Renewable Energy (Cambridge (CIE) O Level Geography)

Hydroelectric

• No greenhouse gas emissions

• Controls flooding downstream

• Often in sparsely populated areas

• May provide water storage for irrigation and domestic use

• Large areas of land are flooded behind the dam

• Dam traps 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

• No greenhouse gas emissions

• No air pollution

• Has the potential to produce large amounts of energy

• Reliable

• Expensive to build and maintain

• Can affect marine ecosystems

• Few suitable sites

Wind

• No greenhouse gas emissions

• No air pollution

• Can be small or large scale 

• Cheap to run

• Can be on land or offshore

• 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

• 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

• Expensive to install

• Not reliable, only works when it is sunny

• Large numbers needed to produce energy

• Uses large areas of land

Geothermal

• No CO₂ gases

• Lots of potential sites

• Reliable 

• Can produce large amounts of energy

• Expensive

• Emits sulphuric gases

• High temperatures cause maintenance issues

Biomass/Waste

• Uses waste or biofuels which regrow

• Available in most locations

• Air pollution

• Produces greenhouse gases

• Expensive