New tests by Australia's peak motoring body show consumers are not receiving accurate information about many cars' fuel consumption or environmental performances.
Eight out of 21 cars tested in the latest tranche of the AAA's Real-World Testing Program recorded fuel consumption levels between 6% and 31% higher than in their laboratory test results.
AAA Managing Director Michael Bradley said the $14 million testing program is showing that on-road fuel consumption and tailpipe emissions can differ substantially from the laboratory test results displayed on mandated point-of-sale windshield stickers.
"In our latest batch of results, there is a 44 per cent spread in the gap between the tested cars' fuel consumption lab results and their on-road performance," he said.
"One 1.2-litre vehicle had similar on-road fuel consumption to several 2-litre cars, and a hybrid SUV had higher petrol consumption than a similar-sized conventional SUV.
"These tests show that when comparing vehicles, consumers and fleets cannot assume that vehicle performance as assessed by mandatory lab tests will translate into real-world savings or emissions reduction.
The Real-World Testing Program compares vehicles' fuel consumption and emissions in Australian driving conditions with the mandated laboratory test results reported by car manufacturers. It is run by the AAA and funded by the Commonwealth.
The third tranche of results released today covers a mix of SUVs, passenger cars and utes. Among the 21 vehicles tested, 11 delivered fuel consumption within 5% of lab test results, while eight exceeded their lab test fuel consumption by 6% or more. Two vehicles had on-road fuel consumption 10% to 13% lower than their lab results.
Six vehicles' on-road emissions exceeded current or future Australian regulatory lab limits for tailpipe emissions. Three exceeded the lab limits for oxides of nitrogen (NOx); one had on-road carbon monoxide emissions that were more than double the regulated lab test limit; and two exceeded the future limit for particle number emissions, to be introduced in December 2025.
Mr Bradley said: "Households and fleets looking to buy new cars can use Real-World Testing results to manage their transport costs.
"Our Program is also helping address greenwashing concerns and can make the Government's New Vehicle Efficiency Standard more robust and more effective."
Prime Minister Anthony Albanese launched the program last October.
Mr Bradley said: "The AAA is pleased to be partnering with the Government to deliver this important program and is grateful that it enjoys bipartisan political support.
"Real-World Testing will drive down demand for models that over-promise and under-deliver.
"Using these fuel consumption test results will improve motoring affordability for Australians, while cleaning up our light vehicle fleet.
"It also helps fleet-owners manage their purchasing decisions, budgets, and environmental commitments, while helping larger fleets save thousands of dollars a year."
Program testing is conducted in and around Geelong. It complies with strict guidelines that are based on European Union legislation and were developed in consultation with Australian regulators and industry.
Strict test protocols ensure fuel consumption and emissions results are repeatable and minimise the influence of human factors such as driving style and changing traffic flows. For research purposes, the AAA undertook 23 tests on the Program's reference vehicle (a Toyota RAV4), with fuel consumption across these tests having less than 2.5 per cent variability.
The four-year program will test 200 cars, SUVs, and utes, including electric vehicles. EV testing protocols are now being developed.
The AAA first proposed an Australian-specific Real-World Testing Program in the wake of the 2015 Volkswagen emissions scandal, which showed that emissions regulations around the world were incentivising carmakers to optimise their vehicles' fuel consumption and emissions performance for the laboratory tests being used for regulatory compliance.
Since then, international studies have highlighted large gaps between laboratory and real-world performance of new vehicles.
