A distribution network operator (DNO), also known as a distribution system operator (DSO), is the operator of the
electric power distribution
Electric power distribution is the final stage in the Power delivery, delivery of electricity. Electricity is carried from the Electric power transmission, transmission system to individual consumers. Distribution Electrical substation, substatio ...
system which delivers electricity to most end users. Each country may have many local distribution network operators, which are separate from the
transmission system operator (responsible for transporting power in bulk around the country).
France
In
France
France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...
,
Enedis, a subsidiary of
EDF, distributes approximately 95% of electricity, with the remaining 5% distributed by 160 local electricity and gas distribution companies (''entreprises locales de distribution d'électricité et de gaz'' or ELD).
[ Jean Proriol]
Rapport d'information No. 3307 déposé par la commission des affaires économiques de l'Assemblée nationale
assemblee-nationale.fr du 5 avril 2011, consulté le 30 avril 2020
Great Britain
In
Great Britain
Great Britain is an island in the North Atlantic Ocean off the north-west coast of continental Europe, consisting of the countries England, Scotland, and Wales. With an area of , it is the largest of the British Isles, the List of European ...
, distribution network operators are licensed 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 (Electricity Central Online Enquiry Service), the central online database of electricity supply points. Their
trade association
A trade association, also known as an industry trade group, business association, sector association or industry body, is an organization founded and funded by businesses that operate in a specific Industry (economics), industry. Through collabor ...
is the Energy Networks Association.
History

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.
, six company groups hold the fourteen distribution licences:
IDNOs
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.
Building network operators
A further, smaller level of distribution is the building network operator (BNO), usually a company employed by the building owner, in a large building with many meters, such as a block of private flats.
In this case, the DNO may act as BNO and its responsibility may include the sub-mains to the individual flats, or DNO responsibility may end at the first incomer, in which case the independent BNO is responsible for the secure distribution cabling 'laterals' between that point and the individual fuses and meters.
Historically such cabling would have been maintained and sealed by electricity boards that preceded the DNOs, and different DNOs supplying buildings of different sizes and conditions, may choose to adopt the wiring in the building or to insist that an independent BNO is appointed. Unlike a DNO or an IDNO, BNOs may be exempted from any licensing requirement by schedules 2 and 3 of The Electricity (Class Exemptions from the Requirement for a Licence) Order 2001
and this allows those responsible for the building network (such as a housing association) to employ any suitable electrical contractor on an ad-hoc basis.
Canada
In Canada, the distribution network operators are known as local distribution companies (LDC).
LDCs normally buy their power from larger companies, sometimes ones dedicated solely to wholesale supply. They re-sell it to the smaller customer. Larger customers typically buy their power directly from the wholesaler, and do not use the LDC.
See also
*
Electricity distribution companies by country
*
Meter Point Administration Number
*
Northern Ireland Electricity
References
External links
Energy Networks Association the trade association for distribution network operators
Electricity Central Online Enquiry Service
{{Electricity generation
Electric power distribution