National Grid

What is the National Grid?

A system of power stations, cables, and transformers that distributes electricity across the UK from where it's generated to where it's used.

What is a step-up transformer and why is it used?

A transformer that increases voltage and reduces current before long-distance transmission. This reduces energy lost as heat in cables (P = I²R).

What are transmission cables and why are they important?

High-voltage cables that carry electricity long distances. High voltage = low current → reduces energy loss.

What is a step-down transformer and why is it used?

A transformer that reduces voltage to a safe level (230 V in homes) before electricity reaches consumers.

Why is electricity transmitted at high voltage?

High voltage reduces current, which reduces energy lost as heat in cables (because energy loss = I²R).

What is the sequence of electricity from power station to home?

Power station → Step-up transformer → Transmission cables → Step-down transformer → Homes/buildings.