Cable vessels, CTVs and subsea support tonnage expand across offshore energy markets
Fleet investments and contract awards across the offshore vessels sector highlight continued momentum in both renewable and conventional offshore markets.
In this compilation of offshore vessel news, recent developments, including high-capacity cable-lay vessels (CLVs), next-generation crew transfer vessels (CTVs), subsea survey campaigns and North Sea support contracts, underscore tightening vessel demand and the expanding role of specialized tonnage in offshore wind, decommissioning and infrastructure support.
Cable & electrification vessels:
Boskalis plans high-capacity cable-lay vessel addition
Royal Boskalis plans to order a new high-capacity cable-lay vessel in response to the growing need for long-distance cable installations for offshore wind and interconnector projects.
Demand is especially strong for high-voltage direct current cable-laying capability.
The new CLV, which should enter service in 2029, will be equipped with two 12,000-t cable carousels, including a concentric carousel.
Its layout will be optimized for installation of longer, continuous cable sections, reducing the volume of cost-intensive offshore joints and supporting enhancing long-term cable integrity, the company said.
Over the past 15 years, Boskalis has performed installations for more than 140 subsea cable-related projects. Its current fleet for this market includes three construction lay vessels, a trenching support vessel and other trenching equipment.
Nexans receives cable-lay vessel
Nexans has taken delivery of a new cable‑laying vessel, the CLV Nexans Electra, built at the Ulstein Verft shipyard in Norway.
The CLV is 149.9 m long and 31 m wide DP3, and the vessel has been designed for offshore wind connections and high‑voltage interconnector systems. It is said to be an evolution of the CLV Nexans Aurora, with expanded capacity for the coming larger scale offshore electrification projects.
Features include:
- Three turntables with a combined cable capacity of 13,500 t;
- Capability to bundle‑lay up to four cables simultaneously;
- Subsea tooling, with jetting and burial systems; and
- Hybrid power system that can operate on biodiesel blends, cutting emissions.
North Sea support & subsea activity:
North Star secures ERRV contracts across 17 North Sea vessels
North Star has won a series of new and renewed emergency response and rescue vessel (ERRV) contracts covering 17 vessels in the North Sea, totaling about 50 years of combined contract duration. The multi-million-pound awards, secured through tenders and extensions, highlight continued operator reliance on ERRVs to support offshore safety and production stability across the UK Continental Shelf.
The company said the contracts "reflect the strength of North Star’s long-standing relationships with offshore energy operators."
The contracts support about 435 offshore roles and reinforce North Star’s position in providing continuous safety coverage to roughly 50 offshore installations.
AGR adds OSV for North Sea P&A and decommissioning campaigns
AGR has partnered to onboard the multipurpose Aquaman II offshore support vessel (OSV), expanding its marine capabilities for North Sea subsea operations, plug and abandonment (P&A), cable work, and decommissioning campaigns.
The vessel will be configured as a light construction AHTS, combining towing and anchor-handling with subsea capabilities including a work-class ROV and active heave compensation system.
Wind logistics & project prep:
Mainprize orders Supa Swath crew transfer vessels
In Singapore, Strategic Marine has signed shipbuilding contracts with Mainprize Offshore for two new 33-m aluminum Supa Swath crew transfer vessels (CTVs).
The Walker Marine Design CTV is said to provide various upgrades on the proven 26-m Supa Swath platform. These include:
- An extended waterline length of 30 m;
- An expanded 13-m beam;
- Increased fuel oil capacity of more than 63,800 liters to enable longer operational endurance; and
- A passenger capacity of 39 personnel, up from 27 on the 26-m design.
In addition, the new design is said to offer 360-degree visibility from the wheelhouse and a 140-sq-m deck cargo area with a load capacity of up to 50 mt. The two Caterpillar C32B engines and twin four-blade controllable pitch propellers deliver speeds of up to 30 knots.
TenneT awards North Sea cable route survey
Next Geosolutions has secured a new contract from TenneT to perform marine survey activities in the Voordelta – Nederwiek 3 offshore wind area in the Dutch North Sea.
The survey, for TenneT’s Roadmap 2030 project, will assess the technical feasibility of the planned cable corridor, identify potential seabed obstacles, and support the design and engineering of the infrastructure.
TenneT is looking to limit operational risks during installation of the export cables connecting the offshore wind area to onshore facilities.
NextGeo will conduct geophysical and geotechnical marine surveys along the cable route, based on the acquisition and processing of geophysical data for seabed mapping.
In addition, the company will undertake geotechnical sampling and analyses down to 40 m, to characterize the subsoil, and identify any unexploded ordnance and obstacles along the route.
Operations should be completed by the third quarter.
About the Author
Jeremy Beckman
Editor, Europe
Jeremy Beckman has been Editor Europe, Offshore since 1992. Prior to joining Offshore he was a freelance journalist for eight years, working for a variety of electronics, computing and scientific journals in the UK. He regularly writes news columns on trends and events both in the NW Europe offshore region and globally. He also writes features on developments and technology in exploration and production.
Ariana Hurtado
Editor-in-Chief
With more than a decade of copy editing, project management and journalism experience, Ariana Hurtado is a seasoned managing editor born and raised in the energy capital of the world—Houston, Texas. She currently serves as editor-in-chief of Offshore, overseeing the editorial team, its content and the brand's growth from a digital perspective.
Utilizing her editorial expertise, she manages digital media for the Offshore team. She also helps create and oversee new special industry reports and revolutionizes existing supplements, while also contributing content to Offshore's magazine, newsletters and website as a copy editor and writer.
Prior to her current role, she served as Offshore's editor and director of special reports from April 2022 to December 2024. Before joining Offshore, she served as senior managing editor of publications with Hart Energy. Prior to her nearly nine years with Hart, she worked on the copy desk as a news editor at the Houston Chronicle.
She graduated magna cum laude with a bachelor's degree in journalism from the University of Houston.