Crowdfunding site Indiegogo has been criticised for carrying a campaign raising money for the Heartland Institute, a thinktank that casts doubt on climate science, to run a rival conference alongside a landmark UN summit in Paris in December.

The Pandemonium in Paris campaign will direct funding to a “counter-conference” attended by allied libertarian organisations, including the Cato Institute, the Committee for a Constructive Tomorrow and the Competitive Enterprise Institute.

Heartland’s vice president of external relations, James Taylor, made his pitch to donors thusly: “We need your help us stop [sic] the UN and the Obama administration from raising your taxes, increasing your energy costs, and destroying jobs.”

Charlie Kronick, senior climate advisor to Greenpeace UK, questioned Indiegogo’s facilitation of climate denial.

“Indiegogo are showing a truly courageous commitment to freedom of speech. They may not agree with what you say, but they will risk trashing their own brand to defend your right to say it,” he said.

But the crowdfunding platform said the Heartland campaign would not be taken down.

“Indiegogo is an open platform, and as such, we accept all campaigns other than those that aim to raise money for illegal activities or those that would harm or promote offenses against others,” said a spokeswoman.

Ethan Mollick of Wharton University, who has written extensively on crowdfunding said: “Indiegogo prides itself on accepting almost any campaign, Kickstarter is more likely to throw out campaigns.”

Indiegogo has twice drawn the line at raising legal fees for US police accused of killing suspects, citing breaches of its terms of use. These say that fundraisers “shall not make any false or misleading statements in connection with their campaigns”.

Prospective Heartland donors were told by Taylor that their funding would be used to “hold a series of media events with scientific experts explaining the compelling evidence that humans are not causing a global warming crisis.”

This contradicts an overwhelming scientific consensus – 97% of climate scientists agree the climate is warming and humans are causing it. Governments, a vast array of reputable scientific academies and even oil companies accept climate change as a fact.

But not the Heartland Institute, which tells you why the UN really wants to cut back on carbon emissions:

“The UN is attempting to impose binding carbon dioxide restrictions on the United States and transfer billions of dollars of climate ‘reparations’ from the United States to nations like Iran, North Korea, and Venezuela,” said Taylor.

There is no indication that the UN Green Climate Fund (GCF), the main mechanism for adminstering climate finance, plans to fund projects in any of these countries. The US government has pledged $3bn (£2bn) to the fund, but the climate sceptic Republican Congress have blocked the funds from being released.

Indiegogo’s terms also bar fundraisers from creating a campaign “to cause harm to people or property”. Heartland’s stated aim is to stop a globally binding deal being signed in Paris. The aim of the deal being prepared is to keep global warming within 2C. If it does not, the world’s most respected climate science body the Intergovernmental Panel on Climate Change has said every region of the world will be affected by destructive weather, aggravated resource conflicts and displaced populations. The burden, it says, will fall disproportionately on the poor.

“This campaign does not currently violate our terms of use,” said the spokeswoman.

The Heartland Institute has an annual budget of $6m and counts the Koch oil billionaire brothers among its backers. It has previously spent $100,000 on a classroom programme aimed at spreading doubt about climate science in US schools.

The Campaign against Climate Change protest outside the London offices of leading climate change deniers. Photograph: Peter Marshall / Demotix/Corbis

But on Wednesday the institute asked believers to stump up $60,000 to cover flights, hotel rooms and expenses for its attempt to derail the Paris talks. After two days, the site had raised $16,700. Donors include known climate sceptics from around the world. The largest donation of $10,000 came from a person identified as David Herro. Herro is a US hedge fund manager, who according to Politico, was one of the Republican Party’s 50 biggest donors in 2014 and has this year made hefty donations in support of GOP presidential hopefuls Marco Rubio and Chris Christie.

The news of the campaign was met with derision by green groups.

“So it has come to this,” said Kronick. “The denial industry once commanded the heights of Washington, writing policy in the White House and dictating negotiating strategies at the UN. But scientific reality has caught up with them. Now, like a third-tier Apprentice contestant who just got voted off the show, they’re scratching around for financial support for their failing business. The tide has turned and the deniers have been left stranded on the far bank, desperately updating their Indiegogo account to see if someone’s thrown them a buck.”

Heartland have long enjoyed the patronage of the world’s major oil companies. But one by one they have abandoned them. ExxonMobil, which has recently been exposed for its own obfuscation over climate science, said it was withdrawing its support for Heartland in 2008. Melinda Pierce, Sierra Club legislative director, said the campaign showed the institute was now desperately isolated.

“This is a clear sign that these climate denier’s extreme smear tactics have brutally backfired and that the momentum for a significant deal in Paris is moving full steam ahead. Even the fossil fuel companies that once lavished them with funding must be too embarrassed to be associated with this,” she said.

Heartland director of communications, Jim Lakely, said: “We applaud Indiegogo for adhering to such principles, though it doesn’t take much effort at all to better the Guardian and its leftist allies, who ceaselessly attempt to silence and crush all who oppose your radical agenda.”