Gas companies are "poster child tax avoiders" which should be made to pay a greater share of revenue to fund essential services, Greens leader Adam Bandt says.
Mr Bandt will tell the National Press Club on Wednesday the gas industry should fork out more tax and royalties to help ease cost of living pressures for Australians.
"In a country where one in three big corporations pays no tax, the gas industry are poster child tax avoiders," Mr Bandt will say.
"They're not just profiteering off a Russian dictator's invasion of Ukraine, they're driving up energy costs in Australia as well, all while giving next to nothing to the public purse."
Mr Bandt will say billions of dollars are being sent offshore by corporations, saying in one year 27 companies paid zero tax after raking in $77 billion in revenue.
"When a nurse pays more tax than a billionaire corporation, something is seriously wrong," he will say.
"The gas tax laws in this country are broken and our country is being taken for a ride."
Households and businesses are facing skyrocketing energy costs, with a report released by the Australian Competition and Consumer Commission revealing a gas shortfall could occur in 2023 if all excess gas produced by exporters was sent overseas.
In response, the federal government announced on Monday it would extend the "gas trigger" mechanism to 2030 - which would divert gas exports to the domestic market - and issue a notice of intent to invoke the mechanism.
However, the gas industry insists there will be enough supply to cover any forecast shortfall.
Mr Bandt will say childcare should be made free, and dental included in Medicare to provide cost of living relief when the Albanese government hands down its new budget in October.
This would be fully funded by a tax on billionaires and gas corporations.
Families could save almost $7000 a year under these changes, the Greens say.
"People need help with the cost of living urgently," Mr Bandt says.
"The numbers are there in the parliament. The only thing standing in the way is Labor's willingness to act."
Taking a swipe at both the government and opposition, Mr Bandt will label Labor "the party of the centre-right" and the Liberals "irrelevant".
"The Greens are now the only social democratic party in Australia. We see it as our job to get the country back to a fairer place," he says.
