It also shows the extent to which the government will have to compensate low-income households if it pushes ahead with proposals to raise the GST to ensure any tax hike is not regressive.

New modelling from the Parliamentary Library reveals the likely impact on government revenue and household budgets of an increase in the GST to 12.5 per cent, or a broadening of the current 10 per cent GST base.

It shows the government would raise about $14 billion a year by broadening the GST base or raising the rate to 12.5 per cent.

It estimates a carbon price of $28 per tonne would raise the same amount.

The modelling also shows if the GST base was broadened it would cost the average household about $48 a week, and if the rate was raised to 12.5 per cent it would cost households less, at $23 a week.

But a carbon price of $28 per tonne would cost households less than both options – just $10-15 a week on average – while raising the same amount of revenue for the government, it shows.

The modelling is in gross revenue estimates – it shows how much revenue a higher GST and carbon price would raise, including revenue from the sale of carbon permits, before given any consideration to compensation packages for households.

The analysis, which was commissioned by the Australian Greens, comes after the Australian Council of Social Service (ACOSS) released modelling this week showing the current 10 per cent GST consumes 13.4 per cent of disposable income for those in the bottom fifth of households, which would rise to more than 20 per cent if the rate were lifted to 15 per cent, as is favoured by some within the Coalition government.

The ACOSS modelling, carried out by the respected National Centre for Social and Economic Modelling (NATSEM), went a long way to explaining Labor's trenchant opposition to any GST increase and suggested that any compensation built in to ensure the poorest are left "no worse off" – as the Prime Minister has pledged – will require an enormous "churn".

Greens Treasury spokesman, Adam Bandt, said the modelling shows that "dollar for dollar," it would be fairer to bring back the carbon price than to lift the GST, and it would cut pollution as well.

"This research exposes the Alice in Wonderland logic of the Liberals, where a price on pollution is a great big new tax that will wipe cities off the map, but a new tax on almost everything we buy is a fair and reasoned proposition," Mr Bandt said.

"Treasurer Scott Morrison's vague suggestion of compensation [for a GST increase] misses the point. If a higher GST demands much more compensation than a carbon price but both can raise about the same amount of gross additional revenue, it must be better and fairer to go with the carbon price, especially as it will also cut pollution."

The Turnbull government has not said it plans to raise the GST, but is considering it in the context of a broad re-arranging of tax rates and spending.

The Parliamentary Library modelling relies on the 2013-14 budget papers, when Treasury lowered its carbon price estimates for 2015-16 and 2016-17.

The carbon price as legislated provided for a fixed carbon price in 2012-13 of $23 per tonne, rising to $24.15 in 2013-14 and $25.40 in 2014-15 before moving to a 'floating' price that included linkage to the EU emissions trading system.

An earlier version of this story said the modelling was done by the Parliamentary Budget Office. It was Parliamentary Library modelling.