New coal mining capacity fell to a 10-year low in 2024, but future projects especially in major producer China still risk oversupply, said a new report from US think tank Global Energy Monitor on Tuesday.

New mines opened globally in 2024 can dig up about 105-million tons of coal per year, down 46% from 2023 and the smallest increase in a decade, the report found. That is about 1% of the 8.9-billion tons of global capacity in 2024.

Construction plans in top producers China and India slowed in 2024 from previous years, explaining why new capacity fell to a 10-year low, the report said. But the researchers said the slowdown might not continue.

"The slowdown likely reflects delays in expansion approvals, the inherently lengthy nature of coal mine development phases, and a potential easing of supply-demand pressure following the pandemic-fuelled surge in capacity additions over the previous two years."

In China, coal mine approvals surged in 2022 after a coal and power shortage raised energy security concerns, but then dipped again as shortages turned to oversupply.

Despite the drop in 2024, the world is still planning new mines that could produce over 2 billion tons per year of coal.

Of the 2.27 billion tons per year in capacity under development, 1.35 million tons are in China, more than the rest of the world combined. If these projects move forward, China could see another round of overcapacity similar to 2012-2025, the researchers said.

In 2015, China had to undertake major supply side reforms to shutter excess steel and coal capacity - a period that has come into the spotlight as China's industrial sector again struggles with crushing oversupply.

The GEM data spans 850 new mines, expansions and recommission projects, and China, India, Australia, and Russia make up almost 90% of the proposed developments.

The 2024 slowdown in new capacity isn't enough to meet global climate targets, which call for significantly cutting instead of adding coal production, the researchers said.

Limiting global warming to 1.5 degrees would require reducing coal production 75% by 2030 from 2020 levels, according to a UN estimate.

One of China's proposed mines, the Changtan surface coal mine in Inner Mongolia, would be one of the world's top mines for emissions of methane, a particularly potent greenhouse gas, GEM said.