National Grid

• What is the national grid?

  A giant network of transformers and wires
• From where is electricity in the UK primarily generated?

  From a range of different sources, mainly power stations
• How do power stations generate electricity?

  By generating heat and converting thermal energy
• What factors influence how much electricity power stations generate?

  Electricity demand
• When does electricity demand generally peak?

  In the late afternoon and evening
• Why do power stations need spare capacity?

  To cope with surges in demand
• What happens to power stations' output during low demand times?

  They often run at below maximum power output
• What is the equation for power?

  Power = Voltage × Current
• What is the problem with high current flowing through wires?

  It generates lots of heat due to resistance
• What do we use to increase voltage before transmission?

  Step up transformers
• How do we minimize energy loss during electricity transmission?

  By keeping the current low and voltage high
• What voltage do step up transformers increase electricity to?

  Around 400,000 volts
• How is electricity transmitted across the country?

  Through wires between huge pylons
• What happens to the voltage before electricity reaches its destination?

  It is reduced by step down transformers
• What voltage do step down transformers lower electricity to?

  Around 230 volts
• Why is it important to lower the voltage before use?

  High voltages are dangerous and can damage appliances
• What is the process of electricity distribution in the national grid?

  • Electricity generated in power stations
  • Step up transformers increase voltage to 400,000 volts
  • Electricity transmitted through wires and pylons
  • Step down transformers reduce voltage to 230 volts
  • Safe for use in homes
• What should viewers do if they found the video useful?

  Give a like and subscribe