A distribution network operator (DNO), also known as a distribution system operator (DSO), is the operator of the electric power distribution 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, 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, 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 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:

GSP Group ID Area ID TLF Zone Area DNO company Group Former area electricity board MPAS Operator ID _A 10 1 East England Eastern Power Networks plc UK Power Networks Eastern Electricity EELC _B 11 2 East Midlands National Grid Electricity Distribution (East Midlands) plc National Grid Electricity Distribution East Midlands Electricity EMEB _C 12 3 London London Power Networks plc UK Power Networks London Electricity Board LOND _D 13 4 North Wales, Merseyside and Cheshire SP Manweb plc SP Energy Networks MANWEB MANW _E 14 5 West Midlands National Grid Electricity Distribution (West Midlands) plc National Grid Electricity Distribution Midlands Electricity MIDE _F 15 6 North East England Northern Powergrid (Northeast) plc Northern Powergrid North Eastern Electricity Board NEEB _G 16 7 North West England Electricity North West Limited Electricity North West NORWEB NORW _P 17 14 North Scotland Scottish Hydro-Electric Power Distribution plc Scottish and Southern Electricity Networks North of Scotland Hydro-Electric Board HYDE _N 18 13 South and Central Scotland SP Distribution plc SP Energy Networks South of Scotland Electricity Board SPOW _J 19 9 South East England South Eastern Power Networks plc UK Power Networks Seeboard SEEB _H 20 8 Southern England Southern Electric Power Distribution plc Scottish and Southern Electricity Networks Southern Electric SOUT _K 21 10 South Wales National Grid Electricity Distribution (South Wales) plc National Grid Electricity Distribution SWALEC SWAE _L 22 11 South West England National Grid Electricity Distribution (South West) plc National Grid Electricity Distribution SWEB SWEB _M 23 12 Yorkshire Northern Powergrid (Yorkshire) plc Northern Powergrid Yorkshire Electricity YELG

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.

Area ID Name Licensee MPAS Operator ID 24 Envoy Independent Power Networks IPNL 25 ESP Electricity ESP Electricity LENG 26 Last Mile Electricity Last Mile Electricity GUCL 27 GTC The Electricity Network Company Ltd ETCL 28 EDF IDNO UK Power Networks (IDNO) Ltd EDFI 29 Harlaxton Energy Networks Ltd Harlaxton (IDNO) HARL 30 Leep Electricity Networks Ltd Leep Electricity Networks (IDNO) PENL 31 UK Power Distribution Ltd UK Power Distribution Ltd UKPD 32 Energy Assets Networks Ltd Energy Assets Networks Ltd. UDNL 33 Eclipse Power Networks Eclipse Power Networks GGEN 34 mua Electricity Ltd mua Electricity Ltd MPDL 35 Fulcrum Electricity Assets Fulcrum Electricity Assets FEAL 36 Vattenfall Networks Ltd Vattenfall Networks Ltd VATT37Optimal Power NetworksOptimal Power NetworksFORB38Indigo Power LimitedIndigo Power LimitedINDI39Squire Energy Metering LtdSquire Energy Metering LtdSTRK40Utility Assets LimitedUtility Assets LimitedUTAL42Advanced Electricity NetworksAdvanced Electricity NetworksAENL43IDCS LtdIDCS LtdIDCS

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