AUSTRALIA's 20 per cent renewable energy target has helped spark $18.5 billion in new clean energy investment since its inception - and will drive another $8.8 billion to 2030 - an economic analysis commissioned by the industry's peak body has found.

The modelling to be released today by the Clean Energy Council also says Australia would have failed to meet its greenhouse gas targets under the United Nations Kyoto Protocol without the target in place.

Modelling indicates Australia's carbon emission are 20 million tonnes lower than they would have been without the renewables target.

The modelling - carried out by firm Sinclair Knight Merz - comes on the eve of a discussion paper to be released by Australia's Climate Change Authority as part of its review into the role and performance of the renewable energy target.

The target mandates that 20 per cent of Australia's energy is to come from renewables by 2020.