Seven concepts out of 100 submissions have been shortlisted as part of a multimillion-pound Carbon Trust competition to find wind turbine foundation designs suitable for deeper sea water conditions (30-60m) where the next generation of offshore windfarms will be built.
Just two of the seven consortia selected have a clearly identifiable British content. However, Scottish company Concrete Marine Solutions was not among the chose few, whereas the Wood Group is.
The lucky seven are:
Gifford/BMT/Freyssinet (UK / France) – large concrete gravity-base structure transported to site by a submersible transport and installation barge.
Glosten Associates (US) – floating wind turbine foundation based on Tension Leg Platform (TLP) technology, comprising a buoyant hull, tendons and novel anchors.
Suction Pile Technology/Wood Group (Netherlands/UK) – asymmetric suction bucket tripod foundation which can be transported from the quayside with the turbine already installed.
Keystone Engineering (US) – inward battered guide structure: three supporting legs angled around a central pile in a twisted jacket approach.
Offshore Wind Power Systems of Europe (US) – Titan platform floated into position then its three legs lowered to the sea floor, similar to a jack-up drilling rig.
Ballast Nedam (NL) – drilled concrete monopile.
MBD Offshore (DK) – suction bucket monopile. Primary material is steel, using buoyant installation and delivery.
The designs will receive up to £100,000 support for concept development, engineering analysis, commercial feasibility and technical assistance. Up to three final winners will have their designs built and installed in large-scale demonstration projects in 2010-12 with funding from a consortium led by the Carbon Trust.
The project forms part of phase one of the Carbon Trust’s Offshore Wind Accelerator (OWA) programme, which is a collaboration between five major international energy companies: DONG Energy (Denmark); Airtricity Developments (UK); RWE Innogy, parent company of RWE Npower Renewables (Germany); Scottish Power Renewables (UK), and Statoil (Norway).
This group of companies judged the submissions.
Reacting to the non-selection of his company’s concept, a concrete gravity-based structure that has featured in Energy, including in last month’s issue, Concrete Marine Solutions founder Roger Taylor said he was familiar with most of the chosen concepts and had dismissed them on “cost and practicality” grounds.
Carbon Trust selection was based on manufacturing costs, transport and installation costs; potential for volume cost savings; structural design and durability; maintainability and turbine accessibility, plus decommissioning and removal costs.
The trust described the designs as “radical” and said they offer the potential to “revolutionise” the construction of offshore windfarms, reducing costs and overcoming engineering challenges currently facing the industry.
The organisation said they provide a “glimpse of the future”, with radical concepts such as floating turbines anchored to the seabed and spider-like tripod structures.
There is no doubt that lower costs are vital if Britain is to instal the 6,000 or so offshore wind turbines needed to ensure that offshore wind meets a quarter of the nation’s electricity needs by 2020. However, that 30 gigawatts (30,000 megawatts) target looks increasingly unattainable.
The CT notes that the current price tag is up to £75billion, with deepwater foundations accounting for 20% or more of a windfarm’s total project costs. Energy believes the overall cost will be far higher as the per-megawatt-installed-offshore has now soared past the £3million mark and competition for scarce supply-chain resource intensifies. There is also the vexed question of money supply in the wake of the credit crunch.
Tom Delay, the trust’s CEO, said in a statement: “The goal of the new designs is to reduce the current costs of foundations by at least a quarter.
“This will save billions of pounds and enable the industry to deploy turbines in the much deeper and rougher sea conditions that will be experienced by the significantly larger offshore wind projects beginning in 2012 as part of the Crown Estate’s third round of licensing.
“Building thousands of turbines offshore to provide a quarter of our power needs is the greatest engineering challenge we face in the coming decade.
“Without new thinking to cut costs, many planned projects could remain on the drawing board, putting our carbon targets and energy security at risk. We must urgently re-engineer our energy system, and building offshore windfarms while creating onshore jobs must play a central role.”
While the UK alone needs more than 6,000 new offshore foundations by 2020, the global number of offshore wind turbines will reach 15,000 or more in a relatively short period. According to the Carbon Trust, this suggests a global market for foundations worth up to £2.5billion a year, which shows clear market potential for the winning designs.
It also presents a huge opportunity for fabrication yards with an oil&gas heritage to cash in on a new boom, if they are so minded.