Green transformation

EDF Energy Networks has switched on what it believes to be the world’s first purpose-built transformer filled with vegetable oil.

The transformer, which reduces the voltage from 132,000V from overhead lines to 33,000V, is based in a substation in north Luton, and plays an essential role in the transmission of electricity to homes and businesses in the town.

The Envirotemp FR3 liquid, made from edible soya beans, is being used to replace mineral oil in the transformer. About 30,000 litres of oil are needed to act as a coolant and insulator between the metal tank and the electrical equipment inside.

This is the first time that vegetable oil has been used at such a high voltage in the UK and it is the first purpose-built 132,000V transformer in the world to be energised, although there have been some mineral oil transformers that have been retrospectively filled with vegetable oil.

The liquid is an environmentally-friendly alternative to depleting mineral oils. It is made from a natural, renewable resource, is biodegradable and more fire resistant. It is also expected to extend the life of the transformer.