China has restarted construction on more than 50 gigawatts of suspended coal-fired power plants last year, bucking a global shift away from fossil fuels, a new study shows.
China has repeatedly pledged to reduce its reliance on coal, a major source of smog and climate-warming greenhouse gases, and it has already cut coal's share of its total energy mix to 59 per cent, down from 68.5 per cent in 2012.
But satellite images show China "quietly resumed" construction in 2018 on dozens of previously shelved plants, making it a "glaring exception to the global decline", said a joint report by environmental groups Global Energy Monitor, Greenpeace and the Sierra Club.
The report warned that China could build an additional 290 GW of capacity - more than the whole of the United States' coal capacity - and still remain within the 1300-GW cap for national coal-fired power generation proposed by the China Electricity Council, an influential industry group.
Lauri Myllyvirta, analyst with Greenpeace's Global Air Pollution Unit, said Chinese firms are now "pushing for hundreds of additional coal-fired power plants".
"Another coal power construction spree would be near impossible to reconcile with emission reductions needed to avoid the worst impacts of global warming," he said.
Worldwide, the number of newly completed coal projects fell 20 per cent in 2018 and plant retirements continued at a record pace, the study said.
But China's relationship with the dirtiest of fossil fuels remains ambivalent.
The domestic coal power capacity under construction rose 12 per cent in 2018, though it was still a third lower than what was being built in 2015. Beijing has also cut back dramatically on new project permits.
While China has vowed to cap consumption nationally and even make cuts in regions like Beijing, Hebei and Henan, overall coal-fired generation has increased, particularly from new "coal bases" in the nation's northwest.
And though it has promoted alternative fuels at home and built hundreds of solar and wind farms, China is still financing more than a quarter of the new coal-fired plants abroad.
China is also keen to prop up coal prices and ensure a "soft landing" for a commodity responsible for millions of domestic jobs in struggling industrial districts.
The availability of increasingly competitive and reliable renewable energy, however, has led to concerns that coal investments will soon become unprofitable "stranded assets".
The State Development and Investment Corporation, a central government-run investment group with significant holdings in the power sector, announced earlier this year that it would no longer fund coal projects.
Australian Associated Press