DONG Energy are constructing an extension to the Burbo Bank Offshore Wind Farm which will have a capacity of approximately 260MW. Kelvin Power Consultants have been employed by Dong Energy to provide technical design services for the 11km onshore 220kV export cable from landfall to the onshore substation.

The onshore cable route comprises of a 220kV 11km cable route. The route includes several challenging Horizontal Directional Drill (HDD) crossings under existing infrastructure for which Kelvin Power Consultants undertook the following:

• Assessment of ground conditions to establish HDD constraints
• Scope and management of additional ground investigation
• Design of the proposed HDD profiles for the 600m landfall HDD and separate 700m onshore HDD
• Duct pull in force, cable pull in force and structural calculations
• Liaison with Network Rail and obtaining necessary technical approvals
• Liaison with Natural Resources Wales, Welsh Water, North Wales Trunk Road Agency and Local Highway Authority.
• Management of specialist earthing designs and calculations
• Management and supervision of onsite trial pits to determine service locations
• Cable route setting out and services clearance in advance of fencing works