Electricity sector in Ireland

The electricity sector in Ireland previously operated as two separate markets; Northern Ireland operated as part of the UK, and the Republic of Ireland operated its own separate market. On 1 November 2007 the two Transmission System Operators (System Operator Northern Ireland and EirGrid) established the Single Electricity Market (SEM) for the island of Ireland. The SEM has created "a gross mandatory pool market, into which all electricity generated on or imported onto the island of Ireland must be sold, and from which all wholesale electricity for consumption on or export from the island of Ireland must be purchased." According to the Electricity Association of Ireland: EAI, The Single Electricity Market (SEM) is a market of approximately 2.5 million customers; 1.8 million in the Republic and 0.7 million in Northern Ireland. The effect of Brexit on the SEM has yet to be defined.

Electricity generators in the Republic of Ireland are ESB, Airtricity, Synergen (70% ESB), Edenderry Power, Endesa-Ireland and Huntstown (Viridian). ESB owns the transmission and distribution networks.

The Transmission System Operator (TSO) is EirGrid plc, which assumed the role from ESB Networks on 1 July 2006. EirGrid ensures the safe, secure and economic operation of the high voltage electricity grid. EirGrid is owned by the Irish State and is established as a result of a government decision to create an independent organisation to carry out the TSO function, in order to assist the liberalisation of Ireland's electricity industry and the development of a competitive market.

The electricity industry is regulated by the Commission for Energy Regulation (CER) which also regulates the natural gas market. The functions and duties of the CER have been altered and expanded significantly by legislation transposing EU directives into Irish law.

Electricity is regulated by the Northern Ireland Authority for Utility Regulation. There are three power stations in the province: Ballylumford power station, Coolkeeragh power station and Kilroot power station. Northern Ireland Electricity (a subsidiary of ESB Group) owns the transmission and distribution networks.

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