Last Tuesday night, Tony Abbott was in his element. Surrounded by climate change sceptics and deniers he set about destroying Malcolm Turnbull’s signature energy policy. And he did so with panache, his opening line more a battle cry: “It takes character to do what’s right and it takes courage to disagree with your peers.”

Abbott was referring to Bob Carter, the late professor of geology who rejected the scientific consensus that climate change was being exacerbated by human activity, principally the massive production of carbon dioxide and other “greenhouse gases”. The former prime minister quoted Carter as saying, “Science does not operate by consensus … it is often best progressed by mavericks.” It was in no small way a metaphor for what Abbott was up to in this provocative speech. He was going out of his way to publicly disagree with his peers in the parliamentary Liberal Party and was progressing his own maverick campaign to destroy Turnbull’s credibility, but for a noble cause. “Far from wrecking the government,” Abbott claimed, he and other coal champions in the Coalition were trying to “save it”.

It was a masterclass in undermining and made Anthony Albanese’s effort two weeks prior look like a glowing endorsement of his leader Bill Shorten. To get what “Albo” was up to you had to read between the lines. Know the context. You had to take his call for Labor to “maintain a strong relationship with business” as pejorative. You had to interpret that it was a deliberate rejection of Shorten’s divisive attacks on the top end of town and therefore a subtle plea to his colleagues to reject Shorten himself.

Albo was about “plausible deniability”; Abbott was about a demolition job. But both politicians had chosen the timing of their pitches carefully, intending to do damage to their leaders’ prospects of scoring convincing wins in the impending July 28 byelections. A couple of losses would suit them just fine, for it would galvanise doubts about Turnbull’s and Shorten’s ability to fight and win the general election.

Losses would give impetus to the need for “conversations” about alternatives. Indeed, on Monday, Abbott raised the prospect of being leader again some time in the future during an interview with Radio 2GB. Although, he said, unlike Turnbull, he does not believe in bringing down a democratically elected prime minister.

“No one is taking him seriously anymore,” was the reaction of a key Turnbull adviser. “He’s delusional,” was the assessment of one Liberal MP. But Abbott’s status as a former prime minister and support from sections of the conservative media mean that his disruptive tactics are noticed and unhelpful to say the very least.

Abbott is calling on Turnbull to follow Donald Trump and pull out of the Paris emissions reduction commitments. He now claims he thought these were merely aspirations when he signed up to them.

This sideswipe comes at the end of a very good couple of weeks for the Turnbull government. First its entire income tax package passed, then came Shorten’s misfire over his company tax policy. But by highlighting Coalition divisions over energy policy once again, Abbott has put the focus squarely back on the very malaise that contributed to 35 losing Newspolls in a row – a new record set earlier this week.

The fact is there are real concerns in the government around the national energy guarantee (NEG). The Australian reported that the Nationals had prepared a two-page list of demands to encourage the building of new base-load coal-fired power stations. This plan is to supplement the prime minister’s signature policy and comes with a price tag of $5 billion proposing a “government-owned company model”.

The only trouble is the deputy prime minister and Nationals leader, Michael McCormack, hasn’t seen the draft “party policy”. No doubt it’s the work of Monash Forum members George Christensen and Barnaby Joyce, guessed one exasperated government insider, but there are others in the party of the same mind. McCormack came to the defence of Turnbull, saying, “We have a positive plan on the table with the national energy guarantee, which is supported by the Liberals and Nationals government.” He says it is a plan that can “deliver reliable energy supply while lowering costs and reducing emissions to meet set targets”.

Oh no it can’t, according to Abbott. And the main block to that ambition, he says, is the commitment to emission reduction by promoting renewables at the expense of cheap, reliable coal. Except of course that new coal-fired power plants – euphemistically dubbed high intensity and low emissions – are enormously more expensive than renewables with battery back-up.

Abbott says the government is “kidding us” by wanting to continue emission reduction targets that have seen energy costs rise since he scrapped the carbon tax: “Isn’t one of the definitions of insanity doing the same thing and expecting a different result?” He claims there is no plausible evidence you can provide cheap, reliable energy and reduce emissions. Turnbull disputes this, citing Energy Security Board analysis that the NEG will reduce prices by 23 per cent up to 2030.

Abbott is calling on Turnbull to follow Donald Trump and pull out of the Paris emissions reduction commitments. He now claims he thought these were merely aspirations when he signed up to them. “Absent America,” he added, “my government would not have signed up to the Paris treaty.” That drew a swift rebuke from Foreign Minister Julie Bishop, who was Australia’s chief negotiator in Paris. “When we signed up … it was in the full knowledge it would be an agreement Australia would be held to account for, and it wasn’t an aspiration it was a commitment,” she said. Unlike Trump, “Australia plays by the rules – if we sign an agreement, we stick to that agreement”.

Abbott of course, like Trump, rejects the science of climate change. He once famously described it as “crap”. And ominously for Turnbull he accuses the PM of wanting to do another deal with Labor as he did in 2009, a move that led to Turnbull being dumped as then Opposition leader and the ascent of Abbott himself. Shorten says his fear is that the NEG is “in danger of becoming a watered-down compromise between two wings of the warring Liberal Party”. He says you get the impression Turnbull will want to make the problem go away “by placating the right wing of the Liberal Party”. If he does, the chance of reaching agreement with the Labor states, or gaining the support of Labor in parliament to offset Abbott, Joyce and others abstaining or crossing the floor, will be dashed.

Just how much damage this flaring of the energy wars could inflict on the government ahead of the byelections is hard to gauge. Shorten hopes it will be a blow – or at least enough for him to hold on to Braddon in Tasmania and Longman in Queensland. Failure in either seat, or both, has been flagged as a benchmark to judge the Opposition leader’s viability as a winner. According to one insider, a “small cabal” in Labor caucus was trying to create a leadership stampede in the past fortnight. Evidence for this, he says, was the quick leaking of a “captain’s pick” version of Shorten’s gaffe over the extent of company tax cut rollback. Anthony Albanese, for one, will be watching very closely as Super Saturday approaches.

But as in all oppositions there is fretting over Shorten’s widening unpopularity gap in the Newspoll, while Turnbull’s has been narrowing dramatically. These indicators, as with preferred prime minister, are not considered predictors of an election result like the two-party-preferred measure, but they can spook a party room. And they come at a time when Liberal research in Victoria is finding growing support for Turnbull and the party there. It’s a claim supported in the Newspoll and Essential, which both show nationally the Liberal–National primary vote is at 40 per cent. It doesn’t take much to link Labor’s decline to Shorten’s unpopularity.

A more benign view for Shorten could also attribute the government’s better performance to the fact that Abbott and his mates have been relatively quiet in recent weeks. Until now. Whatever the reason, few believe Shorten who, to quote one of his allies, “has worked his guts out”, would not fight to retain his job.

This alone should give pause to those thinking of bringing down the Opposition leader. The transactional costs of a bloody coup are still being paid by Turnbull, even though he has won an election in his own right. And they were certainly paid by Julia Gillard after she toppled Kevin Rudd. The only way to do it with minimal cost is to follow the example of the state Liberals in New South Wales. Premiers Barry O’Farrell and Mike Baird did their governments the huge favour of quitting parliament. A more pertinent example is former Victorian premier Ted Baillieu. He was rolled without a vote and left parliament at the next election.

Abbott’s antics this week may help Shorten snare the wins he needs to bolster leadership. The pressure then would be back on Turnbull, and that no doubt was Abbott’s plan all along.