Chinese coal mining firm, Lu'an Group, said it has built the world's largest facility to generate power from methane gas emitted during coal mining, as the country looks to reduce poisonous gas emissions that contribute largely to pollution.

The official Xinhua news agency reported that Lu'an Group built the facility, which is capable of utilising 99% of methane gas discharged from the Gaohe Coal Mine in north China's Shanxi Province. The company would soon start operating the generator with a capacity of 30 megawatts.

The new technology will turn methane concentrations lower than 10%, which qualifies 81% of the gas released during mining, into electricity. The poisonous gas with concentrations of more than 10% is transformed into methyl alcohol and as fuel for internal combustion engines.

Jia Jian, deputy head of the Methane Gas Research Institute of the company, said the new technology has helped tackle the problem of how to dispose of the waste, Xinhua reported.

The newly built facility would decompose the gas into carbon dioxide and water under temperatures more than 950 Celsius, and use the heat and steam for power generation.

Jian added the project can help reduce 1.4 million tonnes of greenhouse gases and produce 200 million kwh of electricity a year.

Low-concentration methane gas has been a major contributor to China's environment pollution. Coal mines are estimated to produce more than 10 billion cubic metres of the gas every year, which leads to greenhouse gas emissions equivalent to 200 million tonnes of carbon dioxide.

The facility installed at Gaohe Coal Mine has drawn interest from a number of coal mining firms, as the coal industry is facing significant pressure from the central government to control carbon emissions, Xinhua noted.

China is targeting the reduction of carbon emissions per unit of gross domestic product by 40-45% from the level in 2005.