On Tuesday, the ministry released rules enabling provincial governments to set emission limits for the first time for big-power enterprises.

Companies can buy the right to pollute from those with a lower carbon footprint, but by making it more expensive to do so, the scheme is intended to bring down total emissions.

However, despite ambitious renewable energy goals, 60 percent of China's power is still supplied by coal, and experts warn the strong coal lobby will be lobbying hard for favorable carbon caps.

Under the new regulations, from February 1, more than 2,200 companies that produce more than 26,000 tons of greenhouse gases per year will begin trading their emission quotas.

The national system of China is expected to eclipse that of the European Union to become the largest carbon trading program in the world (ETS).

Prior to 2030, Beijing vowed to peak emissions and become carbon neutral 30 years later. But initial plans to curb pollution from seven other sectors, including aviation, steel and petrochemical processing, have been reversed.

In 2019, China's greenhouse gas emissions were measured at 13.92 billion tonnes, around 29 percent of the world's global warming-related total.

Once fully operational, according to the International Carbon Action Partnership, the ETS will cover around a third of China's national emissions.

Maritime Business World