Renewable resources are replenished either by:
A non-renewable energy resource is one with a finite amount. It will eventually run out when all reserves have been used up.
The table below shows the main features of the most common energy resources used today.
|Energy resource||Energy store||Renewable or non-renewable||Uses||Power output||Impact on environment|
|Fossil fuels (oil, coal and natural gases)||Chemical||Non-renewable||Transport, heating, electricity generation||High||Releases CO2 (causes global warming)|
|Nuclear fuels||Nuclear||Non-renewable||Electricity generation||Very high||Radioactive waste (needs to be disposed of safely)|
|Biofuel||Chemical||Renewable||Transport, heating, electricity generation||Medium||'Carbon neutral' - little or no effect on the environment. Although growing biofuels can take up land that could be used for farming.|
|Wind||Kinetic||Renewable||Electricity generation||Very low||Takes up large areas that could be used for farming. Windmills change the landscape|
|Hydroelectricity||Gravitational potential||Renewable||Electricity generation||Medium||Local habitats are affected by the large areas that need to be flooded to build dams|
|Geothermal||Internal (thermal)||Renewable||Electricity generation, heating||Medium||Very low|
|Tides||Kinetic||Renewable||Electricity generation||Potentially very high, but hard to harness||Tidal barrages can block sewage which needs to go out to sea. Local habitats also affected|
|Sun||Nuclear||Renewable||Electricity generation, heating||Dependent on the weather and only available during daylight||Very little|
|Water waves||Kinetic||Renewable||Electricity generation||Low||Very low|