Sources of energy
There are different energy sources in the world and the stores of energy associated with them can contain different amounts of energy. For example, nuclear fuel stores can contain very large amounts of energy, while Electricity that is generated by the movement of water. stores tend to contain much less energy.
Some energy sources are renewable, which means they can be replenished and will not run out. Other energy sources are non-renewable, which means they will eventually run out when all their reserves have been depleted (used up).
The table below shows the main features of the most common energy sources 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, which contributes to global warming. |
| Nuclear fuels | Nuclear | Non-renewable | Electricity generation | Very high | Produces radioactive waste which 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 | Turbines take up large areas that could be used for farming. Some people say windmills spoil the view. |
| Hydroelectricity | Gravity | Renewable | Electricity generation | Medium | Local habitats are affected by the large areas that need to be flooded to build dams. |
| 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 and heating | Dependant on the weather and only available during daylight | Impact on environment is very low. |
| Energy resource | 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, which contributes to global warming. |
| Energy resource | Nuclear fuels |
|---|---|
| Energy store | Nuclear |
| Renewable or non-renewable | Non-renewable |
| Uses | Electricity generation |
| Power output | Very high |
| Impact on environment | Produces radioactive waste which needs to be disposed of safely. |
| Energy resource | Biofuel |
|---|---|
| Energy store | Chemical |
| Renewable or non-renewable | Renewable |
| Uses | Transport, heating, electricity generation |
| Power output | Medium |
| Impact on environment | 'Carbon neutral' - little or no effect on the environment. Although growing biofuels can take up land that could be used for farming. |
| Energy resource | Wind |
|---|---|
| Energy store | Kinetic |
| Renewable or non-renewable | Renewable |
| Uses | Electricity generation |
| Power output | Very low |
| Impact on environment | Turbines take up large areas that could be used for farming. Some people say windmills spoil the view. |
| Energy resource | Hydroelectricity |
|---|---|
| Energy store | Gravity |
| 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 resource | 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 resource | Sun |
|---|---|
| Energy store | Nuclear |
| Renewable or non-renewable | Renewable |
| Uses | Electricity generation and heating |
| Power output | Dependant on the weather and only available during daylight |
| Impact on environment | Impact on environment is very low. |
Resources compared
Power stations
- Very reliable sources of energy – this is part of the reason why these types of energy are relied upon to provide much of the country's electricity.
- They operate almost continuously. When additional power is needed, gas power stations are usually used because they will activate 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.
Renewable sources
- Examples of renewables include wind, solar, hydroelectric power.
- No fuel costs, but the equipment used is expensive to build.
- Many of the sources are unreliable. For example, wind and solar energy are dependent on the weather and cannot respond to increased demand.
- Water power, ie Energy generated from the movement of tides. and hydroelectric, are reliable because their sources (the Moon's gravitational effect on the tide and rainfall that fills reservoirs) are regular and predictable occurrences. These types of energy can also be used to supply additional demand.