WindCrete: Concrete floating platform for wind turbine
Monolythic concrete structure including both the spar buoy and the tower in a single member without any joint.
Benefits
- Integrated concept of an offshore wind floating platform plus tower for supporting the wind turbine, without any joint
- Low cost installation, without jack up vessels
- High reliability against marine environment
- Enhanced durability (> 50 years): concrete & w/o joints
- Easy to manufacture large scale w/o highly skilled workforce
- Attractive levelized cost of energy (< 15 €ct/kwh)
Issue
Currently, offshore wind turbines installation is based on fixed platforms, which increase the cost of energy at greater depths. From 60-100 meters deep solutions grounded in the seabed are not economically viable. Because of the limited area available with shallow waters the future of the offshore wind market is linked to the successful development, deployment and cost reduction of floating substructures for wind turbines.
The main factor hindering market development is the current cost of floating substructures, estimated to be twice as much as existing grounded in the seabed, and driven essentially by the cost of steel.
Solution
Monolythic Floating platform for deep sea offshore wind turbines using low cost materials, which offers an affordable technical solution for the exploitation of the best wind resources, especially due to its specific focus on concrete as the main material (with a 35% of CAPEX compared to steel).
To prevent cracking and fatigue in the marine environment, the structure is
completely post-tensioned with steel tendons in a longitudinal direction. The ballast makes use of black slag, a by-product of electrical furnaces, to reduce costs and its environmental footprint.
In addition, the design service life of the concrete structure is 50 or more years with almost no maintenance, whereas the steel one is expected to last 20 years or less, with significant maintenance costs. CAPEX and OPEX reductions produce a significantly lower Levelised Cost of Energy (LCOE).