Electricity distribution

Electricity distribution is the penultimate process in the delivery of electric power from generation to the consumer. The other main processes are transmission and retailing. In the early days of electricity generation, direct current (DC) generators were connected to loads at the same voltage. This imposed limitations on how far the distribution system could extend because of the voltage drop[?]. It also meant that cables and lines had to be made from relatively large diameter copper in order to carry the high currents required to meet the demand of distributed load. (Power lost in generating heat in a conductor is proportional to the square of the current ie Losses = I*I*R. These losses can be reduced by reducing the resistance (R) of the conductor, hence increasing the diameter; or, more effectively, by reducing the current (I).)

The adoption of alternating current (AC) for electricity generation dramatically changed the situation. Power transformers could be used to raise the voltage from the generators and reduce it to supply loads. Increasing the voltage reduced the current and hence the size of conductors and distribution losses, making it more economic to distribute power over long distances. Distribution voltages range up to 33,000 volts whereas the voltage at residential premises is 110 volts or 230 volts depending on the country has standard. The ability to transform to extra-high voltages enabled generators to be located far from loads and transmission systems to interconnect generating stations and distribution networks[?].

Electricity industry reform has lead to the creation of electricity markets through the separation of contestable retailing from distribution, a natural monopoly and the separation of the monopoly transmission from generation. It also lead to the development of new terminology to describe the distributor such as Line company[?], Wires Business[?] and Network Company[?].

See also Distributed generation.