Thinner suction bucket concept awarded grant

DENMARK: A consortium comprising Siemens Gamesa, Fred Olsen Windcarrier and Aalborg University claims its industrialised suction bucket design is capable of reducing the thickness of the steel plate used in the previous foundation design.

The suction bucket prototype will be tested towards the end of this year (pic: Universal Foundation)

The group, which also includes Fred Olsen-owned, mono-bucket specialists Universal Foundation and Offshoreenergy.dk was awarded a €3.8 million grant to perform test installations of the concept, as part of Denmark’s Energy Technology Development and Demonstration Programme (EUDP).

By adopting industrialised fabrication methods using coil steel — instead of classical plate steel — the plate thickness can be reduced to below 20mm, compared to the 30-40mm range typical for suction bucket foundations, according to the consortium.

Siemens Gamesa’s Finn Daugaard Madsen, the project manager, explained that this would reduce the amount, and therefore cost, of steel used and enable higher supply availability.

He added the assembly process is more suited to high-volume manufacturing and would help to reduce supply bottlenecks.

Meanwhile, Søren Andreas Nielsen, head of research and development (R&D) at Universal Foundation, said the concept could cut total system costs by 40% compared to foundations using traditional fabrication methods.

The new concept can also be installed with lower noise levels than traditional monopile foundations, the group claimed.

The suction bucket concept to be tested has already been designed and an 8x8-metre prototype has already been fabricated, the partners added. It will be tested towards the end of 2018 depending on vessel availability.

Siemens Gamesa and Danish steel specialist Ib Andresen Industri originally developed the concept for application in onshore towers.

The consortium aims to mature the industrialised suction bucket concept towards full commercial scale.