Concrete Contender for Most Cost-effective Foundations for Offshore Wind Turbines - continued
When considering economic benefit of foundation solutions, the performance of concrete gravity bases is also superior.
A recent study by MEC Intelligence compared the cost of a monopiles and jackets with gravity bases and suction buckets. The costs assumptions are based on actual values witnessed on projects and from inputs from industry experts.
The report concluded that the price fluctuations and vessel availability of steel solutions created an advantage for concrete gravity foundations.
With gravity bases constructed at a coastal fabrication yard, using concrete produced from locally-produced materials, by a local, skilled labour-force, the use of gravity foundations will also boost the local economy and UK GDP.
A typical manufacturing facility producing 50 bases per year will generate 500 to 600 jobs directly at the facility. The extraction and delivery of the concrete constituents will generate a further 100 UK jobs.
The Concrete Centre’s Interest Group for Offshore Wind member Seatower has recently delivered a demonstration project for the Fécamp partners EDF Energies, DONG Energy and wpd offshore.
The concrete gravity foundation is located 13 km off the coast of Normandy, and in deeper waters. Petter Karal, CEO of Seatower said
Cranefree Gravity foundations are generally more cost-efficient, quicker to install and less risky than current methods that use steel foundation designs. They also allow for local construction, which provides welcome economic activities to the coastal communities close to the wind farms.
Our technology will ease and speed up the construction of offshore wind farms at a time when cutting costs and risks is necessary to help the sector progress to more challenging project sites.
Cost reductions need to be achieved to meet the demands of the diminishing strike price and to provide UK consumers with a long-term supply of affordable, local, low carbon energy.
BVG Associates have stated that
The clearing prices announced for offshore wind … show that industry is reducing its levelised cost of energy (LCOE) faster than many people in the industry had expected.
Our models show that the clearing prices of £119.89 and £114.39 per MWh, awarded to the East Anglia 1 and Neart na Gaoithe projects respectively, equate to a levelised cost of energy (LCOE) of just under £100/MWh for projects with final investment decision (FID) in 2016.
With concrete gravity bases efficiencies are achievable as benefits can be gained from applying established and efficient working practices, innovation in technology and the confidence gained in the market will reduce perceived risks and hence the cost of finance.
Turbine manufacturers are already developing larger turbines with increased generation potential, but these are larger, heavier and will have an impact on tower and foundation requirements.
Concrete gravity bases provide the robustness and performance required to meet the engineering demands placed on foundation solutions and as widely reported, also represents a step change in technology that can deliver a cost saving against alternatives.
Concrete gravity bases will also meet the drivers for UK content, skills and competition required from the Supply Chain Plan.
However, these advantages are only unlocked by economies of scale. Economies of scale are delivered from a construction pipeline of projects and these rely on investment. As the Government framework from Electricity Market Reform, with contracts for difference (CfD) and supply chain plans roll out, we get ever nearer to the growth in low carbon energy that will benefit the construction industry and UK consumers.