Track-free trams? Yes, that's what they're calling them. And the Inner West Council is pushing the idea as a solution to the transport woes of the Parramatta Road.

In fact, four councils in Sydney's inner west are supporting the notion, which they see as a potential "game changing" public transport option to be introduced concurrently with the WestConnex motorway.

"There have been more than a dozen plans to transform Parramatta Road over the years - and they have all failed due the lack of commitment to a real public transport solution," said the administrator of the Inner West Council, Richard Pearson.

Under the $200 million plan, released on Tuesday by Mr Pearson's council, the electric trams - operating on battery power rather than power lines - would run down the middle of Parramatta Road, carrying people between Strathfield and the city.

The trigger for the Inner West study was the WestConnex motorway, which the state government said would remove traffic from Parramatta Road and civilise it for more residential and community uses.

But the state government has failed to settle on its own transport plan for Parramatta Road. And with the clock ticking towards the completion of the $16.8 billion motorway in 2023, the Inner West Council is keen for a public transport option that could be open before the motorway's completion.

"Parramatta Road should change from being a thoroughfare to a high street - with shopping, dining, and a good living environment," Mr Pearson said.

One advantage of the track-free tram idea is that it could be implemented relatively quickly. It would also be cheaper than light rail, and have the key engineering advantage of being able to run on a relatively narrow strip on the middle of the existing road.

This would allow kerb-side lanes to be freed for parking or other uses.

Ken Welsh, the council's strategic transport planner, said the trams could use a narrower lane than buses because they were equipped with optical guidance technology, similar to that used in luxury cars, which enabled them to stay within the lane.

"There is still a driver, but they mostly control speed, and they don't have to worry about horizontal wobbling."

Mr Welsh said trams had the added benefit of having a "much lower" carbon footprint than diesel buses.

While this would be the first system of its kind in Australia, track-free trams are used in a number of European cities, including Barcelona, Geneva and Luxembourg.

Former Mayor of Leichhardt Darcy Byrne, who initiated the study before the council was amalgamated in May last year, welcomed the findings, alongside mayors from Burwood, Canada Bay and Strathfield councils.

"What we don't need is another good idea gathering dust - there is a narrow window to transform Parramatta Road or it will be a basket case forever," My Byrne said.

The plan is still in a conceptual stage, but the Inner West Council has pledged $80,000 towards a feasibility study in a bid to entice the Berejiklian government to back the proposal and co-sponsor the study.