"Dumping" the carbon tax – the fixed price period of Australia's carbon pricing scheme – makes for a handy headline. But it would be much harder for a Rudd government to actually do.

That's why the Gillard government didn't do it some time back when cabinet examined this option in detail.

To start with, it would require legislation, which can't happen before the election since the parliament has risen and which the Greens leader, Senator Christine Milne – alive for an opportunity for pre-election product differentiation – was quick to say she would not support.

That would leave a Rudd government, if re-elected, seeking support from the Coalition to change the carbon pricing legislation Tony Abbott has built his entire political persona on promising to repeal.

Also, the current legislation requires that, before the shift from a fixed price to a floating price can occur as planned in July 2015, the new Climate Change Authority must set an annual cap on pollution based on its assessment of what Australia's emissions reduction target should be.

The authority releases a draft report in October and a final report in February 2014 before announcing the first five years of annual caps in May.

That means if a Rudd government really hurried, the earliest it could feasibly start a floating price under the current arrangements would be July 2014 – one year before the price is set to float anyway.

That would probably mean Australia's price dipped to a lower international price at that time because when the price floats the Australian scheme is linked with the European Union scheme, where the price is currently around $6 a tonne, compared with Australia's price of $23, rising to $24.15 next week. It would be a good outcome for business, but not for the budget, which would be down by several billion dollars worth of carbon permit revenue, unless Rudd also managed to wind back legislated compensation.

Interestingly, some climate lobby groups are not adverse to the idea of bringing the floating price forward because the climate authority is likely to highlight the fact that the international community is taking action and Australia's target – and the annual emission reduction caps that will get us there – should be tougher than the current 5% by 2020 minimum that both major parties say they support.

"We are not opposed to that happening, but it has to be based on the Climate Authority's view," said the chief executive of The Climate Institute, John Connor.

"With China implementing an emissions trading scheme and US President Barack Obama chucking the regulatory kitchen sink at this issue, it would highlight that international action is indeed underway and it may make the necessary ambition for Australia more cost competitive to achieve."

Business groups are also keen for Labor to consider any mechanism that would allow the floating price to reduce carbon permit costs as soon as possible.

But Milne strongly warned Rudd against the idea, saying it would "create huge uncertainty" and undermine the scheme hammered out between Julia Gillard, the Greens and the crossbench independents.

The new treasurer, Chris Bowen, will meet major business groups next week, which are united in their support for the idea of bringing forward the shift to a floating price – at least while the international price remains low.

But it would also be very difficult for Rudd to change the pricing mechanism in the middle of a financial year because of the way free permits are allocated to emission intensive industry.

The climate change authority includes former reserve bank head Bernie Fraser, Prof Ian Chubb and former Australian Industry Group head Heather Ridout.

As well as assessing international action against which Australia's efforts should be compared, it will look at the costs of the impacts of climate change that Australia is already feeling.

The Coalition would abolish the authority and repeal the carbon tax. Unless it wins a majority in the Senate, that is also likely to run into problems in the upper house.