Call for entries from companies and consortia interested in undertaking a study for the OWA Foundations Technical Working Group (TWG-F) to develop a better understanding of the remaining soil capacity left from relief drilling of large monopiles for offshore wind turbine generators, to better inform monopile design.

The progression of drill size for XXL monopiles is accelerating due to the projected need across the industry. However, the lack of knowledge of the remaining soil capacity left from the relief drilling or underreaming, such as uncertainty in axial/lateral capacity of the disturbed rock layers, brings risks for pile design.

The main objective of this study is to investigate the interaction of drilled monopiles in rock with a focus on developing a better understanding of the remaining soil capacity left from relief drilling for large monopiles. In addition, gaining a better understanding of the constraints of the drilling equipment is also key.

The expected benefits of this work are anticipated shorter timescales for fulfilling the hurdles for individual projects and gaining more certainty on feasibility. In addition, developing more certainty on pile embedment length is expected to be a benefit from the knowledge developed in this study.

The deadline for clarification questions is 8 May 2024 at 13:00 BST.

The closing date to receive tender submissions is 31 May 2024 13:00 BST.

All clarification questions and tender submissions should be sent electronically, by their respective deadlines, to alicia.stammers@carbontrust.com with tom.wishart@carbontrust.com in copy.