The Minister for Energy is insisting he has not sold Bord Gais Energy below its value.
The company was sold to a consortium, which includes Centrica, for €1.12bn yesterday, even though the original price was understood to be €1.4 bn.
Pat Rabbitte said the price is a good one, and was carefully considered.
"We had advisors to my Department … we have teased through this for a long time, and we had a good idea what the market could bear," he said.
He also claims the arrival of a big player into the Irish energy market is a good thing and will increase competition.
Sinn Fein Energy spokesperson Micheal Colreavy, however, said the Government ignored the potential for future development within the company.
He said Ireland could have enhanced its energy security through reform at the company, rather than selling it.