National Grid

• What is the national grid?

  A system of cables and transformers linking power stations to consumers across the UK
• What are transformers?

  These change the potential difference
• What are step-up transformers?

  Increase the pd from the power station to the national grid. So as the power is constant (P=IV) current decreases so less energy is lost
• What are step-down transformers?

  Decrease the pd from the national grid to consumers for consumer safety