Treasurer Jim Chalmers has taken aim at petrol companies not passing on wholesale price drops to consumers as Australia again stares down an energy crisis.

Dr Chalmers says he’s been working with the Australian Competition and Consumer Commission to monitor bad behaviour and retail petrol price gouging.

“The service stations shouldn’t be treating drivers as mugs,” he told the Seven Network on Wednesday morning.

“People are absolutely filthy that when the international wholesale price goes up, the increases are passed on almost automatically and when the international price comes off a bit, it takes longer for the savings to be passed on.”

The cut to the petrol excise, which due to end in September, could not be continued forever due to the state of the budget, Dr Chalmers added. 

“There are serious pressures on the budget; it would cost some billions to extend it even for another six months. And so we need to be up front about that and we need to be responsible about it,” he told the ABC.

“What we’re seeing now is the wholesale international price of petrol has come off a bit.

“We call on the service stations to pass those savings on because Australians should be getting that petrol price relief now and not just reliant on the program that runs out in September.”

The treasurer’s concerns come with the Australian Energy Market Operator triggering the gas supply guarantee on Tuesday evening to secure supply from Queensland after shortages in Victoria.

Reserves at Victoria’s Iona gas storage facility in Port Campbell have dropped to record low supply levels due to high demand amid the state’s price cap.

Lochard Energy, which owns Iona, says “unplanned coal fired generation outages” and cold weather has increased demand.

“It is the case that gas supply and winter peaking capacity are becoming increasingly tighter on the east coast,” Lochard said in a statement.

By Dominic Giannini in Canberra

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