Australia's car market will meet new rules to cut emissions for three years even if manufacturers make no changes to vehicles, according to new modelling.
The Electric Vehicle Council made the finding after analysing data from the latest S&P Global Mobility forecast and found that rather than making big changes to the industry, the federal government's proposed vehicle standard could be "too weak".
But the lobby group representing car brands, the Federal Chamber of Automotive Industries, rejected the claim and said its own analysis found the New Vehicle Efficiency Standard could result in price hikes for popular models.
The findings come as the federal government considers public submissions into its preferred fuel-efficiency standard that is expected to be introduced next January.
The standard, like those in countries including the US, UK, Japan and China, will set emissions limits on vehicle fleets and will be designed to encourage car makers to sell more low-emission models to balance sales of high-polluting vehicles.
The government's preferred standard, which would cut emissions by more than 60 per cent between 2025 and 2029, was criticised by the chamber for setting "extremely aggressive targets" at short notice.
But the Electric Vehicle Council's analysis of S&P Global's vehicle forecast for the Australian market found existing passenger vehicles would meet the proposed carbon emissions targets in 2025, 2026 and 2027 without changes.
The modelling showed light commercial vehicles, such as utes and vans, would also meet the standard in 2025 and 2026, and the car market would have sufficient "credits" from passenger cars to offset additional emissions in 2027 and 2028.
Car manufacturers would have to launch more efficient vehicles by 2029, the figures showed, when "a small gap" emerged between the emission cuts and available credits.
Figures from the S&P forecast were based on the entire Australian market, however, and did not analyse the fleets of individual car brands.
But Electric Vehicle Council chief executive Behyad Jafari said the data proved Australia's proposed fuel-efficiency standard would not force manufacturers to make swift and radical changes to the cars they sold.
"It shows the government's efficiency standards are actually probably too weak in the early years to force a change from what's happening anyway," he said.
"The reality is that 'option b' New Vehicle Efficiency Standards won't actually push the market to significantly change what it was already going to do."
Mr Jafari said the council supported the government's proposal as having a fuel-efficiency standard would "lock in" emission limits and send a "long-term signal" to automakers that Australia would not accept inefficient cars.
Australia's peak car lobby argued against the proposed fuel standards in its public submission, however, calling the government's target "extremely aggressive" and arguing that it would "cause significant disruption" and "higher retail prices".
A chember spokesman rejected the council's claims that the standard could be met for years without changes and called for lower targets introduced more slowly.
"The (chamber) has consistently advocated for a balanced and realistic (fuel-efficiency standard) that accommodates Australian consumer vehicle preferences, does not result in new vehicle price increases, and achieves meaningful emissions reduction," he said.
"We do not believe the government’s preferred (New Vehicle Efficiency Standard) proposal achieves any of these objectives and stand by our analysis."