Energy resources
There are different Useful supply or store of energy. in the world and the amount of The capacity of a system to do work or the quantity required for mechanical work to take place. Measured in joules (J). For example, a man transfers 100 J of energy when moving a wheelbarrow. stored by them varies greatly. For example, the amount of nuclear energy stored within 1kg of uranium is enormous, but the The energy stored by an object lifted up against the force of gravity. Also known as GPE. stored by many thousands of tonnes of water held back by a dam is less.
Renewable or non-renewable
Renewable resources are replenished either by:
- human action - eg trees cut down for biofuel are replaced by planting new trees
- natural processes - eg water let through a dam for Electricity that is generated by the movement of water. is replaced through the The continuous movement of water on, above and below the Earth.
A non-renewable energy resource is one that is not being replenished as it is being used. It will eventually run out when all reserves have been used up.
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Different energy sources
The table below shows the main features of the most common energy resources used today.
| Energy | 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 so low impact |
| Wind | Kinetic | Renewable | Electricity generation | Very low | Take up large areas that could be used for farming, people say windmills spoil their view |
| 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 | 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 |
| Sun | Nuclear | Renewable | Electricity generation | Potentially very high, but hard to harness | Very little |
| Water waves | Kinetic | Renewable | Electricity generation | Low | Very low |
| Energy | Fossil fuels (oil, coal and natural gases) |
|---|---|
| Energy store | Chemical |
| Renewable or non-renewable | Non-renewable |
| Uses | Transport, heating, electricity generation |
| Power output | High |
| Impact on environment | Releases CO2 (causes global warming) |
| Energy | Nuclear fuels |
|---|---|
| Energy store | Nuclear |
| Renewable or non-renewable | Non-renewable |
| Uses | Electricity generation |
| Power output | Very high |
| Impact on environment | Radioactive waste (needs to be disposed of safely) |
| Energy | Biofuel |
|---|---|
| Energy store | Chemical |
| Renewable or non-renewable | Renewable |
| Uses | Transport, heating, electricity generation |
| Power output | Medium |
| Impact on environment | Carbon-neutral so low impact |
| Energy | Wind |
|---|---|
| Energy store | Kinetic |
| Renewable or non-renewable | Renewable |
| Uses | Electricity generation |
| Power output | Very low |
| Impact on environment | Take up large areas that could be used for farming, people say windmills spoil their view |
| Energy | Hydroelectricity |
|---|---|
| Energy store | Gravitational potential |
| Renewable or non-renewable | Renewable |
| Uses | Electricity generation |
| Power output | Medium |
| Impact on environment | Local habitats are affected by the large areas that need to be flooded to build dams |
| Energy | Geothermal |
|---|---|
| Energy store | Internal |
| Renewable or non-renewable | Renewable |
| Uses | Electricity generation, heating |
| Power output | Medium |
| Impact on environment | Very low |
| Energy | Tides |
|---|---|
| Energy store | Kinetic |
| Renewable or non-renewable | Renewable |
| Uses | Electricity generation |
| Power output | Potentially very high but hard to harness |
| Impact on environment | Tidal barrages can block sewage which needs to go out to sea |
| Energy | Sun |
|---|---|
| Energy store | Nuclear |
| Renewable or non-renewable | Renewable |
| Uses | Electricity generation |
| Power output | Potentially very high, but hard to harness |
| Impact on environment | Very little |
| Energy | Water waves |
|---|---|
| Energy store | Kinetic |
| Renewable or non-renewable | Renewable |
| Uses | Electricity generation |
| Power output | Low |
| Impact on environment | Very low |
Comparing resources
Power stations that use Natural, finite fuel formed from the remains of living organisms, eg oil, coal and natural gas. or nuclear fuel are very reliable sources of energy. These two types of stations provide much of the UK鈥檚 electricity. They operate almost continuously. When additional power is needed, gas power stations are usually used because they will come on very quickly and start generating electricity almost immediately.
The fuel for nuclear power stations is relatively cheap, but the power stations themselves are expensive to build. It is also very expensive to dismantle, or To deactivate or remove in a safe manner., old nuclear power stations at the end of their useful life. The highly When unstable atoms give off particles that can be harmful to humans. waste needs to be stored for millions of years before the natural The number of decays of a radioactive element per second. Measured in Becquerels (Bq). will reduce to a safe level.
Water power eg tidal and Electricity that is generated by the movement of water. are reliable and predictable because of the Moon causing the tides and rainfall filling reservoirs. These two types can also be used to supply additional demand. But many of the renewable sources are unreliable, including wind and solar energy, and cannot respond to increased demand - sunny and windy weather cannot be guaranteed.
Renewable resources have no fuel costs, but the equipment used is expensive to build.