Albert Teen
Electricity

YOU ARE LEARNING:

Mains Electricity

# Mains Electricity

### Mains Electricity

The mains electricity is an AC supply. In the UK, the domestic electricity supply has a frequency of 50 Hz and is about 230 V.

What is mains electricity?

Do you think mains electricity is alternating current (AC) or direct current (DC)?

AC constantly changes direction. If the AC of mains electricity changes direction 50 times per second, what is the frequency of mains electricity?

In the U.K., the mains electricity is supplied to homes by power stations as AC that has a frequency of 50 Hertz. That means that the electricity changes direction 50 times per second.

What do we actually mean when we talk about the voltage of an electrical supply?

Which of these do you think is a realistic voltage for mains electricity?

We use mains electricity to power everything in our homes. In the U.K. it has a voltage of 230 V.

If we transport electricity a long way, is it better to have a high or low voltage?

Why is mains electricity supplied as AC rather than DC?

Mains electricity is transported from power stations to our homes over hundreds of miles, so it needs to travel with a high voltage. If we used a DC, we would lose a lot of energy as heat through the resistance in the cables. So instead, we transport the electricity as an AC with a high voltage and low current to reduce this heat loss.