The story
Founded by Government of Ireland in 2001.1
EirGrid was established under Irish and European laws including the European Communities (Internal Market in Electricity) Regulations, 2000, to enable competition in the Irish power sector. It took over operation of the national power system on 1 July 2006. The ESB (the Electricity Supply Board) currently holds ownership of the physical assets.
The transmission assets constitute 6,500 km of overhead line and underground cable, as well as over 100 bulk substations. The system's significance for competition is that most large independent generators connect to the transmission system and utilise it to transport their power to all regions. EirGrid also operates the wholesale power market.
From Wikipedia’s article on EirGrid, shared under CC BY-SA 4.0.4