Flick a switch and your lights turn on, but for those who have wondered how electricity gets to you, here’s a step-by-step guide that traces the generation, transmission and distribution of electricity to your home.
Electricity is generated in power stations (1).
This electrical current is then transported from power stations to customers via a network of powerlines and cables. This network is made up of a transmission network and a distribution network.
The transmission network transports bulk power across long distances at high voltages. As it leaves the power station, electricity is passed through a transformer in the switchyard (2) which converts it to a very high voltage (up to 330,000 volts). This gives the electricity enough force to travel along the transmission lines (3) to 'terminal' and 'zone' substations in or near population centres. These substations use step-down transformers to convert the electricity to a lower voltage (33,000 volts or less), suitable for distribution around towns and suburbs.
The distribution network delivers electricity from zone substations to customers, over shorter distances and at lower voltages.
'Feeder' lines (5) pass electricity from the zone substation to small distribution substations, where the electricity is converted to even lower voltages. Your local distribution substation (6) may be a pole-mounted transformer or a kiosk on the verge. From here, electricity travels along low voltage lines (240 volts) to the customer's point of supply (7). This point of supply may attached to the building (if you have overhead power), or a pillar just inside the boundary (underground power).
Page update on 26 September 2007
