The number of households who are behind on their electricity bills has surged 13.5% in the last two months.
Figures handed to the Oireachtas Environment Committee by the Commission for Regulation of Utilities (CRU) show that 240,791 households were in arrears on their electricity bills in May.
That is up from 211,855 in February.
Meanwhile, the number of homes in gas arrears rose 8.5% from 152,276 in February to 165,206 in May.
It means an extra 23,453 domestic electricity and 1,137 domestic gas customers fell into arrears between April and May alone.
The increases came as the Government's electricity credits were coming to an end.
Sinn Fein climate action spokesperson Darren O'Rourke told Newstalk the figures show the credit schemes did not go far enough.
“We have had on the one hand, the direct intervention from Government - the three €200 electricity credits - and at exactly the same time, we have increasing numbers in electricity arrears – in the region of 10%,” he said.
“Month-on-month it is even higher – it is at 20%.”
He said more needs to be done to pressurise energy companies to drop their prices.
“We have no indication or no oversight because of the lack of power of the CRU - the energy regulator,” he said.
“From Government, we have had nothing but lip service and an indication that they want to see prices reduced and they want to see those reductions in costs passed on.”
The CRU figures also show that 137 homes had their electricity cut off and 196 had their gas cut off for non-payment reasons in May.