The foreign minister, who will depart for Lima, Peru, for fresh United Nations climate talks in days, said it is an "obvious conclusion" that to bring down emissions Australia had to embrace nuclear energy.

Environment Minister Greg Hunt said on Sunday that although nuclear power was not Coalition policy, he was supportive of a debate but any shift would require bipartisan support.

Economist Ross Garnaut told Fairfax Media that Ms Bishop's suggestion that Australia should look at all sources of low emissions energy on their merits was a welcome one because avoiding dangerous climate change would require contributions from many sources.

"To arbitrarily limit the sources of low-emissions energy that we are prepared to consider may be to increase the cost of avoiding dangerous climate change and therefore to reduce the chances of our meeting the objectives that have been agreed by the international community," he said.

"Obviously, nuclear weapons proliferation must be avoided and costs of nuclear energy must take into account safe waste disposal."

Professor Garnaut added that nuclear energy would have to be assessed on its economic merits and ability to compete with other forms of power, including renewables and fossil fuels with carbon capture and storage.

He said nuclear power would become increasingly important in China and India and that Australia, with unusually rich endowments of all sources of energy, was likely to export those energies with the lowest international transport costs and keep those with the highest international transport costs for use at home.

"The economics are likely to suggest uranium enrichment – based on low cost renewable energy plus storage – before nuclear power generation in Australia," Professor Garnaut said.

The Labor MP Alannah MacTiernan said she'd been anti-uranium mining until her "conversion" in 2010. She said while she didn't think nuclear would ever be necessary in Australia, she was keen to see uranium mining expand in her home state of Western Australia.

"Nuclear has nowhere near the risks of spewing coal into the atmosphere," she said.

"But I personally don't see there's any point [to nuclear] when we have so much gas and renewable energy," she said.

Economist Dr Frank Jotzo from the ANU praised Ms Bishop's comments and said they were evidence of "mounting pressure on the Australian government to make some positives contribution to the international climate policy discussion".

He said while nuclear was feasible in the long term, the more immediate contribution Australia could make in lowering global greenhouse gas emissions was by exporting uranium to countries already using nuclear. Dr Jotzo said Australia's three main energy options were renewables, nuclear and coal and gas using carbon capture and storage.

"At this point time renewable are cheaper, however, as you move to a carbon-free electricity sector we need to push much further in the expansion of renewable energy sources and depending on the costs of both a mix of renewable and nuclear could be a cost-effective option in the future," he said.

It came as new polling for the clean energy industry showed voters want Australia to adopt more ambitious policies for renewable energy.

A survey of 1442 people commissioned by Solar Citizens, and conducted by the Australian Institute, found 76 per cent of people were either supportive or very supportive of increasing Australia's renewable energy target, rather than scaling it back.

Thirty-five per cent favoured increasing the target to 50 per cent by 2030, while a further 30 per cent wanted a target greater than 50 per cent by 2030.