Zali Steggall has promised not to direct preferences to other candidates and says the government should be more ambitious on emissions reduction than Labor as she makes her pitch to replace Tony Abbott in Warringah.

The independent candidate told Guardian Australia that Abbott had “continually denied climate change” and the conversation had “moved on” from carbon pricing because renewables were already cheaper than coal.

Steggall’s candidacy was welcomed on Monday by Labor and the independent MP for Wentworth, Kerryn Phelps, who said people were “disillusioned by the performance of the Liberal party” on issues including climate change and marriage equality.

Abbott holds Warringah with a primary vote of 51.65% and a two-party preferred vote of 61.55% but is being challenged by independents including Steggall, who is a lawyer and former Olympic skier, the Indigenous broadcaster Susan Moylan-Coombs and Alice Thompson, a former employee of the former prime minister Malcolm Turnbull.

The dumping of Turnbull in August has caused MP Julia Banks to join the crossbench and has been a major hit to the Coalition’s vote in progressive Liberal seats such as Kooyong, where a high-profile independent is also expected to enter the field.

The Herald Sun has reported that Banks is considering moving from her marginal seat of Chisholm to take on the health minister, Greg Hunt, in Flinders.

On Monday Steggall said Warringah was a “a very savvy electorate” and “as an independent it’s important to let people make up own mind” about their preferences.

Asked if failing to direct preferences might help Abbott retain the seat, Steggall replied that “a broad part of my base are moderate Liberal supporters”.

“We’re asking voters to think carefully about how they vote and I’m asking for people’s first preference,” she said. “To succeed, we need to bring down the primary vote of the current member.”

Asked about carbon pricing, Steggall said that a multi-pronged approach was needed to fight climate change and the conversation had “moved on” because there was “no need for subsidies” now that renewables were cheaper than coal power.

“We need to set ambitious targets to accelerate the transition to clean energy and the orderly retirement of coal,” she said. “Abbott and politicians on the far right are proposing subsidising coal, to keep open something that is not cost effective.”

Steggall said she would release a full climate policy before the election but pointed to more ambitious state targets as evidence of a “clear disconnect”, where “the federal government hasn’t been hearing people’s desire to make a difference”.

Steggall said that Labor’s emissions reduction target for electricity of 45% by 2030 was “a start” but was “not enough – we need to push for more”.

The Australian has reported that Abbott will write to voters that he has “more to do” for the electorate and “no one can fight harder for you and for our area than someone with the big megaphone that only a former PM has”.

“My other pledge is to do everything I humanly can to protect you from Labor’s tax attack that will unfairly target people in Warringah with above-average incomes and assets,” he reportedly says.

Steggall expects to capitalise on grassroots organising against Abbott from local groups including Think Twice Warringah and Voices of Warringah, which she said sprung up due to “growing dissent and dissatisfaction” particularly at “the way the Liberal party conducted itself last year”.

Steggall said that Abbott – who has suggested climate change is “probably doing good” – had “continually denied climate change despite all the facts being in”.

“It’s a fair assessment to say that he’s unwilling or unable to move and not open to debate or discussion,” she said. “He’s entitled to take that far-right view but it doesn’t reflect where this electorate is at.

“Warringah wants safe, sound and stable economic policy, but it’s a caring progressive electorate.”

Labor frontbencher Andrew Leigh told Sky News the opposition would “absolutely” still contest Warringah, describing the party’s candidate, Dean Harris, a small business owner, as “a great local bloke”.

The Labor leader, Bill Shorten, said that Abbott was a “formidable and tough campaigner” who could not be written off in Warringah.

He told reporters in Melbourne that Steggall’s nomination showed the government was “lurching from crisis to crisis” as their own supporters were running against the Liberal party as independents.

“On climate change … we agree that Tony Abbott has been a block on action on climate change – but it’s not just him, it’s the whole government.”

When asked about the potential for preferencing Steggall at the election, Shorten said: “This is an independent, she’s just announced that she’s running yesterday. We’ll examine her policies.”

Phelps told Sky News she was “very very pleased” that Steggall had decided to stand as an independent because voters were “angry about a lot of the mismanagement they’re seeing”.

“What we need to see are more independents from the sensible centre who can be an antidote to the lurch to the right we’re seeing from the Liberal party and Coalition government.”