The CER issues two licences in relation to the transmission system in Ireland; the Transmission System Operator (TSO) Licence and the Transmission Asset Owner (TAO) licences
TSO Licence
The licence to operate the Irish Transmission system was granted by the CER to EirGrid in accordance with Statutory Instrument No. 445 of 2000 and came into effect on 1 July 2006, the same date that EirGrid was established. On 3rd July 2007 the Regulatory Authorities issued to EirGrid the modified version of the Transmission System Operator licence designed to facilitate the operation of the Single Electricity Market. An updated Transmission System Operator licence, which came into legal effect on 2nd March 2009 and took account of the acquisition of SONI Limited by Eirgrid Plc. was issued to Eirgrid on 7th September 2009.
EirGrid is a state owned company that was set up specifically to carry out the TSO function and it is separate and independent from the ESB which actually owns the transmission system.
EirGrid's responsibilities include the operation, maintenance and development of Ireland's transmission system in a safe, secure, reliable, economical and efficient manner. It also offers terms and levies charges for the connection to and use of the system by market participants and these tariffs are regulated by the CER.
Transmission System Operator (TSO) Licence - Issued 3 July 2007
Previous TSO licence - Issued 1 July 2006
TAO Licence
The assets that make up the transmission network are not owned by EirGrid, but by ESB. The activity of owning the transmission system assets is a separately licensed activity and the TAO licence was granted by CER to ESB in 2001 in accordance with Statutory Instrument No. 445 of 2000. The TAO is required to maintain the transmission system and carry out construction work for its development in accordance with the TSO's Transmission Development Plan.
Infrastructure Agreement
Because of the structural split between the ownership and the operation of the transmission system, an infrastructure agreement has been drawn up between the TSO and TAO to govern the ongoing relationship between the two organisations. The agreement has been approved by CER and came into effect on 1 July 2006 - the same date as the legal establishment of EirGrid as the TSO.