Keeping the CTV fleet moving

Sonihull, the world’s leading ultrasonic antifouling technology, is helping to keep the global Crew Transfer Vessel fleet moving

“Our ultrasonic antifouling systems have a long and successful history in the offshore wind sector,” says Darren Rowlands, CEO of Sonihull. “It’s only natural that we are now also a big part of the story when it comes to keeping CTV’s operating efficiently and reliably. Recent market growth has seen a marked increase in demand across multiple applications from monopiles to CTVs.

In the early years of the offshore wind industry, engineering crews were transferred to wind farm installations in vessels more akin to pilot boats than current designs. As the sector has grown and designs have homologated, Crew Transfer Vessels, or CTVs as they are now known, have developed into their own specialist niche.

Modern CTV designs have been developed specifically to expedite the safe delivery and collection of technical crews to and from windfarm installations. They need to be fast, comfortable, stable and capable of staying on-station in a wide variety sea states and weather conditions. Most importantly, like all commercial vessels, CTVs must be reliable. If the vessel is not working it is not making money and vital installation or maintenance work may be delayed.

In recent years, as the world’s energy-production profile transitions away from fossil fuels towards low CO2 and renewable sources, the demand for CTVs has risen sharply. Getting an increasing number of technicians to work on a growing number of offshore wind turbine installations has become a big opportunity for the market. There has been a newbuilding boom for specialist CTV builders and a series of high-profile acquisitions as companies look to provide one-stop-shop solutions for CTV chartering and operation services to wind farm operators all over the world.

“Sonihull is already used to keep bio-fouling at bay on offshore jackets and monopiles. Minimising operational bio-fouling reduces drag and structural loads during storms. This allows designers to decrease the initial structural steel requirements at the design stage. It also reduces decommissioning and cranage costs, because of the lack of tonnes of extra weight from weeds, molluscs and barnacles.”
“Sonihull systems have even been used to protect landing stages and ladders, preventing barnacle and mussel settlement and protecting technicians from cuts and injuries during transfer.

Now, Sonihull is also being used to keep CTVs operating efficiently and reliably. Sonihull can keep propellers and waterjets clean between major service intervals without any in-water cleaning or downtime, this keeps CTV vessels’ propulsion working in as-new condition, cutting fuel-burn and CO2 emissions. This applies to every kind of CTV propulsion system including hybrid and all-electric systems. “Wherever you have unwanted bio-fouling, Sonihull can control it.”