"Despite public support for a net zero target, there is currently no national plan for transitioning to renewable energy (a backdrop for the very low rating for the National Climate Policy indicator), with the policy uncertainty undermining investment and causing energy supply concerns," the report stated.
"The country's lack of domestic ambition and action has made its way to the international stage."
Australia settled poorly across categories of greenhouse gas emissions, renewable energy, energy use and climate policy.
The only nation to score zero on the global policy index, Australia dipped four spots overall from the previous year when it was ranked 50th.
"The country’s lack of ambition and action has made its way to the international stage," the report says.
"Australia has fallen behind its allies and its inaction even attracted public criticism in the run-up to COP26."
The Morrison government announced this week a $250 million Future Fuels investment into the expansion of public electric vehicle charging and household smart charging.
Get the latest breaking news from SCA newsrooms around Australia. Short, simple and everything you need to know.