Enhancement of the seafloor CPT - a solution to acquire improved in situ data earlier, faster and greener

The offshore wind industry relies heavily on cone penetration testing (CPT) for site characterization of wind farm sites. The CPT performed in downhole (drilling) mode has the largest impact on the detailed site investigation costs and drilling vessel time. Due to the unprecedented growth in the global offshore wind, there is a supply bottleneck of drilling vessels. To mitigate this issue, advancements in seafloor CPT systems (non-drilling mode) can provide improved in situ data, by comparison, earlier, faster, cheaper, and not least, greener. A recent study on an offshore wind farm in the North Sea showed that a seafloor CPT system enhancement successfully reached target depths in 50% of locations. This paper highlights the advantages of upgrading seafloor CPT systems, demonstrating that enhancements such as increased thrust capacity, improved cone sensor capacity, mechanical friction reducers, and rod lubrication systems can significantly reduce data acquisition timelines and thus achieve significant cost and emission savings