Generating Electricity Flashcards
How does a fossil fuel generator work?
1) The fossil fuel is burned to convert the chemical energy into thermal energy.
2) The heat energy turns water into stream.
3) The steam turns a turbine.
What is the difference between a nuclear generator and a fossil fuel generator?
Nuclear generators use nuclear fission from uranium or plutonium instead of burning fossil fuels.
What is an issue with building nuclear power stations?
They take the longest time of any electricity option to set up.
How do you generate electricity from wind?
You put windmills in windy areas like moors and coasts. The wind turns the windmill which turns the turbine inside.
What are two advantages of wind power?
- No atmospheric pollution
* No permanent damage o environment
What are four disadvantages of wind power?
- Visual pollution
- Noise pollution
- No wind = no power
- Low amount of power from each turbine
Where do solar cells get their electric currents from?
The Sun’s radiation
What are two advantages of using solar cells?
- No environmental damage after fabrication
- Can be very reliable in some countries
- In Britain they can power individual homes easily
What are two disadvantages of solar cells?
- Difficult to connect to the National Grid
- Start up cost huge compared to value of electricity generated
- Relies on sunlight
How does hydroelectric power work?
1) A valley is flooded by building a big dam.
2) Rainwater is caught by the dam.
3) Water is forced past turbines.
What are three advantages of hydroelectric power?
- No atmospheric pollution
- No problem with reliability
- Useful for small scale, remote projects
What are four disadvantages of hydroelectricity?
- Huge impact on habitats and area
- Unsightly
- High initial cost
- Difficult to connect to the National Grid
What is pumped storage?
“Spare” nighttime electricity is used to pump water up to a higher reservoir. This can then be released quickly during peak times.
Why does pumped storage work so well?
Because at night electricity demand is low so the electricity doesn’t go to waste.
What are tidal barrages?
Big dams built across estuaries with turbines in them. The movement of the tides turns the turbines.
What are three advantages of tidal barrages?
- No atmospheric pollution
- There are always going to be tides
- Can store energy for peak times
What are three disadvantages of tidal barrages?
- Prevent access to estuary
- Tides are variable
- High initial cost
How can sea waves produce electricity?
Lots of small wave powered turbines are placed on the coast. As waves come in they provide an up and down motion which can force air past a generator.
What are two advantages of using sea waves to generate electricity?
- No atmospheric pollution
* Cheap to run
What are three disadvantages of using waves to generate electricity?
- Visual pollution
- Unreliable
- High initial cost
What is geothermal energy?
When steam and water rise from the ground and turn a turbine.
Where do geothermal power stations need to be built?
In areas where hot rocks are close to the surface.
What is an advantage of geothermal energy?
The source is free.
What is a disadvantage of geothermal energy?
The power station required is very expensive.
What are biofuels?
They are renewable sources from plants and waste.
Why are biofuels better than fossil fuels?
Because they are carbon neutral.
In the UK, where do a majority of our energy come from?
Non-renewable sources.
What are three problems of using non-renewable sources for electricity?
- Releases harmful gases like carbon dioxide and sulphur dioxide.
- Damages landscape due to huge mining pits and oil spills.
What is a problem with the waste from nuclear power?
It is dangerous and difficult to dispose of.
What are two problems with biofuels?
- Methane released when burned.
* Deforestation to make way for biofuel production.
What is CCS?
Carbon Capture and Storage aims to reduce the amount of Carbon Dioxide in the atmosphere by piping emissions into empty gas/oil fields underground.
What should be considered when planning a new power station?
- How much it costs to set-up and run.
- How long it takes to build.
- How much power it can generate.
- Decommissioning time
- Reliability
Why is gas replacing oil and coal power stations?
Because it has the shortest start up time and we have the most of it.
What is the best location for solar panels?
Somewhere sunny
What is the best location for natural gas stations?
Anywhere there’s piper gas.
What is the best location for hydroelectricity?
Hilly, rainy places with floodable valleys.
What is the best location for wind turbines?
Exposed, windy places.
What is the best location for oil plants?
Near the coast because oil is transported by sea.
What is the best location for wave power?
On the coast
What is the best location for a nuclear power station?
Away from people and close to a reliable water source.
What is the best location for tidal barrages?
Big river estuaries.
What is the best location for geothermal plants?
Volcanic areas
What will the National Grid need to do if demand increases?
Build more power stations and/or increase its power output.
How can demand on electricity be reduced?
By consumers buying energy-efficient appliances.
What does the National Grid do?
It takes electricity from power stations to where it is needed.
What are the ideals conditions to transport electricity?
A high voltage or a high current.
Does the National Grid raise the voltage or the current? Why?
The voltage because it’s cheaper as less energy is lost as heat that way.
What is the voltage of electricity in the National Grid?
400,000 volts
What do transformers do in the National Grid?
Step up the voltage at the power stations for efficient transmission and step down the voltage at the other end to make the electricity useful and safe.
Do overhead or underground cables have better thermal/electrical insulation?
Overhead because the air acts as an insulator whereas insulation must be artificially produced below ground.
Do overhead or underground cables have easier installation?
Overhead as they are a lot easier and cheaper to get to.
Are overhead or underground cables easier to maintain?
Underground as they very rarely get damaged.
Do overhead or underground cables carry more of a risk?
Overhead as they are openly exposed.
Do overhead or underground cables create more disturbance?
Underground
Do overhead or underground cables have more of a visual impact?
Overhead
Why can’t underground cables be placed in some areas?
Land restrictions
