Queensland energy industry leaders are lining up for what should be a fiery public meeting this week.

The heads of state-owned power companies Energex and Ergon are expected to justify their plans for more power price rises, despite falling demand and costs.

The public meeting was called by the Australian Energy Regulator (AER), just after a whistleblower claimed in September that the companies were manipulating data to target a higher rate of return.

The fixed rate of return guarantees a set return on network spending, which is then passed on to consumers. Currently, these network charges make up about 50 per cent of household power bills.

Now, Energex and Ergon have made revenue bids asking for price rises of just under inflation over five years, and will have to explain why.

Consumer advocates are expected to be thick on the ground and tomorrow’s meeting, arguing that the revenue bids are excessive and that prices should in fact be driven down.

They say years of free-wheeling network spending have contributed to electricity price rises of 80 per cent in the last six years.

A recent AER issues paper pointed to the rate of return on investment proposed by Ergon and Energex in their revenue bids as key issues for review.

The power companies could be in for a shock, if the AER’s call in New South Wales is anything to go by.

The regulator took a big chunk out of NSW revenue bids in recent week, with draft determinations that the revenue be slashed a third of that requested.

But Ergon and Energex have proposed higher returns than AER guidelines advised in regard to NSW. The Queensland companies want about 8 per cent, compared with 7 per cent in the AER’s NSW determinations.

Experts say that a fall of even 1 per cent fall could amount to as much as a 20 per cent drop in electricity bills.