National Grid Flashcards
What is the National Grid?
The giant network of transformers and wires that spread across the country to distribute our electricity.
Where does most of the UK’s electricity come from?
Power Stations
How do power stations work?
Power stations work by generating loads of heat, and then converting that thermal energy into electrical energy. How much electricity they create depends on demand.
Generally, demand of electricity peaks in the late afternoon and evening, when everyone gets home from school or work.
To cope with these surges in demand, power stations need to have lots of spare capacity. Therefore, they often run at well below their maximum power output.
When a current flows through a wire, it generates lots of heat due to the resistance in the wire, therefore causing lots of energy to be lost to the surroundings. How do we prevent this?
To avoid energy being wasted, we have to keep the current really low, which means that our **voltage will have to be really high.
This means that once the electricity is generated in the power stations, we have to increase the voltage before sending it across the country. For that, we use step-up transformers. They increase the voltage to around 400,000V.
What is the function of step-down transformers in the National Grid?
They reduce the voltage from roughly 400,000V, to around 230V.
After the energy passes through the step-up transformers, what does the energy have to pass through before reaching the step-down transformers?
Wires and Pylons.
