3.5 - Energy Flashcards
Reasons for an increase in energy demand (name 2)
- Higher demand for food leads to more intensive farming which requires more energy for machines, light and heat
- Increasing industry requires energy for heating, lighting and machinery
- There is more transport all of which requires energy in the form of petrol, diesel or electricity
- Urbanisation increases with development increasing domestic appliances, heating, lighting
- Increased wealth means people buy more appliances and technology which require energy
Non-renewable energy
Finite or non-sustainable source of energy (e.g. fossil fuels, oil)
Renewable energy
A resource that can be used continually without running out (e.g. wind power, hydro-electric power)
Natural gas
Flammable gas consisting largely of methane and other hydrocarbons, occuring naturally underground and used as fuel.
Sustainable
Causing little or no damage to the environment and therefore able to continue for a long time.
Advantages of coal (name 2)
- World reserves estimated to be 120 years
- Reliable and easy to produce energy from
- Technology has enabled coal to be obtained more easily
Disadvantages of coal (name 2)
- Non-renewable - it will run out
- Releases carbon dioxide (greenhouse gas) and sulphur dioxide (causes acid rain) when burnt
- Heavy and bulky to transport
- Most accessible coal has been used and so the cost of production has increased as coal reserves are more difficult to access
- Risk of accidents due to mine collapse and gas release
- Opencast mining damages large areas of the environment
Advantages of oil and gas (name 2)
- Reliable and easy to produce energy from
- Efficient - it has a high energy density so produces a lot of energy per kilogram
- Not as harmful to the environment as coal (gas is the least harmful)
- Easy to transport via pipeline
Disadvantages of oil and gas (name 2)
- World reserves estimated to be between 50-60 years
- Non-renewable - they will run out
- The gases released when they are burnt are greenhouse gases
- Oil spills damage the environment and wildlife over large areas
- Prices fluctuate rapidly
- Supplies can be affected by conflict and political disagreements e.g. the war in Ukraine
Wind energy advantages (name 2)
- No air or water pollution
- Free source of energy
- Wind farms are relatively inexpensive
- The land of the wind farms can be used for other purposes
Wind energy disadvantages (name 2)
- Requires constant and significant amount of air
- Requires significant amount of space
- Have visual impacts on landscapes
Solar energy advantages (name 2)
- Infinite source of energy supply
- No air and water pollution
Solar energy disadvantages (name 2)
- Manufacture and implementation can be expensive
- Storage and back up is mandatory
- Workability depends on the availability of sun light
Hydro power advantages (name 2)
- Sources are abundant, clear and safe
- No standby losses
- Relatively inexpensive
Hydro power disadvantages (name 2)
- Large areas of land are flooded behind the dam
- Dam traps sediment which can affect ecosystems downstream
- The installation of hydropower plants can be time-consuming and disruptive for people who live nearby.
- Dams can irreversibly alter the habitats of water-dwelling species, and kill off members of those species at an alarming rate.
- Visual pollution
- Can prevent fish movement upstream
- Expensive to build and maintain