The Combined Pensioners and Superannuants Association (CPSA) held a candidate forum on Thursday, attended by all six candidates - Kate Hook, Stacey Whittaker, Kay Nankervis, Sarah Elliott, Andrew Gee and Adam Jannis.

The schedule included questions from the floor.

The first audience question to be directed at all six candidates was on the topic of climate change, with the voter laying out his concerns for the future, such as an increase in extreme weather events and parts of the country and the world becoming uninhabitable.

He said: "I think a vote for politicians and political parties encouraging and facilitating more fossil fuels is a vote for civilisation collapse. Why should I vote one for you?"

No candidate denied the existence of climate change, but they had different views on how to address the issue.

The Greens' Ms Nankervis, laid out the most ambitious targets, which includes net zero or net negative emissions by 2035.

"Both the major parties do not have sufficient targets to deal with this existential problem facing humanity. The Greens do," she said.

"... Approaching net zero by 2050 is not strong enough."

Kate Hook, an independent, said climate was her number one priority and her "whole reason for running".

She said the target of net zero emissions by 2050 did not go far enough and called the 2020-30 decade the most critical for responding to climate change.

"I would support the only credible climate bill that's on the table at the moment, from an independent, Zali Steggall, because it is ambitious, and the rest of the world is asking us to be ambitious," Ms Hook said.

Ms Steggall wants to cut emissions by at least 60 per cent by 2030.

The Coalition and Labor have committed to net zero by 2050, and Labor's Ms Elliott stood by the target.

"In an ideal world, we would really like to be able to shut off coal, shut off gas, but at this point in time we are still in transition," she said.

"... Don't completely rule out Labor as not supporting climate change. We do. We have a really strong history of supporting climate change measures, but we do need to be realistic about it."

Mr Gee was also hesitant about setting more ambitious targets, but noted he did support net zero by 2050 and wanted rural and regional Australia to be part of the planning.

Mrs Whittaker, the One Nation candidate, described herself as "a strong believer in climate change", but went on to say that renewables are "not effective enough" to rely on entirely.

"We need to ensure that we have effective, reliable energy. That's why One Nation are strong supporters of keeping coal open," she said.

The United Australia Party candidate, Mr Jannis, meanwhile raised concerns about potential mass job losses for people working in coal mining if Australia rapidly switched to renewables.

"These jobs aren't there to replace the good quality, long-term, sustainable jobs from operations like mining," he said.

The Federal election will be held on May 21.