Gujarat – which mines coking coal in the Illawarra region from two longwall mines – would have been the worst hit producer under the carbon tax using 2011 data.

An estimated 760 kilotonnes of CO2, creating a liability of $17.5 million, would have taken 9.4% of the company’s total revenue for 2011 of $187 million.

Whitehaven would have paid 1.59% and Yancoal would pay 1.5% of their 2011 revenues.

“The impact may not appear material for the majority of ASX-listed companies but for companies operating in a high cost environment the loss of revenue will not be welcome,” Patersons said.

“The carbon tax will also increase the regulatory burden. Some of these companies are already dealing with falling commodity prices, the Mineral Resource Rent Tax and the unquantified indirect costs of the carbon tax such as electricity and the implementation and policing of the policy.”

Australia’s carbon pricing mechanism works by setting a fixed price for carbon units for three years (in real terms): 2012/13 $23 (Year 1), 2013/14 $24.15 (Year 2) 2014/15 $25.40 (Year 3).

From 1 July 2015, the carbon price will be flexible, and set by the market with reference to the demand for and supply of carbon units.

Most carbon units will be in auctioned by the clean energy regulator.

NSW’s coal mining regions will bear the brunt of the carbon tax, with the state Treasury predicting that by 2020 approximately 18,500 new jobs will be sacrificed in the Hunter region alone with another 7000 jobs foregone in the Illawarra.

Overall, the carbon tax will cost the mining industry $25 billion to 2020, including an $18 billion hit to the coal industry.

Coal is NSW’s biggest export commodity and the impact will be felt across the state’s economy, according to the NSW Minerals Council.