Electricity and the National Grid Flashcards
What is the National Grid?
The network of pylons and cables that covers the whole of Britain getting electricity to homes everywhere
Electricity is distributed via the…
National Grid
What does the National grid do? How?
1) Takes electrical energy from power stations to where it’s needed in home and industry.
2) It enables power to be generated anywhere on the grid, and then be supplied anywhere else on the grid
What is the issue with having a high current?
You lose lots of energy through heat in the cables
What do you need in order to transmit a huge amount of power?
either high voltage or a high curr, went
So if high current isn’t good, what happens on the national grid?
It’s much cheaper to boost the voltage up really high (to 400,000 V) and keep the current very low
How to you get the voltage up to 400,000 V to transmit power?
Requires transformers as well as big pylons with huge insulators - still cheaper
What do the transformers do?
They step up the voltage at one end, for efficient transmission, and then bring it down to safe, usable levels at the other end.
The voltage is increased using …
a step-up transformer
The voltage is decreased using …
a step-down transformer
What are the 2 options for transmitting electricity?
Overhead cables or underground cables
Compare the setup costs of Overhead cables and underground cables?
Overhead cables: Lower
Underground cables: Higher
Compare the Maintenance of Overhead cables and underground cables?
Overhead cables: Lots need
Underground cables: Minimal
Compare the Faults of Overhead cables and underground cables?
Overhead cables: easy to access
Underground cables: Hard to access
Compare the ‘looks’ of Overhead cables and underground cables?
Overhead cables: Ugly
Underground cables: Hidden
