‘World’s most powerful’ subsea trencher to bury power cables 18 feet below seabed
A new subsea trencher, the NKT T3600, has arrived at the UK’s Port of Blyth for fit-out and commissioning.
Designed and built by UK original equipment supplier Osbit, the machine will be put to use by Danish power cable manufacturer and installation firm NKT.
The NKT T3600, described as the world’s most powerful subsea trencher, will be capable of burying cables to depths of up to 5.5 meters below the seabed. The massive machine will help to meet the high demand for high-voltage power cables required for renewable energy operations.
NKT T3600: The world’s most powerful subsea trencher
NKT announced its investment in the NKT T3600 trencher in June 2025. A month after that announcement, NKT entered into a four-year frame agreement with Helix Robotics Solutions Group.
As an Offshore Energy report explains, the agreement included the installation, offshore operations, maintenance, and project engineering for the subsea trencher. Under the agreement, Helix would also deploy the machine using its own support vessel.
UK-based firm Osbit designed and built the trencher, as well as its launch and recovery system (LARS), at its UK facilities.
The NKT T3600 was designed to strengthen the offshore power cable ecosystem and bolster the transition to renewable energy. The massive machine will be capable of delivering 3,600 horsepower, allowing it to bury cables deep into the seabed. Utilizing both a jetting and cutting function, it will be able to operate in a variety of soil conditions.
Protecting critical cable infrastructure
NKT has announced that the T3600 subsea trencher is scheduled to be commercially operational in 2027. In the meantime, the Danish firm is also investing in enhanced cable protection technology, according to Offshore Energy.
In a LinkedIn post, the company noted that “the investment in the NKT T3600 not only supports the local UK economy but also improves the security of energy supply through the protection of critical cable infrastructure.”
When NKT originally revealed its NKT-T3600 investment, the company’s Executive Vice President and Head of HV Solutions, Darren Fennell, said, “Protecting power cables is more important than ever due to the increased risk of sabotage and high activity at sea.”
Speaking of the NKT-T3600, he noted that the trencher “will be best in class, ensuring reliable deep-burial protection of power cables in even the most challenging soil conditions. With this investment, we also support the local economy by engaging UK companies in the design and development of the trencher.”