that without a quick solution the next-generation jackets and concrete-gravity bases now at prototype phase will not be ready in time for the major roll-out of UK Round 3 projects, which are expected to deliver up to 18GW of new generating capacity by 2020.

"At present we have a Catch 22.  We have the technology but we have no way of proving that it can work at scale because we currently have no suitable offshore demonstration sites in the UK ready to use," says CT head of offshore wind Phil de Villiers.

"The bottom line is that unless we sort this issue out in the next few months we could be putting at risk the mass roll-out of major new cost-saving technologies which, in turn, can help reduce the overall offshore wind build bill by billions of pounds.  

"We have a duty to ensure we hit our carbon targets at the least cost possible, so it’s in everyone’s interest, including the government, the industry and consumers, to fix this problem and fix it fast,” he added.

The UK currently has two main offshore testing sites under development, Narec's Blyth Offshore Wind Demonstration Site off northeast England, and the European Offshore Wind Deployment Centre (EOWDC) off Aberdeen, Scotland – but neither is yet open for business. 

The alert from the CT comes as the UK Crown Estate today announced a new leasing programme designed to boost investment in a range of offshore wind test and demonstration projects that would pave the way toward commercialisation of high-capacity turbines, including floating concepts, foundations and other key technologies.

Foundations currently account for about 30% of the capital cost of an offshore wind farm.

The cost of offshore wind energy is currently around £140-£150/MWh ($219-$234), but CT calculations suggest innovations "in a number of key areas" including new foundation designs could reduced this figure by up to a third, down to around £100/MWh. 

"This level of cost reduction won’t happen unless new innovations are properly tested in situ to provide developers and financiers with technical assurance before undertaking major multi-billion pound procurement programmes," says de Villiers.

The CT, through its Offshore Wind Accelerator initiative has backed four new foundation designs, including the Universal Foundation, which can be installed without piling as it uses a giant suction bucket to bury the steel structure into the seabed, and the Keystone twisted jacket structure, a design that cuts cost by using less steel than traditional foundations.

Prototypes of the Keystone and Universal Foundation designs fitted with met-masts have already been installed in UK waters, but have yet to be demonstrated with large-diameter wind turbines.

Another CT-supported concept, MarCon's self-installing MWP Mk2 jack-up tripod, is said to be "very close" to being mated with a turbine for the first time after a year working as a met-mast foundation at E.On's Södra Midsjöbanken development site off Sweden.