Photograph by Liu Chan/Xinhua Press via Corbis Workers dismantling a facility in Chongqing, China, after a trial operation by a branch of Sinopec Recently China dramatically revised downward its ambitions for producing shale gas—slashing in half a target of producing more than 60 billion cubic meters annually by 2020, to just 30 billion cm. Meanwhile, the world’s largest emitter of carbon dioxide still aims to radically increase its output of synthetic gas derived from coal—from almost nothing today to 12 percent of gas consumption by 2020. Sinopec (386:HK) alone has just announced a $10 billion investment in coal-to-gas technology. The logic of the plan, in part, is to remove direct sources of air pollution from China’s smoggy city centers. Instead of burning coal for power and heating in urban areas, coal will be converted to gas at large power bases located in sparsely populated regions of western and northern China. So far, the central government has approved locations for at least nine large synthetic natural gas (SNG) plants; permit applications for about 30 additional plants are pending. However, simply locating these new plants outside of population centers does not mean that the conversion process is itself clean. According to a study (PDF) published last year in the journal Nature Climate Change, the process of mining coal and converting it into synthetic gas produces greater total greenhouse gas emissions—ranging from 36 percent to 82 percent in additional total carbon emissions, depending on whether the gas is ultimately used for powering vehicles or for generating electricity. “China has recently pushed for investments in large-scale coal-fuel-led synthetic natural gas plants. The associated carbon emissions, water needs and wider environmental impacts are, however, mostly neglected and could lock the country into an unsustainable development path,” the authors, both scientists at Duke University’s Center on Global Change, concluded. At least some experts in China’s government seem to be sounding notes of caution. In mid-July, China’s National Energy Administration published a report on its website urging stricter oversight of coal-to-gas projects and warning against the perils of “disregarding the environment and water resources.”source