Electricity is one of the cleanest forms of power and an essential part of our lives. In order to generate electricity, other energy sources are used, for example:
- Coal, gas, oil, waster and nuclear fusion are converted into steam and then into electricity via conventional rotating plants.
- Water, wind and tidal energy are directly converted to electricity via rotating plants.
- Sunlight is converted directly to electricity via solar panels.
Distribution of electricity
The initial stage in the distribution of power is to transfer the electricity from the power station to a distribution centre. Due to the large amount of power that is to be transferred, the cables required need to operate at extra high voltage (66-275,000 volts). The cheapest form of transfer of extra high voltage power is through the use of overhead lines, in which the air is the insulation. Therefore, in most case, power is transferred from the power station to a distribution centre (also called a substation) by bare wires supported by massive steel towers.
The power is then transferred from the substation to local suburbs. This is usually done at a lower voltage (11-33,000 volts), however this is still higher than normal usage, and is therefore transferred either by overhead lines or specially designed underground cables. The power is distributed from the substation to a transformer located either within a factory or close to houses in residential areas.
The transformer converts the electricity from its current high voltage to low voltage (600 – 1,000 volts) for use within the home, office or factory. The electricity is supplied to the buildings via insulated aerial bundled cables or underground cables.
Within the house, factory or office, insulated cables are used for power points and connection to electrical equipment. There may also be cables for communications and data which operate at even lower voltages.