3.5 Energy Flashcards
Coal (Fossil fuel)
Formed from fossilised plants + a carbon store. Mined from seams of coal found between layers of rock in the earth.
Advantages
- Ready-made
fuel –> cheap to
mine + convert to
electricity
– It lasts
longer than oil or gas.
Disadvantages
- Gives off greenhouse gases when burnt
Oil
- Liquid carbon store formed from fossilised animals
- Lakes of oil are found between seams of rock in the earth.
Advantages
- Ready-made
fuel –> cheap to
extract + convert to
energy - Used in industry and transport
Disadvantages
- Gives off greenhouse gases when burnt
- Non-renewable
Natural gas (Fossil fuels)
Methane and other gases trapped between seams of rock under the earth are released through pipes sunk into the ground.
Advantages
- Ready-made
fuel + relatively cheap - Used in houses for heating + cooking
- Slightly cleaner fuel than coal + oil
Disadvantages
- Gives off greenhouse gases when burnt
- Non-renewable
Nuclear
- Radioactive minerals eg. uranium are mined.
- Electricity is generated from energy released when atoms from these minerals split.
Advantages
- Small amount of radioactive material –> produces a lot of energy
- Relatively cheap to run (once reactor is built) + can last a long time
- Doesn’t give off pollutants
Disadvantages
- Nuclear reactors = expensive to build + waste = highly toxic (leakage = devastating impacts on humans + environments)
Biofuel
- Generated from decaying plant/ animal waste, or organic material + can be burned to provide energy
Advantages
- Cheap + readily available source of energy
- If crops replaced –> long-term + renewable energy source
Disadvantages
- Gives off greenhouse gases when burnt
Solar
- Uses energy from sun
- Harnessed through panels containing solar cells
Advantages
- Clean + renewable form of energy
- No greenhouse gases released during energy production stage
Disadvantages
- Limited in northern countries during winter months
- Dependent of sun shining (not constant energy production)
- Solar farms take up space needed for agriculture, housing etc.
Wind
- Wind turbines spun by power of wind
- Blades of turbine connected to generator, turning kinetic enery into electrical energy
Advantages
- Clean + renewable form of energy
- No greenhouse hases released during production stage
- Can be placed offshore, reducing space needed for wind farms
Disadvantages
- Unattractive, noisy + can harm wildlife
- Wind speed not constant, so production can rise + fall
Wave + Tidal Energy
Tidal - wall placed along shore. movement of water during tides turns turbine (kinetic energy –> electrical energy)
Wave - placing turbines in ocean –> power of waves turns turbines.
Advantages
- Renewable + reliable form of energy (will always be waves + tides)
- No greenhouse gases at energy production stage
Disadvantages
- Tidal plant expensive to construct + limited to places with strong tidal range
Wave - Visual pollution + tech not very advanced yet.
Geothermal energy (what is is, advantages + disadvantages)
- Pipes carrying water through geothermal rocks (underground).
- Steam produced (from pipes or water resrvoirs above geothermal rocks)
- Steam turns turbine –> generating electricity
Advantages
- Renewable + clean energy source
- 24/7 energy production
Disadvantages
- Limited to areas with tectonic plate boundaries
- Geothermal plate boundaries = expensive
- Groundwater can become polluted
Hydro-electric power
- Hydropower uses force of flowing water from dams (built on rivers to hold water in reservoir) to spin turbines
Advantages
- Renewable + clean energy source
- Reliable energy source
Disadvantages
- Dams are expensive to build
- Areas need to be flooded to create reservoirs
- May disrupt river environment + change fish migration patterns (animals may get stuck in turbines)
- May cause political disputs (one country ‘hogging’ water in river flowing through several countries eg. Egypt)
Fuel wood (energy)
- Obtained from felling trees
- Burned to generate heat + light.
Advantages
- Cheap + readily available source of energy
- If trees are replaced –> renewable energy source
Disadvantages
- When burned –> greenhouse gases
- May cause deforestation (Gambia)
Energy security
The balance between energy supply (production) and demand (consumption).
Energy security - Explained
- Countries can have surplus or defecit of energy –> energy traded to even out
- Energy security has led to disputes + conflicts between countries (eg. Nile dam)
- Energy consumption –> also increasing
- Fossil fuels = majority of energy but renewable –> increasing (20% of total)
- Energy consumption increases when coutnries develop + industrialise (due to industry + wealth) + population increases + more teach = more energy
Factors affecting energy supply - Access to tech
Better tech = remote areas can be exploited (eg. North sea + Atlantic)
Easier to extrect natural gas by fracking for example.
Factors affecting energy supply - Physical factors
Fossil fuels only found in some places + Geothermal needs tectonic plate boundaries (geology of area has to be considered)
