The Lake Erie Energy Development Corp. (LEEDCo) says that the Icebreaker offshore wind project planned for the Ohio waters of Lake Erie will use an innovative foundation design developed in Europe. ‘Mono bucket’ foundations, developed by Denmark-based Universal Foundation (UF), will significantly reduce installation costs for the pilot project compared to the modified monopile concept that LEEDCo developed in 2013.
To evaluate the mono bucket design, LEEDCo considered its technical performance, manufacturing costs, installation costs and comparative risks. LEEDCo's evaluation team included veteran offshore wind engineers from U.K.-based Offshore Design Engineering and wind industry supply chain experts from Cleveland-based GLWN, formerly known as Great Lakes Wind Network.
The mono bucket foundation is an all-in-one steel structure consisting of a monopile shaft attached to a large-diameter bucket. It is installed with a unique suction system that requires no pile driving or dredging – eliminating noise and soil disturbance. According to LEEDCo, a prototype has been supporting a 3 MW turbine in Denmark since 2002. A second prototype has been supporting a met mast at Horns Rev 2 in Denmark since 2009.
In 2011, UF was selected as one of four finalists in the Carbon Trust Offshore Wind Accelerator (OWA) competition, an initiative led by the nine largest utilities in Europe to identify and de-risk promising technology innovations in the offshore wind industry. Backed by the OWA program, UF successfully installed two met masts at Dogger Bank in the middle of the North Sea in 2013.
A year later, UF completed a series of 29 successful trial installations in various challenging soil conditions off the east coast of England. This campaign was a joint effort among the UF, the Carbon Trust, Statoil, DONG Energy, E.ON and Statkraft. In addition to Icebreaker, the mono buckets design is also being considered for a number of European projects.
UF will join LEEDCo's team to complete the detailed design of the mono bucket foundations for the Icebreaker project. The team will work closely with U.S. steel fabricators to ensure the design is optimized for fabrication in the U.S. The final design will be complete in early 2016.
Caption: Two mono bucket foundations being installed at Dogger Bank, located off the U.K. coast.