THE Big Six energy firms are facing the prospect of a full-scale inquiry into their prices amid growing pressure from consumers.
The leading gas and electricity suppliers - including ScottishPower and Scottish and Southern Energy (SSE) - will find out this week if they face a major investigation.
Consumer group Which? and the Federation of Small Business (FSB) have sent a joint submission to the Office of Fair Trading (OFT), Ofgem and the Competition and Markets Authority, saying competition needs to be increased in the sector to give customers a fairer deal.
The groups said nine in 10 consumers believed the energy market should be referred for further scrutiny, while seven in 10 were worried about prices and only one in five trusted the firms.
The financial and energy regulators have been reviewing the working of the market for the past three months and are due to publish a final report within days. There is speculation that the report could trigger a full competition inquiry, which could see the firms forced to change pricing policies.
Yesterday's calls by Which? and the FSB come just over a month after it was revealed the six main energy companies received more than 5.5 million complaints last year. These ranged from issues with bills and metering to service, switching and payments.
Of the 5.5 million complaints, Npower received 1.3 million - the most of all six firms. It was followed by EDF and British Gas with 1.2 million and E.ON with 929,230. SSE and Scottish Power received 482,582 and 308,648 respectively.
In January, the energy giants were accused of complacency over power cuts during storms the previous month that left thousands of homes across Scotland without electricity.
Tim Yeo, Tory chairman of the House of Commons Energy Committee, said firms were taking advantage of their position as an effective monopoly to "neglect" customers.
Which? and the FSB insisted ever-rising energy bills were a "major concern" for households and small businesses.
"It is clear the energy market is broken and urgently needs fixing. Top of our concerns is the need to increase competition and to make trading transparent. For too long the lack of competition in the energy market has not been addressed. It is now time for radical changes that deliver an effective, competitive market that works for everyone, before the scale of this crisis worsens," they wrote.
"We all want to see a transparent market where consumers and businesses alike can understand their bills, compare prices and switch easily.
"We want to see the presence of strong competition right across the industry drive affordable pricing that gives everyone the confidence they are paying a fair price for their energy."
Labour MP Caroline Flint, the shadow energy and climate change secretary, said rising energy bills were causing a cost-of-living crisis. She added: "Consumers need to be confident that the energy market works for them and the prices they pay are fair."
An SNP spokesman said successive Westminster governments had failed to regulate the energy market and provide fair prices for consumers.
Power companies have repeatedly claimed their industry is being used as a political football.
The OFT said last night it would not be commenting on yesterday's letter from Which? and the FSB. "Ofgem and ourselves are due to report this week," a spokesman said. "Our report this week will say what our position is."