Good as new

National Grid has placed a £1 million order with ABB to refurbish a shunt reactor that was installed at Willesden substation in London in 1967.
The project is being funded under the Network Innovation Allowance (NIA) provided through Ofgem. It aims to demonstrate that refurbishment is an economically viable methodology for upgrading service-expired 13 kV (kilovolt) shunt reactors to modern standards of performance and energy efficiency.

The new RIIO (revenue = incentives + innovation + outputs) funding framework means that National Grid is keen to explore the relative merits of refurbishment and replacement of key assets such as shunt reactors, which improve the efficiency of the transmission and distribution network.
Recent innovations in materials science mean that modern transformers are built with steel that has lower losses than a 40-year old design. As such a refurbishment based on the old design would not meet today’s high specifications for transmission equipment.
ABB will transport the 13 kV 2 x 30 MVA (megavolt ampere) shunt reactor to its transformer centre of excellence in Drammen, Norway, where a detailed inspection and appraisal will establish options for redesign and remanufacture of a new active part, as well as refurbishment of the tank and cooler bank. The refurbished unit will then be subjected to factory acceptance testing (FAT) to the very latest standards before being returned to Willesden 275 kV substation for installation and commissioning on its original plinth, saving extensive civil works.
“The Willesden project is a very significant breakthrough for ABB’s Transformer Service team in the UK that enables us to deliver a practical real-world demonstration of how a non-ABB shunt reactor asset over 40 years old can be remanufactured cost effectively in its existing tank, while upgrading it with state of the art design and materials” says Matthew Pownall, Divisional Manager ABB Power Products Service UK.

National Grid has a fleet of around 70 shunt reactors in the UK