Introduction: An overhead line project has been identified which requires a second circuit to be strung to allow for the export of power from the wind farm connections. Planning’s request was for 700mm2 All Aluminium Alloy Conductor (AAAC) operating at 50Deg C giving 1240A pre-fault continuous rating (1470A post fault). Tower analysis revealed that the conductor would overload the towers and would have approx. 50 ground clearance issues requiring towers to be increased in height. This proposal is to cover the development of an alternative conductor to reduce the clearance issues and reduce the loading on the towers without decreasing the rating.

Objectives: The project defined the following objectives:

• Produce conductor systems and testing specifications and procedure for declaration of conformity for conductors operating at 132kV and above to allow tendering process to take place

• Use a consultancy engineering company to advise and carry out study to determine possible currently available conductor options available and provide engineering brief to aid tendering process if a new/novel conductor is required

• Identify through tender process a conductor manufacturer able and willing to develop conductor to suit the Project specific data and loading conditions

• Conductor manufacturer and fittings manufacturer to produce conductor sample, carry out type testing of conductor, associated insulators and fittings to ensure project specification met

• Use a consultancy engineering company to advise and assist with conductor development and to carry out quality control throughout the difference phases of conductor development and testing

• Carry out engineering design checks to determine effect of new conductor on the L3 tower suite to identify and include solutions for: ground clearance issues; tower member strengthening; foundation reinforcement requirements.