Distribution Network Operator

Distribution network operators (DNOs) are companies licensed to distribute electricity in Great Britain by the Office of Gas and Electricity Markets.

There are fourteen licensed geographically defined areas, based on the former area electricity board boundaries, where the distribution network operator distributes electricity from the transmission grid to homes and businesses. Under the Utilities Act 2000 they are prevented from supplying electricity; this is done by a separate electricity supply company, chosen by the consumer, who makes use of the distribution network.

Distribution network operators are also responsible for allocating the core Meter Point Administration Number used to identify individual supply points in their respective areas, as well as operating and administering a Meter Point Administration System that manages the details relating to each supply point. These systems then populate ECOES, the central online database of electricity supply points. Their trade association is the Energy Networks Association.

In 1990, the area boards were replaced by regional electricity companies, which were then privatised. The distribution network operators are the successors to the distribution arms of the regional electricity companies. The distribution network operators have a trade association called the Energy Networks Association

At September 2013, six company groups hold the fourteen distribution licences:

In addition to the distribution network operators noted above who are licensed for a specific geographic area there are also independent distribution network operators (IDNO). IDNOs own and operate electricity distribution networks which will predominantly be network extensions connected to the existing distribution network, e.g. to serve new housing developments. Scottish Hydro Electric Power Distribution also provide distribution services in South Scotland as an IDNO and Southern Electric Power Distribution provide IDNO services in all other England and Wales areas. The IDNOs have no geographically defined "base" area.

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