BEIJING- China's planned coal-fired power capacity last year increased for the first time since Beijing imposed restrictions on new coal plant proposals and permits in 2016, a joint study by four international environmental groups shows.

The country, the world's biggest coal consumer, recorded 106.2 gigawatts (GW) of coal-fired power capacity in pre-construction development last year, a surge of 46% from 2018, the report said, indicating the country plans to add more coal plants in the next Five-Year-Plan period (2021-2025).

The increase comes after a large amount of coal power capacity reached advanced stages of construction in 2018, according to the report released on Thursday by Global Energy Monitor (GEM), Greenpeace International, the Sierra Club, and the Centre for Research on Energy and Clean Air.

Between 2016-2019, a total of 83.6 GW coal-fired power capacity under construction was suspended, the report said, but 85% of that has since been revived, mostly in 2018.

Newly installed coal-fired power capacity reached 43.8 GW in 2019, accounting for nearly two-thirds of the new coal fleet globally.

With the capacity of retired coal power plants reaching 7 GW last year, China's coal-fired power capacity increased by a net 36.8 GW, the report showed, much higher than an estimate from the China Electricity Council of 28.9 GW.

"As policymakers look for ways to stimulate the economy after the coronavirus crisis, a wave of new coal plants would be the worst kind of waste," said Lauri Myllyvirta, lead analyst at the Centre for Research on Energy and Clean Air.

But the report also said the increase of China's coal fleet would not necessarily lead to an increase in coal power use and greenhouse gas emissions.

The Chinese government last year relegated 40% of the 43.8 GW of newly commissioned coal power to emergency back-up status in order to restrict its usage.

It also issued investment warnings to 10 out of 33 regions, divided by grid systems, in mainland China in February, suggesting the economic returns from new coal-fired power plants in these regions could be lower than mid- to long-term government bond yields.

As Beijing's pushes to boost renewable energy consumption, the average running hours at coal plants in China were around 50%, the report said, adding to financial pressure on thermal power companies.

In December, China said it would slash around 25% to 33% of its total coal-fired power capacity by the end of 2021.

(Reporting by Muyu Xu and David Stanway; Editing by Kirsten Donovan) ((muyu.xu@thomsonreuters.com; +86 10 56692117;))