Responding to criticism of Prime Minister Anthony Albanese's Made in Australia Act, a group of energy and finance leaders joined forces on Thursday to call for the scale of budget support required for decarbonisation.

In a joint statement, they urged Treasurer Jim Chalmers to use the May budget to encourage investment, as rival economies throw trillions of dollars into renewable energy and clean tech to secure their national interests.

Dr Chalmers has been out vigorously defending the plan and used an appearance at G20 talks on Thursday to tell his global counterparts it would unlock more private investment, not replace it.

"This generation of policy makers will be judged on our success in building a net zero economy, fit to usher in a new era of prosperity," he said on Thursday.

The prime minister last week unveiled the Future Made in Australia Act aimed at funding new major manufacturing and clean energy projects.

Labor-picked Productivity Commission chair Danielle Wood was among those voicing concerns about the scheme, suggesting it could create a class of businesses reliant on government subsidies if it wasn't accompanied with a clear exit strategy.

But the clean energy industry says Australia can't afford to "sit out" the accelerating global transition and needs taxpayer support to unlock the private capital needed for zero-emissions economic opportunities.

The Clean Energy Investor Group, representing developers and investors with a combined $38 billion renewable energy portfolio and a project pipeline of almost 50 gigawatts, said the Act could unlock significant investment through the superannuation system.

Chief scientist at grassroots organisation Rewiring Australia Saul Griffith said the legislation would put Australia in step with other countries already investing in their own futures and ensure the profits do not flow overseas.

"It's a great opportunity for Australian households," Dr Griffiths said.

Climate Energy Finance think tank director Tim Buckley said the "ambitious and visionary" Made in Australia Act sets the nation up for the speed and scale of investment for a place in the global net-zero economy.

"We urge the government to hold its nerve and deliver an ambitious and coordinated package of budget incentives," Mr Buckley said.

This would enable Australia to pivot from the "historic over-dependence on fossil fuels" to a zero-emissions global trade and investment leader, he said.

Kane Thornton, CEO of the industry's Clean Energy Council, said the United States' Inflation Reduction Act had completely reshaped the global energy transformation in its first year.

"It is time for Australia to step up and prioritise smart policy and support in this new era," he said.

Australian Associated Press