Transmitting Electricity

Have you ever thought about how electricity actually gets to our homes, schools and places of work? Well, there’s some seriously cool technology that’s used.

Electricity is generated in power stations that burn carbon fuels or use nuclear fuels to create steam that drive turbines – basically a rotating shaft with blades. Then powerful electromagnets create the electricity. The energy has changed from chemical energy to kinetic and mechanical energy in the turbine, to electrical energy.

The movement of the sails is kinetic energy, so essentially it’s fast tracking the energy to the point where it’s ready to be turned into electricity with electromagnetism.

Once the electricity has been created, it needs to be moved to where it’s needed, and this step is known as transmission.

There’s a national grid of pylons connecting over 7,000 kilometres of overhead lines, and also 600 kilometres of underground cables, to take the electricity where it needs to go… but the electricity isn’t quite ready to set off.

The electricity just needs to be increased in voltage. Most electricity is generated at 22,000 volts. It’s increased to as much as 400,000 volts to help it travel more efficiently over long distances.

This is done through things called transformers (no, not Optimus Prime). You might have seen strange looking electrical yards with lots of machinery around your town or on the edges of motorways. These are substations. They’re junction points where transformers change the voltage and direction of the electricity. They increase the voltage to move electricity around the country and decrease it again when it’s close to its destination, so that it’s safe to be used. After all, 400,000 Volts is over one and a half thousands times more power than we use in our homes.

At the substations, electricity is reduced in power, with different customers taking supply at the right voltage for them. Large industrial companies might take it direct from substations at 33,000 volts, whilst smaller industrial customers, towns and villages will take it at 11,000 volts. It’s finally reduced all the way down to 240 volts for use in our homes, schools and shops.

Generating, transmitting and distributing electricity are just three steps in the process – each done by very different companies. Then there are a large number of supply companies who actually sell the electricity to homeowners, shops and offices – and raise the monthly bills.

The important thing is that supply is always there when needed. Energy generators, transmitters, distributors and suppliers are always working together to find smarter ways to make sure there’s enough to go around – from sharing electricity with other countries to encouraging people to use more energy efficient equipment and to use electricity at different times of the day. After all, you don’t need to charge a car or wash your clothes during the day – you can do it at night when there’s less overall demand.

A Transmission Network Control Centre monitors the grid 24/7 to make sure electricity is moved around the network safely and gets to where it’s needed. And if an alarm does ring, it can respond at any time of the day to resolve any issues and make sure supply is restored. And make sure that our gadgets and appliances work where and when we want them!