The Greens have unveiled a plan to end all coal mining in New South Wales.

The environmental conservation party would ban new coal developments and put existing ones on a timeline toward closure.

They also want to adjust mining royalty levels to tax coal companies an extra $250 million a year, which would create a fund for a transition to more sustainable industries.

The Greens’ election policy for the March state poll was outlined just days after days after Premier Mike Baird faced noisy protests at the opening of the Whitehaven Coal mine at Maules Creek.

Greens upper house MP Jeremy Buckingham said many voters were angry and the Baird Government’s “rabid backing of coal”.

The Greens are using a recent article in the journal Nature as a justification for the end of NSW coal mining.

The report found that 95 per cent of Australian coal reserves would need to stay in the ground to meet global warming targets, which would allow just three more years of production in NSW at current rates.

“The question is will NSW have a planned and managed phase-out strategy for coal, or will we wait for a chaotic collapse of the industry?” Mr Buckingham asked.

“It will be a complex, long-term and difficult process, but we need to begin it now otherwise we will end up with a nasty shock.

“At the moment we have Mike Baird and the Coalition going hard on approving coal mines, and Labor in hiding on it. Labor are putting political pragmatism, and trying to win Hunter seats, ahead of what needs to be done,” he said.