Greg Bourne, a former president of BP Australasia and an energy adviser to former British prime minister Margaret Thatcher, will tell a Senate inquiry on Tuesday that governments have failed to deliver the Australian people a fair share of their gas resources.
Momentum has been building behind a push for a 25 per cent tax on gas export revenues, which left-leaning think tank the Australia Institute claims would raise an extra $17 billion per year for the federal budget.
A broad array of crossbenchers, Liberal industry spokesman Andrew Hastie, Labor backbencher Ed Husic and Commonwealth Bank chief executive Matt Comyn have supported raising taxes on gas exporters in the May budget.
Mr Bourne, now a member of the Climate Council, says governments have made a "Faustian bargain" with the gas industry and the average Australian has little to show for it.
"You become beholden to the companies, and very little money actually comes to the Australian people," he told AAP.
Mr Bourne's former employer, BP, argued in its submission to the inquiry that a 25 per cent export levy would make future gas projects uneconomic.
Peak body Australian Energy Producers, which points out the oil and gas industry paid almost $22 billion in taxes and royalties in 2024/25, argues raising taxes would discourage new investment in Australia, pushing companies to explore new projects elsewhere.
But Mr Bourne said the government should ignore the industry's threats that it would walk away.
Their leverage has eroded. Viable gas projects were becoming increasingly scarce and demand for fossil fuels was set to decrease in coming decades as the world transitioned to renewables and battery storage, he said.
Gas companies were like "cornered rats", fighting tooth and nail to maintain the status quo, Mr Bourne said.
The Senate committee will also hear from several other witnesses in favour of increased taxes on gas companies on Tuesday, including former Greens leader and current Australian Conservation Foundation chief executive Adam Bandt, and economist Ross Garnaut.
Mr Garnaut, who is director of The Superpower Institute, will argue for Australia to emulate the Norwegian model, of a two-way cash-flow tax, which shares the risks of investing in projects while retaining the benefits of windfall profits.
Greens senator Steph Hodgins-May slammed the gas companies for refusing to send chief executives to front up to the inquiry on Wednesday and Friday.
"They are making billions of dollars off Australian gas and are set to make war time profits, and while Australians are being rinsed, they refuse to front up and give evidence," she told reporters.
Shell will send their most senior executive in Australia to front the inquiry, but the others will send lower-ranking executives or policy staff.