Electricity systems and sources

Substations

Substations are electrical installations helping move electricity from where it is generated to where it is needed. They vary in size, which is dependent on the operating voltage, from the largest 400 kV sites which can cover an area of several football pitches to buildings the size of a garden shed down to equipment mounted on wooden poles. Despite the differences in size, substations share similar functions of switching electric circuits and transforming between different voltages.

For most substations the highest electric and magnetic fields are produced by the overhead lines and cables that connect them to the network, rather than from the equipment inside the substation. Where the equipment produces fields which reach outside the perimeter of the substation the fields reduce to a background level within a couple of metres.

 

Types of substations 

The different type of substations that we refer to on this site are: