This week, China's environment minister, Li Ganjie, said the country has reduced coal dependency by nearly 20% in the past year, however, the war on smog is getting harder.
"In reality the pressures are huge and it isn't easy to be optimistic about the trends," he said.
"The things that could easily be done have already mostly been done, and the things that need to be done afterwards are much harder."
Reporting on the Minister's statement, the World Economic Forum (WEF) noted that while China cut the share of coal in its total energy mix to 59% last year , down from 68.5% in 2012, it remained too high.
There were also still regional disparities in the way environmental protection was being enforced, Li added.
According to Li, China has installed ultra-low emissions technology at more than 80% of its total coal-fired power generation capacity.
The WEF noted that China's winter heating programme used to burn an estimated 400 million tonnes of coal a year, and switching it to cleaner types of fuel was identified as a major part of the country's war on pollution, now in its sixth year.
The programme to convert households to low-emission heating ran into difficulties last winter amid widespread natural gas shortages, but 4.8 million households still managed to make the switch from coal to natural gas and electricity last year, up from 4 million households switched in 2017, Li said.