P3 - Energy Resources Flashcards
How are the planet’s energy demands mostly met?
Burning fossil fuels.
What are the 3 main fossil fuels? What are some of the environmental issues caused by burning fossil fuels?
Coal, Oil, Gas
Issues:
- Greenhouse gases are produced and cause global warming.
- Sulphur dioxide is produced - causing acid rain which destroys wildlife and agriculture.
How are Coal, Oil and Gas formed?
They are the remains of dead animals and plants that have been compressed underground over millions of years.
Where are fossil fuels extracted from? Where are they sent to?
Underground or under the sea bed.
The fossil fuels are then transported to oil refineries and power stations.
How do fossil-fuel power stations produce energy?
1) Burning fuel heats water in a boiler.
2) This produces steam.
3) The steam drives a turbine that turns an electricity generator.
Generator effect - kinetic into electrical
What type of resource are fossil fuels?
A finite/non-renewable resource
What is a non-renewable energy resource?
A resource that can’t be replenished at the same rate that it’s being used.
What is a renewable energy source?
A resource that can be replenished at the same rate that it’s being used.
What are 2 other fuels that power stations can use?
1) Biofuel (methane, ethanol) - renewable
2) Nuclear fuel - non-renewable
What is biofuel? Are biofuels carbon neutral?
Biofuel is a renewable fuel taken from living or dead organic matter.
E.g Animal Waste, Ethanol, Methane
Biofuels are carbon neutral.
What is nuclear fuel? Is it a renewable source?
Nuclear fuel is a fuel that is used to produce energy by nuclear reactions.
E.g uranium or plutonium
It’s a non-renewable resource
How does a nuclear power station work?
1) Uranium fuel sealed in cans in the reactor core.
2) Unstable nuclei of uranium split in two and energy is transferred.
3) A coolant is pumped through the core and transfers the energy.
4) This energy - transferred by the coolant - is used to turn water into steam.
5) The steam drives a turbine and this turns an electricity generator.
How does the amount of energy produced by fossil fuels compare to the amount of energy produced by nuclear fuel?
Nuclear fuel produces 10,000x more energy per kg of fuel.
What is the problem with using nuclear power?
The uranium and plutonium fuel is a limited resource - its non-renewable.
Radioactive waste is produced that has to be stored for years due to the long half-life of uranium and plutonium.
How does wind power work? What are the disadvantages?
1) The force of the wind drives the turbine’s blades around.
2) This turns a generator.
Higher wind speeds = more power generated.
Disadvantages:
- Wind power can be unreliable if there is little or no wind.
- Eye sore
How does wave power work? What are the disadvantages?
1) Motion of the waves make a floating generator move up or down.
2) A cable between the generator and the shoreline delivers the electricity to the grid system.
Disadvantages:
- Spoils coastline areas with cables and buildings.
- Habitats of marine life and birds may be affected.
How does hydroelectric power work? What is the main disadvantage?
1) Rainwater is collected in a reservoir.
2 The rainwater flows downhill through turbines that drive electricity generators.
Disadvantage:
-Large reservoirs of water needed.
How does tidal power work? What are the disadvantages?
1) Water from each high tide is trapped behind a barrage.
2) The water is released back into the sea through turbines which turn generators.
Disadvantages:
- Can change tidal patterns.
- Affects habitats.
How does the sun transfer energy?
Solar radiation (infrared).
When might it be appropriate to use solar panels? What are the advantages and disadvantages?
Can be used when only small amounts of energy are needed.
✅ Cost nothing to run.
❌ -Expensive to install. -Need large areas of land for grid-level energy.
How do solar heating panels work?
Solar heating panels work to heat the water flowing through it.
This can supply plenty of hot water to a house on a sunny day.
How does a solar power tower work?
1) Thousands of flat mirrors (controlled by computers that track the sun) reflect sunlight on to a big water tank at the top of a tower.
2) The water in the tank is heated and turns to steam.
3) The steam is piped down to ground level where it turns electricity generators.
What causes geothermal energy?
Energy is released by radioactive substances deep within the earth and heats the surrounding rocks.
How do geothermal power stations work?
1) Cold water is pumped deep down to hot rocks in volcanic areas to produce steam.
2) The steam drives a turbine and this turns a generator.
What does ‘carbon neutral’ mean?
The carbon taken in by living organisms (CO2), is equal to the carbon released when fuels are burnt.
What is the main problem with renewable energy?
Renewable energy is currently not able to meet the world’s demand for energy.
How does energy supply and demand impacts the way power stations work?
Electricity generators need to match the varying demands for energy.
E.g Time of year impacts how much energy is needed each day - e.g in winter heating increases.
