This is the permanent problem we have been deliberating over for years. A high power 1 MW unit such as the C6 has a large cross-sectional area (~20 m dia) that produces high vertical lifting forces to drive the piston pump. The foundation anchor thus has to accommodate continuous vertical oscillating forces of hundreds of tonnes. High value short duration impulsive forces can be mitigated by the small resiliency of the braided tether.
Pipelines and ships anchors generally need only to be supported by horizontal constraints which is relatively easy because plate anchors dig into the seabed more firmly when pulled laterally.
The ‘mobile’ foundations referred to in the link are really only small horizontal inching movements such as for thermal expansion.
One of the cheap ways forward that I can see is to devise some kind of embedment technique that utilises the mass that is already under the seabed. For that one might need a ‘small hole’ drill with cutting arms that increase in radius at a predetermined depth and then lock to become the embedded laterals – effectively a sub seafloor baseplate. The quantity of drilling material removed and to be replaced by concrete might be reduced by 90 %, i.e. reduced from 200 m3 to 20 m3. However this still requires a jackup rig on site.
Juke
CWE Price at posting:
3.0¢ Sentiment: Buy Disclosure: Held
