National Grid

• What is the national grid?

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

  From power stations
• How do power stations generate electricity?

  By converting thermal energy into electrical 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?

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

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

  It generates lots of heat due to resistance
• How do we minimize energy loss during transmission?

  By keeping the current low and voltage high
• What do step-up transformers do?

  Increase the voltage to around 400,000 volts
• What happens to the voltage before electricity reaches its destination?

  It is reduced by step-down transformers
• What voltage is electricity reduced to before use in homes?

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

  High voltages are dangerous and can damage appliances
• What components make up the national grid?

  • Transformers
  • Wires
  • Pylons
• How does the national grid minimize energy loss during electricity transmission?

  • Uses step-up transformers to increase voltage
  • Transmits electricity at high voltage and low current
  • Uses step-down transformers to reduce voltage for safety
• What is the main purpose of the national grid?

  • Distribute electricity across the country
  • Ensure a stable supply of electricity
  • Manage electricity demand and generation