This is GCSE revision for Physics Unit 1.
The National Grid in the UK is a system of TRANSFORMERS, PYLONS and TRANSMISSION LINES that transports electricity from the power stations to houses and other buildings. (For GCSE, it is important to remember that the National Grid does not include the power stations themselves!)
To transport the electricity, the voltage is ‘stepped up’ before travelling along the transmission lines by a STEP-UP TRANSFORMER. By increasing the voltage, the grid reduces the current flowing through the wires. By decreasing the current, you reduce the heat produced along the wires, therefore reducing the amount of energy wasted as thermal energy, making the network more energy efficient.*
*This bit is important and needs learning, as not only do you need to state what the national grid does, but why!
Test Your Knowledge – Try these few questions!
- What is the National Grid made up of? (3 marks)
- The voltage in the transmission lines is increased. How? (2 mark)
- The voltage in the transmission lines is increased. Why? (3 marks)
- What type of energy does the National Grid transport?
- The National Grid is not 100% efficient. What type of energy does it lose most and how? (4 marks)
Links: Transformers (P3), Energy Efficiency (P1), Underground and overhead cabling (P1)
PS – The (P#) above are references to which Unit the topics come under for GCSE Science.