Energy Flashcards
What are all the energy stores (8)
Chemical, kinetic, gravitational, elastic, thermal, magnetic, electrostatic, nuclear
What are all the energy transfers (4)
Mechanically, electrically, by heating, by radiation (light and sound)
What is the equation for efficiency
Useful energy output / total energy input (x100% if you need it in a percentage)
What is the principle of conservation of energy
Energy cannot be created or destroyed, only transferred from one form to another, therefore the total energy in a system always remains constant
What are Sankey diagrams
Shows the flow of energy, with the total input as an arrow on the left going to right, with the useful output continuing right whereas the wasted output goes down. The width of the arrows shows us the percentage of the total energy that it accounts for. (See google for better representation)
What is the energy transfer for wind power
Kinetic energy is mechanically transferred into electrical energy
What is the energy transfer for hydroelectric power
GPE is turned into kinetic energy naturally as the water falls, which mechanically turns the engine to make electric energy
What is required for mechanical energy transfer
A machine or device facilitating the conversion
What is the energy transfer for geothermal energy
Thermal energy is transferred into kinetic energy as steam is released from the earth, which mechanically turns a turbine, which generates electrical energy
What is the energy transfer for solar pannels
Light energy from sunlight is converted through radiation into electrical energy in solar cells
What is the energy transfer for solar heating systems
Thermal energy from sunlight is converted into heat energy via radiation
What is the energy transfer for fossil fuels
Chemical energy is turned into kinetic energy by heating, as steam, which mechanically turns a turbine to become electrical energy
What is the energy transfer for nuclear power
Nuclear energy is transferred into thermal energy via heating, which then becomes kinetic energy as steam, which mechanically turns a turbine, which generates electrical energy
Why is steam used to push turbines in electricity generation
The thermal energy produced is used to boil water, to turn it into steam which expands and pushes the turbine as it rises.
What is the unit for energy
Joules (J)
What is the unit for acceleration
m/s^2
Metres per second per second
What are the advantages and disadvantages of oil
+ It is reliable
+ it is quick to create electricity when burned
+ a little oil creates a lot of energy
+ it is abundant
- it pollutes
- it is non-renewable so will run out
What are the advantages and disadvantages of coal
+ it is very cheap
+ there is a large supply
+ it is easy to store
- it is non-renewable so will eventually run out
- very polluting (CO2)
What are the advantages and disadvantages of natural gas
+ it is very cheap (cheapest fossil fuel)
+ it is very reliable
+ it is quick to generate electricity
+ it is around 93% efficient
- it is very flammable so is a fire hazard
- it is expensive to store
What are the advantages and disadvantages of nuclear fission
+ it is non-carbon emitting
+ the resources are abundant and cheap
+ it does not take up a lot of space
- emits radiation
- nuclear accidents are possible and can be very dangerous
- the plants are expensive to build
- it is NON-renewable
- it takes a long time to turn the power station off
What are the advantages and disadvantages of biomass
+ reduces waste (uses organic matter e.g. trees, plants, food waste etc.)
+ it is renewable
+ replanting the burned trees can make the process carbon neutral
- it is expensive to set up and maintain
- harmful gases are produced when burning
What are the advantages and disadvantages of geothermal energy
+ it is cheap to access and run once the plant is set up
+ it is not reliant on the weather
- it needs to be above a tectonic plate boundary or hotspots
- it can cause earthquakes
- it is expensive to set up
What are the advantages and disadvantages of solar energy
+ it is renewable so will never run out
+ it can easily be set up on any scale
+ very low maintenance
+ can be stored in batteries
+ lots of solar energy available in summer
- takes up quite a lot of space
- high installation cost
- less solar energy is available at night and in winter
- the batteries are expensive
What are the advantages and disadvantages of wind power
+ it is renewable so will never run out
+ it is very low maintenance
+ the UK has a lot of appropriate locations
- it is expensive to install and repair
- it only works 75% of the time
- it is not always windy
- requires windy locations
What are the advantages and disadvantages of hydro-electricity
+ it is renewable so will never run out
+ it is east and fast producing
+ easy to turn off or on
+ does not create any atmospheric pollution
- there are not many suitable locations
- it is very expensive to build
- many people are displaced due to rising/falling water levels
- has negative impacts on the local environment
