JDR has worked closely with the world’s leading renewable energy organisations to deliver a range of subsea solutions for wave power transfer and export.

The engineering and manufacture of the dynamic power umbilical for Ocean Power Technologies’ PowerBuoy® wave energy device marked a key milestone in JDR’s investment in the offshore renewables sector. The PowerBuoy® converts ocean wave energy into useable electric power for utility-scale grid connect applications.

JDR’s dynamic power umbilical incorporates 3.3kV 3phase power cores and fibre optic cables for data transfer and provides the vital connection between the PowerBuoy® and the underwater substation pod which collects and transforms the power. Wave Energy Converting systems must withstand some of the harshest environmental conditions on earth. Salt water and blistering solar effects present a variety of corrosion and integrity challenges, whilst stormforce winds and swells generate extreme dynamic wave motion. These constant factors place intense loads on the system and require high flexure endurance of the cable.






High Strength Termination Assembly
JDR developed an innovative installation technique for the project. A custom designed buoyant termination mechanism was employed that reduced installation costs by eliminating the need for an ROV or diver during installation at sea. To ensure the 20 year lifetime requirement, Trelleborg’s BSR was applied on the termination components.

Qualification Testing
JDR performed extensive inhouse qualification testing on the umbilical system including the floats used to hold the cable in an “s-curve” once installed. The tests included elongation, rotation and torque measurements of the cable while undergoing specified load patterns. Tensile failure testing determined the ultimate strength. Tension-tension fatigue of the product was undertaken and 1 million bending cycles along the floats was performed to simulate the constant bending motion the umbilical will see throughout its lifetime.