GREENPEACE is seeking to cast a pall over an enormous coal mine, rail and port project worth billions and proposed for the Galilee Basin by commissioning a report through an American group often used by environmental activists.
A report from the Institute for Energy Economics and Financial Analysis is warning the $16.5 billion plan from Indian energy giant Adani is "uncommercial".
Co-author Tom Sazilla said Adani's Carmichael Coal project was "on the wrong side of the boom".
"It might have been viable five years ago but the market has moved on," he said.
"Adani bought in at the peak of the coal cycle but failed to predict the structural decline of coal."
In the past 12 months, the IEEFA has published three reports funded by Greenpeace and opposing coal investment or development.
In June, the group published a report titled Stranded, which questioned the profitability of Adani's rival GVK, also developing coal in the Galilee.
The strategy of "increasing investor risk" was outlined in a Greenpeace document for "Stopping the Australian Coal Export Boom" in 2011.
The publishing of the report comes one day after the Queensland Government released studies into Adani's Carmichael project to the public for discussion.
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