Operating profit at semi-state ESB hit €337m in the six months to the end of June, compared to the €327m recorded in the same period last year.
The €10m increase excluded exceptional items.
Revenue increased from €1.65bn to €1.72bn while earnings before deductions rose from €665m to €690m.
Pre-tax profits at the group jumped from €113m to €236m while profits after tax almost doubled to €201m from €108m.
The ESB made a dividend payment of €224m, a €12m decrease on the dividend paid out in the first half of 2014.
The company says that it has achieved cost savings of more than €270m since 2010.