As a part of its efforts to move away from dependence on coal burning as an energy source, the Chinese government recently approved the construction of nine large-scale plants that will convert coal into synthetic natural gas. While these will alleviate the smog crisis caused by coal burning in urban areas, several studies raise concerns about the overall environmental impacts of this initiative, finding that the new synthetic natural gas plants may cause more problems than they solve.
Coal burning currently accounts for 68 percent of China’s energy production. While coal is plentiful in China, it is also a leading source of air pollution. Rather than reducing China’s dependence on coal as a primary energy source, the development of coal-fueled SNG plants merely distances the burning of coal from urban centers where its consequences are widespread and well publicized.
Converting coal to natural gas is significantly more energy-intensive than traditional methods of SNG production and generates increased levels of greenhouse gas emissions. A recent study published by the Duke University Center on Global Change finds that one coal-fueled SNG plant will emit up to 21 billion tons of carbon dioxide over a typical 40-year lifetime, seven times what a traditional SNG plant emits. Furthermore, if the SNG is used to generate electricity, the lifecycle emissions of carbon dioxide will be between 36 percent and 82 percent greater than if the electricity were generated from burning coal. Duke researcher Robert B. Jackson states that, “using coal to make natural gas may be good for China’s energy security, but its an environmental disaster in the making.”
Despite this, coal gasification plants appear poised to grow rapidly in China. “It’s been less profitable to go after natural gas than to make natural gas out of coal,” says Jackson. Indeed, on Oct. 6, the regional government of Xinjiang announced a $29.7 billion investment to begin construction of another coal gasification plant. This will be the largest plant to date, and the fourth to be approved in the Xinjiang province. Currently, nine government-operated plants have received approval and thirty privately owned ventures are awaiting approval to begin construction. If all of the plants become active, they would together be capable of producing more than 200 billion cubic meters of SNG per year—36 percent more than was consumed in all of China during 2012. The proposed plants are located almost entirely in rural regions of northwestern China and Inner Mongolia.
In addition to carbon dioxide, coal gasification plants emit hydrogen sulfide and mercury, pollutants known to adversely affect human health and that are much more water-intensive than other production methods. The effects of these externalities will be felt locally in the regions where the plants are located. Duke University researchers Jackson and Chi-Jen Yang point to potential environmental justice issues in the unequal distribution of environmental consequences and economic benefits. Developing coal-fueled SNG plants provides affordable and plentiful energy that can be easily piped to the urban centers of the east, while alleviating the air pollution felt by cities. However, this may come at the expense of the environmental and public health conditions in northwestern China and Inner Mongolia.
While China should be applauded for its efforts to diversify away from coal, the development of coal gasification SNG plants is not a viable replacement for coal burning. Distancing the pollutant emissions from urban centers at the expense of local environmental quality and global greenhouse gas levels may alleviate short-term pressures but does not constitute a sustainable energy strategy in the long-term.
Emma Marshall, Guest Writer