UK: Suction Bucket Foundation – Innovation that Saves Time and Money
An innovative solution for offshore wind sector, developed by Danish company Universal Foundation, will majorly drive down the costs that developers face when constructing offshore wind farms and will save time of foundations installation.
The suction-installed Bucket Foundations, called the “suction bucket”, cost 20% less than standard foundations and will save developers over GBP 5 billion if used for the 6,000 wind turbines, which are planned to be erected in the next decade, Phil de Villiers from Carbon Trust is cited by The Guardian as saying.
Dogger Bank offshore wind farm will see the first deployment of two of the foundations on Monday, when they will be installed 25 metres deep in the sea.
How does it work?
The Bucket Foundation combines the benefits and main proven aspects of a gravity base foundation, a monopile and a suction bucket into one product. It includes a patented cost efficient installation system which controls the vertical alignment of the total foundation as it sucks itself into the seabed reducing total installation time significantly.
Being lowered upside-down into the seabed, a quicksand is created around the rim of the bucket with a pipe that runs up through the stem above sucking water out of the bucket. When it firmly sinks into the seabed, the pump is turned off.
“Trying to pull it out creates a vacuum in the bucket, like when you try to pull your foot out of wet sand on the beach,” The Guardian cites Søren Nielsen, technical director at Universal Foundation, as explaining how the very strong foundation is formed using this technology.
The advantages of the Bucket Foundation are:
– Capability to accommodate a broad range of site conditions, loadings and operational performance requirements
– Fast and controlled all-in-one unit: the installation process has no dependency on jack-up vessels; no requirement for seabed preparation; no diver operation required; no requirement for a transition piece eliminating the need for a grouted connection.
– No pile driving eliminating the associated environmental concerns regarding noise and avoiding ‘no pile driving’ periods in the year.
– Reduced or no need for scour protection.
– The suction operation can be reversed allowing complete removal of the foundation: re-use and re-deployment of met masts and equipment into other locations;
– The foundation weighs less than traditional foundation structures.
Press release, January 25, 2013; Image: Forewind