Ireland is being taken to the European Court of Justice for failing to up competitiveness in the electricity market.
The EU electricity Directive to increase competition was introduced in 2011. Ireland could be liable for a fine of €20,000 each day.
"Ireland has failed to take the various steps needed to introduce greater competition to the energy market," said Peter Power of the EU office in Dublin.
"Greater competition in the energy market means better prices for consumers … the commission wants a separation of the energy production and supply activates from the networks, in order to bring other players into this market."