Experts say electric vehicle taxes will put Australia even further behind in the market.

Both Victoria and South Australia are planning to impose electric vehicle taxes to make sure that all road users contribute to road costs.

But both states also want to reach net-zero greenhouse gas emissions by 2050.

A new report from the University of Queensland says the taxes will put the greater goals at risk.

Researchers have issued a preliminary report, yet to be peer-reviewed, which finds that the proposed 2.5 cent-per-kilometre taxes will see electric vehicles (EVs) make up just 30 to 40 per cent of new vehicle sales in those states by 2050.

EVs are on track to account for around half of all new cars sold in Australia by 2035 and 65 per cent by 2050.

“In the worst case scenario ...[electric vehicles will make up] no more than 30 per cent of new car sales by mid century, which is ridiculous,” says University of Queensland E-Mobility Fellow Jake Whitehead.

“We're just being pushed further and further into the wilderness,” he told the ABC.

Dr Whitehead says Australia needs significant incentives can Australia to reach a 100 per cent electric vehicle market in line with a net-zero emissions target by 2050.

“Our early modelling suggests that the proposed 2.5 cent-per-kilometre EV road taxes could result in a 2050 sales rate that is at least 25 per cent lower than business as usual,” he said.

“Only the best-case scenario gets us [to 100 per cent EVs] — that's not the central scenarios, that's the best case scenarios.

“What I'm really concerned about is state governments continuing to use that [net-zero] rhetoric but then not backing it up with action.”

The study found that the greatest uptake of EVs would come from exempting EV drivers from existing road taxes or by offering monetary credit for electricity costs.

EVs accounted for 2.6 per cent of all new car sales worldwide in 2019, but just 0.6 per cent of new car sales in Australia.