The head of the Commission for Energy Regulation says he will take action if electricity suppliers don't pass on savings to consumers.
The statement comes after a higher-than-expected rise in the PSO levy on electricity bills - which will see the average consumer pay €73 a year after VAT.
The increased levy comes as energy providers avail of falling wholesale electricity prices.
Garett Blaney, Chairperson of the CER says those savings should be passed on to customers.
"Some of our consumers, the large consumers, actually can see it instantaneously," he said.
"We carefully monitor the market, and we'll take action if we see that the suppliers aren't passing those costs through".