Structure of UK electricity industry

Generation is the production of electricity.  Electricity is produced either in power stations that burn coal, gas or oil or use nuclear fuel, or from renewable sources such as wind and water.  Generation is a competitive market.

Transmission is the bulk transport of electricity by high voltage power lines from power stations to grid supply points.  The transmission system is generally referred to as the national grid.  Transmission is a regulated monopoly business.

Distribution is the transport at a regional level of electricity at gradually reducing voltages from national grid supply points to final customers, both commercial and domestic.  Distribution is a regulated monopoly business.

Supply is the process of buying electricity in bulk and selling it on to the final customer.  Suppliers pay for their electricity to be transmitted across the national grid and the local distribution network to their customers.  Electricity supply in the UK is a competitive market.

RWE npower participates in the generation and supply segments of the electricity industry.

Up to March 2005 the electricity industries of Scotland, Northern Ireland and England and Wales operated independently, although interconnectors joined all three grid systems together. From April 2005 under the British Electricity Trading and Transmission Arrangements (BETTA), introduced in the Energy Act 2004, the electricity systems of England and Wales and Scotland have been integrated.