The federal parliament is being urged to prioritise and pass the Albanese government's "electric car discount" in the final sitting weeks of this year, which would reduce the cost of some of the most popular zero and low-emissions vehicles by thousands of dollars.
A Labor election promise, the legislation could make popular models, such as the Nissan Leaf, up to $2,000 cheaper for some individuals and $9,000 cheaper for employers who run fleets.
However, the bill remains stuck in the Senate and some in the automotive sector warn further delays until next year would slow the take-up of low or zero-emissions cars.
"Certainty is king in this industry and time is of the essence," Federal Chamber of Automotive Industries' Tony Weber said.
"The quicker you can reduce CO2 from the cars on the road, the better. New cars stay in the car park, on average, for 21 years."
Meanwhile, the federal government has a busy final three weeks of sittings, where it will also be trying to pass contentious workplace relations laws and a national anti-corruption commission as a priority before Christmas.
To get the electric vehicle bill through the Senate, it has to negotiate with the Greens and crossbenchers, because the Coalition is opposed to the bill.
However, Greens leader Adam Bandt and ACT Senator David Pocock are calling for plug-in hybrids to be removed from the legislation, because the vehicles have internal combustion engines.
They argue that only zero-emissions — not low-emissions — vehicles should benefit from the discount.
"This is friends talking to friends in this case," Behyad Jafari from the Electric Vehicle Council said.
"[Labor, Greens and Senator Pocock] all agree on the need to make electric cars cheaper and get more on the road.
"The most important thing is this bill passes this year.
"Hopefully, they will clear some time in their diaries and hash out the thing and get it done."
Mr Weber said a shortage of electric cars, globally, meant hybrids could play an important role in Australia.
"It would be a retrograde step to reduce the options further in this bill," he added.
Government does not intend to budge
The government does not want to remove plug-in hybrids from its bill and does not expect the crossbench to kill legislation that it largely agrees with.
Labor argues plug-in hybrid cars will help ease "range anxiety" among some people in regional areas.
The legislation is intended to be backdated to July 1 this year and will be reviewed in three years, when plug-in hybrids could be removed from the scheme.
However, ACT's Senator Pocock — who could be a decisive vote — is still not convinced.
"I will struggle to support a bill that uses taxpayer money to subsidise superseded technology," he said.
"This bill is designed to increase uptake of EVs as fleet vehicles, which will help create a bigger second-hand EV market in a few years' time.
"That's what it should do, and can do, without subsidising PHEVs to the tune of $1 billion over the next decade.
"That $1 billion can be much better spent and strategically targeted."
The Greens have a similar view but, in a statement, a spokesperson said the party would debate its position after negotiations with the government have concluded.
Fuel efficiency standards the bigger test for EVs
Part of the reason some electric vehicle advocates want the discount bill passed soon is so they can turn their attention to what they see as the far bigger issue: fuel efficiency standards.
Energy Minister Chris Bowen has made it clear that he's a fan of introducing them, releasing a discussion paper canvassing options in September.
Efficiency standards are put on the fleet of cars automotive manufacturers sell in a country.
The tougher they are, the more this encourages car-makers to sell additional electric or low-emissions options, increasing local supply and helping drive down the overall price.
"The much-bigger problem we have at the moment is supply," Mr Jafari said.
About 3 per cent of cars sold in Australia currently are electric, however that figure is unlikely to be a true reflection of demand, because the waiting lists for some EVs are very long.
"There are global supply constraints," Mr Jafari added.
"We aren't getting our fair share of electric cars because we don't have the same fuel efficiency standards as other comparable countries."
Some 80 per cent of the global car market already has fuel efficiency standards in place.
Previous discussions about the move in Australia has led to campaigns against the costs to consumers.