“This report is wrong and misleading and the organisation should correct the facts immediately,” Plibersek said.

“Under the Liberals and Nationals, on average, less than half of decisions made under national environment law have been on time. With Labor, that’s almost doubled with 86 per cent.”

The government has committed more than $200 million to beef up departmental resources to speed up project assessments.

While Australia’s clean energy shift ranks among the fastest in the world, the transition is falling short of the pace required for Australia to hit the government’s 82 per cent target.

However, the speed of the roll-out has been increasing, and the government insists its target remains within striking distance after a record year of clean energy investment. Data from the Clean Energy Regulator shows up to 7.5 gigawatts of renewable capacity will have been connected to the grid this year, eclipsing the 6 gigawatts of additional capacity per year experts say is needed to replace fossil fuel energy production.

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The Clean Energy Investor Group commissioned law firm Herbert, Smith and Freehills to assess time-frames under the EPBC Act.

Merzian said a chief gripe of energy developers was that state governments imposed environmental assessments alongside the federal government, causing unnecessary duplication.

“Inconsistent and inefficient regulatory processes are hindering the billions of dollars of investment needed for Australia’s clean energy transition,” Merzian said.

Federal governments have made promises about streamlining approvals by licensing state governments to administer the federal laws, but green groups warn this would lower standards and risk further environmental harm and the issue remains unresolved.

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