Clive Palmer's shock announcement on Wednesday night next to former vice president Al Gore has been very cautiously welcomed by Australia's environment movement.

Palmer's announcement effectively leaves Abbott completely isolated on climate policy, both domestically, and as Al Gore's presence demonstrates, internationally as well. It is remarkable that one of Australia's largest coal barons has firmly declared his support for renewables, taking action on global warming, and introducing an emissions trading scheme.

Senior leaders of some of the largest environment groups told me that they welcome Palmer's position on the renewable energy target, the Clean Energy Finance Corporation and the Climate Change Authority, while approaching the details with caution and a large grain of salt. It was labelled as "definitely surprising", "very smart politically", "surprising" and "courageous".

There are no details behind Palmer's announcement, and it is unclear what approach he will take with his decision to support the abolition of the carbon "tax" and its replacement with an emissions trading scheme. Palmer also stated that he would not support prime minister Abbott's "direct action" policy, criticising it as a waste of money.

Kelly O'Shanassy, the new CEO of the Australian Conservation Foundation, who is organising the Climate Reality project that Gore is in Australia for, said "keeping the 'clean three' of the RET, the CEFC, and the CCA is great news for all Australians. It's great to see that Clive Palmer has the courage to listen to the voices of Australians when they say they support clean energy and they support cutting pollution."

Several recent polls showed that a large majority of 72 percent of Australians support keeping or expanding the renewable energy target. Similarly, the polls show that Australians support putting a price on carbon, and just 22 percent support the discredited "direct action" policy.

The Clean Energy Council was effusive in its congratulations. Deputy Chief Executive Kane Thornton described the announcement as "a Titanic boost for the clean energy industry". Increasing the proportion of Australia's energy from renewable sources would mean lower costs for consumers and potentially thousands of extra jobs. Kane said in a statement, "what we need is policy stability to unlock these benefits, and the best outcome for the industry is if the policy is left alone to continue working."

A senior environment campaigner noted to me that "we are approaching Palmer's announcement with caution, especially on the RET. This is not the first time the Palmer United Party has made an announcement about renewables, only to see it reversed less than 24 hours later."

What is clear is that Tony Abbott's offensive against renewable energy and the Clean Energy Finance Corporation are effectively dead.

CEO of Environment Victoria, Mark Wakeham said to me, "Palmer's announcement is definitely surprising, but is a pretty productive intervention that will change climate politics in Australia. The government should now give up on its attack on the RET and the CEFC immediately."

Ben Pearson, the head of campaigning for Greenpeace Australia-Pacific agreed, saying to me: "if this position holds, Palmer has turned climate politics on its axis."

The most ambiguous part of Palmer's announcement related to his position on the carbon price. He has said he wants to abolish the carbon tax and replace it with an emissions trading scheme. The catch is that he doesn't want the ETS to kick in until our major trading partners have one.

I spoke to someone intimately involved in creating the architecture of the carbon price under Labor and asked them whether what Palmer was proposing was even possible. If Palmer votes to keep the architecture of the carbon price, by simply amending the existing legislation to set the price to zero dollars, and delays the automatic linkage of the carbon price to Europe's scheme, then it would be relatively simple to re-start Australia's emissions trading scheme in the future.

ACF's O'Shanassy said, "what the Palmer United Party has proposed around the carbon price is basically like taking the battery out of your car. The car still runs fine, and a smart person can always come along, replace the battery, and be off to the races."

However, I'm told it would become a "nightmare" if the entire carbon pricing framework was torn up and rewritten from scratch.

National campaign director for the Wilderness Society, Lyndon Schneiders, told me that "it's fantastic that Palmer is supporting an ETS and retaining the renewable energy target. It would be great to now see him to renounce his Galilee coal projects."

The CEO of The Climate Institute, John Connor, however, described the potential repeal of the carbon price as "ugly" and said it was unclear "whether the Palmer United Party's call for an emissions trading scheme is a pre-condition for repeal of the carbon price and exactly what is intended. The devil is in the detail."

This concern was held by several other eNGO leaders, who told me that they fear Palmer is more interested in creating a political bargaining chip, rather than having any real commitment to climate action.

The cautious welcome to Palmer's announcement extended beyond the environment movement.

I also spoke to several union leaders, and the opposition Labor party.

Colin Long, the Victorian secretary of the National Tertiary Education Union, a union that has been a strong advocate for climate action, told me that "Palmer's acknowledgement of the importance of dealing with climate change is significant, and the idea of an ETS is an improvement on Abbott's useless "direct action" corporate subsidy policy. Palmer's commitment to the renewable energy target and the CEFC is a great relief and will hopefully thwart the Coalition's attempt to destroy the renewable energy industry."

Long-standing carbon price supporter and national president of the union representing coal miners, Tony Maher of the CFMEU, told me, "our concern about abolishing the ETS was that it would mean we had to renegotiate all the consumer and job protections all over again in the future. It's not clear whether PUP is proposing to leave all those protections in place or not. We will be urging them to do so."

Federal Labor also welcomed Palmer's support for an emissions trading scheme. An opposition spokesman said, "Labor's position on climate change has not changed. We will not support the repeal of the carbon tax unless there is a credible alternative that will deliver meaningful action to tackle climate change."

It is clear that Palmer (and Gore) has completely rewritten climate politics in Australia. Why he has done this is not clear, and there are elements of incomprehensibility in what has said.

However, as a political tactic, it could potentially be a master stroke, and consigns Abbott's almost non-existent climate policy to the dust bin. As Greenpeace's Pearson quipped, "tonight Al Gore has delivered Tony Abbott an inconvenient senate."