What is clear is that moving into deeper and further-from-shore waters is almost as big a logistical step up as moving from land to near-shore waters was a decade or so ago. Transferring people, equipment and components to a site over 200 kilometres from shore - the distance to a large portion of the North Sea's Dogger Bank project - in waves regularly pitching up at 2-3 metres is a very different challenge to dashing from port to nearby wind site and back in a day.
The remoteness and scale of the next generation of offshore wind farms means stationing people at the site on a permanent, rotating basis. This applies to both the construction phase as well as to maintenance activities, which will then continue throughout the wind farm's 20-year operational life span.
Whether this is done through the use of large "mothership" bases or fixed accommodation platforms is, as the articles in this report show, open for discussion. Both have their merits, as does the use of helicopters to augment vessels for rapid access and in conditions where vessels cannot operate.
As well as the accommodation vessel versus rig debate, there are also different schools of thought when it comes to the use of specialised vessels versus multifunctional ships that can carry out a number of tasks simultaneously. Specialisation will continue to dominate the construction phase of offshore wind, with vessels for tasks such as underwater exploration, foundation construction, tower installation and cabling seeing ongoing design enhancements. Operations and maintenance may be a more appropriate area for more multi-functional vessels.
Much time and money has been spent developing foundation, turbine and cabling technology for deployment at sea. Research and effort has gone into designing next-generation vessels aiming to deliver more efficient, safe and cost-effective solutions for deployment in deeper water and further-from-shore locations. Many of these new vessels have yet to be built, but now it is up to the wind industry to ensure it has the transport in place that means expensive offshore assets can not only be effectively built but also maintained around the clock in a hostile and increasingly distant environment.
Paul Garrett is associate editor of Windpower Monthly.