The world's second-largest economy is the biggest emitter of the greenhouse gases that drive climate change but is also a renewable energy powerhouse. It plans to reach net zero by 2060.

Coal has been a pivotal energy source in China for decades but explosive growth in wind and solar installations in recent years has raised hopes that the country can wean itself off the dirty fossil fuel.

However, according to a report from the Finland-based Centre for Research on Energy and Clean Air (CREA) and Global Energy Monitor (GEM) in the United States, China began construction on 94.5 gigawatts of coal power projects in 2024 -- 93 percent of the global total.

Although China also added a record 356 gigawatts of wind and solar capacity -- 4.5 times the European Union's additions -- the uptick in coal power risks solidifying its role in its energy mix, the report said.

"China's rapid expansion of renewable energy has the potential to reshape its power system, but this opportunity is being undermined by the simultaneous large-scale expansion of coal power," said Qi Qin, lead author of the report and China analyst at CREA.

The rise comes despite a pledge by Chinese President Xi Jinping in 2021 to "strictly control" coal power projects and increases in coal consumption before "phasing it down" between 2026 and 2030.

Coal production has risen steadily in recent years, from 3.9 billion tons in 2020 to 4.8 billion tons in 2024.

"Without urgent policy shifts, China risks reinforcing a pattern of energy addition rather than transition, limiting the full potential of its clean energy boom," the report said.

- Coal prioritised -

New permits for coal power projects fell 83 percent in the first half of 2024, prompting optimism that China's clean energy transition was gathering pace.

In November, a survey of experts by CREA and the Australian think tank International Society for Energy Transition Studies (ISETS) found 52 percent thought China's coal consumption would peak in 2025.

But coal power remained high in the latter months of 2024 despite China adding enough power from clean energy sources to cover its growth in electricity demand.

That suggested coal power was being prioritised over renewable sources in some regions, the report said.

"Chinese coal power and mining companies are sponsoring and building new coal plants beyond what is needed," said Christine Shearer, research analyst at GEM.

"The continued pursuit of coal is crowding out the country's use of lower-cost clean energy."

Analyst David Fishman agreed with much of the report but said he was "more optimistic" that coal would be phased out in the coming years.

The surge in coal power late last year may be "a short-term symptom of a market transitioning to true economic offtake... and not a sign of a system designed to benefit coal generators", Fishman, senior manager at the Lantau Group, told AFP.

- New targets -

China is due to announce details of its 15th Five-Year Plan -- for 2026 to 2030 -- in the coming months, likely including updated emissions and energy goals.

This month it was also due to submit new emissions targets, known as Nationally Determined Contributions (NDCs), under the 2015 Paris Agreement.

Only a handful of countries have submitted new NDCs so far.

China should "establish a total cap on coal-fired power generation" and formulate "a clear timetable for phasing out coal power", Gao Yuhe, Beijing-based project lead at Greenpeace East Asia, told AFP.

"The 2030 target for installed renewable energy capacity should be raised to expedite the replacement of coal power with renewable energy, aiming to achieve peak carbon emissions in the power sector before 2025," she said.