Connecting power markets across the globe

Nemo Link HVDC

The Nemo Link interconnector project aims to improve grid reliability and access to sustainable power generation between the UK and Belgium. The challenge? The joint venture members, National Grid in the UK and Elia in Belgium, needed to deliver something unique: a 140-kilometre submarine cable between their two locations as well as substations that would allow energy to flow in either direction.

We assisted with bid evaluation, and we developed the technical specifications including a high voltage direct current (HVDC) converter station specification package. This package consisted of a description of functional requirements for the design, supply, and installation of two voltage source converter (VSC) stations as well as details for the ac/dc equipment, transformers, and buildings. A second package covered the HVDC land and submarine cable specifications, including the needs of the submarine and underground HVDC cables, terminations, splices, and auxiliary equipment.

The packages were developed to allow suppliers to optimise the voltage, either 350 kV or 400 kV, and the cable specification allowed the suppliers to propose their optimal cable—mass impregnated (MI) or cross-linked polyethylene (XLPE). With these design specifications, National Grid and Elia can deliver affordable, clean, and secure energy all while improving grid reliability for the UK and Belgium.