Renewable Energy (Cambridge (CIE) IGCSE Geography)

Importance of Renewable Energy Sources

• Renewable energy sources are infinite and will not run out. They include:

  • hydroelectric

  • wave/tidal

  • wind

  • solar

  • geothermal

  • biomass/waste

• Once in place, except for biomass/waste, they do not produce any greenhouse gas emissions

• Greenhouse gases may be emitted in the production, construction and transport of the equipment

Increase in renewable energy

• Renewable energy is increasingly important in the global energy mix

• This is due to:

  • Non-renewable fossil fuels will at some point run out and so they need to be replaced with another energy source

  • The use of non-renewable fuels is damaging to the environment.

    • Fossil fuels, when burnt, release greenhouse gases and the sulphur dioxide released causes acid rain

    • Mining and drilling for fossil fuels can destroy habitats and damage the surrounding environment

  • Increasing awareness of the impact of using fossil fuels has resulted in international pressure to reduce their use

  • Countries wanting to reduce their reliance on imports of energy sources and improve their energy security

Advantages and disadvantages of renewable energy sources

Hydroelectric energy

Advantages

• No greenhouse gas emissions

• Controls flooding downstream

• Often in sparsely populated areas

• May provide water storage for irrigation and domestic use

Disadvantages

• Large areas of land are flooded behind the dam

• Dams trap sediment, which can affect ecosystems downstream

• Visual pollution

• Can prevent fish movement upstream

• People and settlements may have to be relocated

• Expensive to build and maintain

Wave/tidal

Advantages

• No greenhouse gas emissions

• No air pollution

• Has the potential to produce large amounts of energy

• Reliable

Disadvantages

• Expensive to build and maintain

• Can affect marine ecosystems

• Few suitable sites

Wind

Advantages

• No greenhouse gas emissions

• No air pollution

• Can be small or large scale 

• Cheap to run

• Can be on land or offshore

Disadvantages

• Not reliable only works when the wind is strong enough but not too strong

• Visual pollution

• Noise pollution 

• Many turbines (233) are needed to produce the same energy as an average coal-fired power station

• May affect bird migration patterns or kill birds who fly into the moving blades

Solar

Advantages

• No greenhouse gas emissions 

• No air pollution

• Can be small or large scale 

• Can be used in most locations

• Can be incorporated into building design

• Technology is improving and reducing cost

Disadvantages

• Expensive to install

• Not reliable; only works when it is sunny

• Large numbers needed to produce energy

• Uses large areas of land

Geothermal

Advantages

• A reliable source of energy

• Lower greenhouse gas emissions

• Produces hot water as well as electricity

Disadvantages

• Expensive

• Emits sulphuric gases

• High temperatures cause maintenance issues

Biomass/waste

Advantages

• Uses waste or biofuels that regrow

• Available in most locations

Disadvantages

• Air pollution

• Produces greenhouse gases

• Expensive