The coalition will have to spend billions more than it has allocated to meet its pollution reduction targets, new research has found.
Monash University's Centre of Policy Studies and The Climate Institute have released findings that show the coalition's Direct Action plan would actually see Australia's CO2 emissions increase.
The independent assessment, released on Thursday, states the coalition would have to spend between $4 and $15 billion extra by 2020 to achieve its promised cut to greenhouse gas emissions.
Opposition Leader Tony Abbott has pledged $3.2 billion over four years to fund activities that reduce carbon emissions, like revegetation and improving soil carbon.
Critics have questioned whether the coalition scheme can succeed given the level of funding, but the opposition says Direct Action will work.
Both Labor and the coalition have agreed to cut CO2 emissions by 5 per cent of 2000 levels by 2020, though environment groups say a target of at least 25 per cent is needed.
The Climate Institute's head John Connor said the coalition would struggle to turn the tide on CO2 pollution with the policy as it stands.
"Even with conservative assumptions, the coalition's policy as it is currently defined would see Australia's emissions rise about 9 per cent by 2020," he said in a statement.
The coalition could reduce domestic carbon pollution by 200 million tonnes by 2020 compared to 290 million tonnes under Labor's carbon laws, he added.
The analysis is part of the institute's pre-election "Pollute-o-Meter", which compares the effectiveness of government policies in slashing CO2 output.
In the 2010 federal election, the coalition fared better than the ALP.
The report made a number of recommendations for strengthening the coalition policy, including that they drop their pledge to review the bipartisan Renewable Energy Target (RET) in 2014.
Uncertainty in renewable energy and carbon policy was "hampering investment" in clean energy, it stated.
A report by carbon specialist firm RepuTex for the WWF earlier this week found repealing the carbon price - as pledged by the coalition - would likely lead to higher retail electricity prices.
