Electricity is a convenient source of energy and can be generated in a number of different ways using either fossil fuels or renewable and sustainable technologies.
Power stations fuelled by fossil fuels or nuclear fuels are reliable sources of energy, meaning they can provide power whenever it is needed. However, their start-up times vary according to the type of fuel used.
This list shows the type of fuel in order of start-up time:
gas-fired station (shortest start-up time)
oil-fired station
coal-fired station
nuclear power station (longest start-up time)
Nuclear power stations and coal-fired power stations usually produce the minimum level of electricity required by the National Grid over a period of 24 hours. This is called base load electricity.
Nuclear and coal fired power stations are run all the time because they take the longest time to start up. 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 old nuclear power stations and to store their radioactive waste, which is a health hazard.
Renewable resources
Renewable resources of fuel such as energy from the Sun and wind energy do not cost anything, however the equipment used to generate the power may be expensive to build.
Certain resources are reliable, including tidal barrages and hydroelectric power. Others are less reliable, including wind and solar. Hydroelectric power stations have a very short start up time and are used to supply electricity quickly when the demand is high.