P1.3 - Mains Electricity Flashcards
What is the sequence of how most electricity generated?
1) Burning fuel
2) Heats water -> steam
3) High pressure steam -> drives turbine
4) Turbine -> turns generator
5) Generator -> electricity
Describe the energy changes in generating mains electricity
Chemical -> heat (burning fuel)
Heat -> kinetic (steam)
Kinetic -> electrical (generator)
Name the 4 main ways of generating power that turn a turbine directly
Wind
Waves
Tidal
Hydroelectric
How does geothermal energy work?
Passes water over hot underground rocks
-> steam -> turbines
Which form of generating power creates electricity directly from sunlight?
Solar panels
Which 2 fuels are most electricity generated from?
What are the main problems with these fuels?
Fossil fuels:
Fossil fuels -> CO2 -> climate change
Nuclear power:
Nuclear power -> radioactive waste (but no CO2)
What is the main advantage and disadvantage of wind, water and solar power?
Ad: Renewable
Dis: Low energy density
What are the 2 main problems with renewable sources?
Not reliable
Damage habitats
What is the national grid?
Wire network carrying electricity across country
How is energy wasted through the National Grid?
As heat when electio current flows through wires
Where are step up transformers, what do they do, and why?
At powerstation
Increase voltage and decrease current
Save energy over long distances
Where are step down transformers, what do they do, and why?
Closer to houses
Reduce voltage, increase current
To get to safer voltage in houses
