P3 Energy Resources Flashcards
What is a renewable energy resource?
A renewable energy resource is one that is being (or can be) replenished as it is used.
What is a non-renewable energy resource?
A non-renewable energy resource will run out at some point in the future.
Where does most of the energy we use come from?
Natural gas. Gas, like oil and coal, is a fossil fuel.
What do fossil fuels contain?
Carbon and hydrogen
What happens inside a power station?
The burning fuel heats water in a boiler producing steam which drives a turbine that turns an electricity generator producing electricity which is then sent to the National Grid.
What are some renewable and non-renewable energy resources?
Renewable
* Geothermal
* Wave
* Tide
* Hydroelectric
* Wind
* Solar
* Biomass
Non-Renewable
* Oil
* Gas
* Coal
* Nuclear
What is a biofuel?
Any fuel taken from living or recently living organisms. Examples are ethanol (from fermented sugar cane) and biodiesel from plants.
What are the benefits of biofuel?
- They are renewable because its biological source either regrows (vegetation) or is continually produced (sewage and rubbish)
- Carbon-neutral - in theory the carbon the living organism takes in from the atmosphere balances the amount released when the biofuel is burnt.
What is nuclear fission and how does it work?
Nuclear fission - the process of splitting a large and unstable nucleus - such as a uranium or plutonium nucleus.
This works because the particles in the nucleus are bound together by a very strong force, if the nucleus can be split energy is released.
What are the advantages and disadvantages of nuclear fission?
Advantages
* Generates more energy than fossil fuels.
* Does not release greenhouse gases into the atmosphere.
Disadvantages
* Generates radioactive waste which is harmful and must be carefully disposed of.
How does wind power work?
Air’s motion is converted to mechanical energy when a turbine connected to an electromagnetic generator generates electricity when wind causes the turbine to spin.
What are some advantages and disadvantages of wind power?
Advantages
* Renewable
* No direct carbon dioxide emissions
Disadvantages
* Intermittent as wind is not always strong enough to turn turbine
* worries about land use, bird disruption and noise
How does wave power work?
1) Water flows into and out of a closed chamber that has an opening below the water compressing and decompressing air. The movement of the air drives a turbine (in a connected chamber) when the air moves back and forwards and the turbine is connected to an electricity generator so electricity is produced.
What are advantages and disadvantages of wave power?
Advantages
* Almost always in motion, even small waves can generate power
* Doesn’t take much space
* Energy available around the clock
Disadvantage
* On very calm days no energy is produced
What are the 2 types of hydroelectric power plants? How do they work?
1) Dams - elevation created by dam gives the water GPE and when the water is released and moves downwards a turbine is spun.
2) Run of river - relies on natural flow of river to drive turbines. This makes it less reliable as it is more variable because it relies on a rivers natural flow.
What are some advantages and disadvantages of hydroelectric power?
Advantages
* Renewable - Earth’s water cycle is constantly renewed by the Sun
Disadvantages
* Major impact on local environment, changes habitats
* Dam collapse can kill those living downstream
* Carbon dioxide emissions during construction and methane released when plants are flooded.
How does tidal power work?
Tidal energy relies on the gravitational pull of the moon which causes the change in water levels known as tides.
A tidal barrage is built across the mouth of a river or estuary where it meets the ocean. The incoming and outgoing tides pass through turbines to generate electricty.
What are some advantages and disadvantages of tidal energy sources?
Advantages
* Predictable supply - there is always tides
* No fuel costs
* Can produce large amounts of electricity
Disadvantages
* Barrages change marine habitats and can harm animals, restrict access and are expensive
* Cannot control supply
* Tides vary on monthly and yearly cycle
How does solar energy work?
Solar PV cells are made from crystals of silicon, when UV light from the sun shines on silicon it releases electrons thereby generating electricity directly.
What are some advantages and disadvantages of solar energy sources?
Advantages
* Cost nothing to run
* Can be added to roofs of houses to generate small amounts of energy
Disadvantages
* Expensive
* Only works in areas with enough sun
* Does not produce electricity when cloudy or at night
* Cannot be used to supply large scale demand
How does geothermal energy work?
It comes from energy released by radioactive substances deep within the Earth. Water is pumped down to rocks heated by this energy to produce steam which drives turbines at ground level.
What are some advantages and disadvantages of geothermal energy?
Advantages
* In some areas ground source heat can be used to heat water in long pipes which is then pumped around buildings
* Low running cost
Disadvantages
* Only available in a few locations on Earth
* Expensive to set up
When does energy demand vary?
At different times of day and by season. Energy generation must match these changes in demand.
What are the power stations with the longest and shortest start-up times?
Longest - Nuclear power stations
Shortest - Natural gas power stations
