SU5610 : 400 KV Line Refurbishment, Mayles Lane
taken 12 years ago, near to Wickham, Hampshire, England
In summer 2012 National Grid Plc were refurbishing the 400 KV overhead lines between Fawley (power station) and Lovedean (main grid substation). The work was being carried out by an alliance between National Grid and Babcock, AMEC and Mott McDonald.
A NOTICE OF WORKS posted in January 2012 said that "as this is a major project, the works will comprise all or some elements of the following:- technological and ecological surveys, replacing overhead line conductors (known as "reconductoring"), replacing ageing insulators, replacing certain sections of steelwork on the towers, inspecting and repairing concrete foundations."
The old conductors were made of aluminium with steel wrapped around it. There were four wires per phase, in a square configuration, each of 400 sq.mm. cross-sectional area. The new conductors were of type AAAC, which is made of two different alloys of aluminium, the inside for easy conduction and the outside for strength. There were three wires per phase, in a triangular configuration, each of 700 sq.mm. cross-sectional area.
The earth wire, which runs along the top of the pylons, was also renewed with a smaller one having fibre optics wound around it.