She says the firm admits low wholesale charges have helped it to make vast margins on the bills it dishes out to customers, although such costs are now on the rise.
"This begs the question, yet again, of why customers have seen only tiny price cuts when wholesale costs have been so low for so long, yet suppliers hike prices as soon as wholesale costs start to edge up," states Ms Gallacher.
The European Commission has found recently that homeowners across the continent could save a total of €13 billion (£11.01 billion) if they compare dual fuel prices and switch to the cheapest tariff.
Posted by Jim Tidy
Click here to run an energy price comparison, and see if you could be paying less for your gas and electricity.