The head of Australia's competition watchdog says the rules governing the setting of electricity prices are not working, and are a major factor behind a 90 per cent increase in power prices over the past five years.
Australian Competition and Consumer Commission (ACCC) chairman Rod Sims will make the case for change today when he addresses the annual conference of the Energy Users Association.
The Association represents major electricity consumers, including some of Australia's biggest companies including Rio Tinto, BHP Billiton, Coles and Woolworths.
He says the network companies running electricity infrastructure - the poles and wires which carry electricity to homes and businesses - have too much power in setting prices.
And he says major spending decisions to improve reliability have been made without properly considering if the benefit justifies the cost.
"Network prices have probably risen quite a lot more than they should have, and therefore consumers are paying more for electricity than they should be," Mr Sims told ABC News.
The ACCC chairman says the Australian Energy Regulator has been unfairly blamed, when it is hamstrung by the rules.
"The regulator's had two arms and two feet tied behind its back in trying to deal with these issues," he added.
Mr Sims warns that unreasonable increases to electricity prices will continue until the system that regulates them is fixed.
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