The 2003 London blackout was a serious power outage that affected parts of south London and north-west Kent in the evening of 28 August 2003. It was caused by a series of faults at National Grid transmission substations, which supplied the distribution network operator in the area, EDF Energy.
Scottish Power is a vertically integrated energy company based in Glasgow, Scotland. It is a subsidiary of Spanish utility firm Iberdrola.
The National Grid is the high-voltage electric power transmission network serving Great Britain, connecting power stations and major substations, and ensuring that electricity generated anywhere on the grid can be used to satisfy demand elsewhere. The network serves the majority of Great Britain and some of the surrounding islands. It does not cover Northern Ireland, which is part of the Irish single electricity market.
Centrica plc is a British multinational energy and services company with its headquarters in Windsor, Berkshire. Its principal activity is the supply of electricity and gas to consumers in the United Kingdom and Ireland.
National Grid plc is a British multinational electricity and gas utility company headquartered in London, England. Its principal activities are in the United Kingdom, where it owns and operates electricity and natural gas transmission networks, and in the Northeastern United States, where as well as operating transmission networks, the company produces and supplies electricity and gas, providing both to customers in New York and Massachusetts.
Public electricity suppliers (PES) were the fourteen electricity companies created in Great Britain when the electricity market in the United Kingdom was privatised following the Electricity Act 1989. The Utilities Act 2000 subsequently split these companies between distribution network operators and separate supply companies.
A Meter Point Administration Number, also known as MPAN, Supply Number or S-Number, is a 21-digit reference used in Great Britain to uniquely identify electricity supply points such as individual domestic residences. The system was introduced in 1998 to aid creation of a competitive environment for the electricity companies, and allows consumers to switch their supplier easily as well as simplifying administration. Although the name suggests that an MPAN refers to a particular meter, an MPAN can have several meters associated with it, or indeed none where it is an unmetered supply. A supply receiving power from the network operator (DNO) has an import MPAN, while generation and microgeneration projects feeding back into the DNO network are given export MPANs.
EDF Energy is a British integrated energy company, wholly owned by the French state-owned EDF, with operations spanning electricity generation and the sale of natural gas and electricity to homes and businesses throughout the United Kingdom. It employs 11,717 people, and handles 5.22 million business and residential customer accounts.
The energy policy of the United Kingdom refers to the United Kingdom's efforts towards reducing energy intensity, reducing energy poverty, and maintaining energy supply reliability. The United Kingdom has had success in this, though energy intensity remains high. There is an ambitious goal to reduce carbon dioxide emissions in future years, but it is unclear whether the programmes in place are sufficient to achieve this objective. Regarding energy self-sufficiency, UK policy does not address this issue, other than to concede historic energy security is currently ceasing to exist.
E.ON UK is a British energy company and one of the largest suppliers of energy in the UK, following its acquisition of Npower. It is a subsidiary of E.ON of Germany and one of the Big Six energy suppliers. It was founded in 1989 as Powergen, and was listed on the London Stock Exchange and was once a constituent of the FTSE 100 Index. It has been a subsidiary of E.ON since 1 July 2002.
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.
Eastern Electricity plc was an electricity supply and distribution utility serving Eastern England, including East Anglia and part of Greater London. It was renamed Eastern Group under which name it was listed on the London Stock Exchange and was a constituent of the FTSE 100 Index until it was acquired by Hanson plc in 1995, before being purchased by Texas Utilities in 1998.
Seeboard, formerly South Eastern Electricity Board (SEEB), was a British electricity company. The electrical power industry in the United Kingdom was nationalised by the Electricity Act 1947, when over 600 electric power companies were merged into 12 area boards, one of which was the South Eastern Electricity Board. It acquired the former Princes Hotel on the seafront in Hove, East Sussex, and converted it into its headquarters. The building was refurbished and substantially extended between 1979 and 1981.
SP Manweb is the regional electricity distribution network operator (DNO) for Merseyside, North Wales and parts of Cheshire. It is now part of SP Energy Networks, itself a subsidiary of the Spanish energy company Iberdrola.
24seven, or 24seven Utility Services Ltd. was a utility management company that supplied over 5 million homes with electricity in the early part of the 21st century.
In the United Kingdom, an electricity supplier is a retailer of electricity. For each supply point the supplier has to pay the various costs of transmission, distribution, meter operation, data collection, tax etc. The supplier then adds in energy costs and the supplier's own charge. Regulation of the charging of customers is covered by the industry regulator Ofgem.
Electricity North West Limited is a British electricity distribution network operator, responsible for the administration and maintenance of the network, that distributes electricity to the North West of England excluding Merseyside and parts of Cheshire.
The Big Six were the United Kingdom's largest retail suppliers of gas and electricity, who dominated the market following liberalisation in the late 1990s. By 2002, six companies – British Gas, EDF Energy, E.ON, RWE npower, Scottish Power and SSE – had emerged from the 15 former incumbent monopoly suppliers.
CK Hutchison Holdings Limited is a Hong Kong–based and Cayman Islands–registered multinational conglomerate corporation. The company was formed in March 2015 through the merger of Cheung Kong Holdings and its main associate company Hutchison Whampoa. It has four core businesses – ports and related services, retail, infrastructure and telecommunications – which operate in over 50 countries, as well as several other investments around the world.
Scottish and Southern Electricity Networks is one of two energy companies in the UK to be involved both in electricity transmission and distribution.
£ 1,760 million (March 2021) [1] 
