China looks set to hit peak greenhouse gas emissions five years earlier than expected, meaning that the country's emissions might start to decline within a decade. The nation's increased commitment to renewables could help keep the world within the warming limit that is widely believed to be necessary to prevent serious damage from climate change.

“This finding suggests it is increasingly likely that the world will avoid global warming of more than 2°C above pre-industrial levels,” claim the authors of the study, conducted by the London School of Economics. If their findings are correct, then China will peak at between 12.5 and 14 billion tonnes of carbon dioxide produced in 2025, after which emissions should hopefully start to decline.

Currently the largest consumer of coal in the world, China burns more of the stuff than the next four largest users combined. Despite also being the biggest investor in renewables, coal still provides the country with two-thirds of its energy. And as coal is the dirtiest fuel, emitting more CO 2 when burned than any of the others we use, this puts China at the top of the table for total greenhouse gas emissions. Interestingly though, if you look at the data per person, the U.S. and Russia take the lead.

Coal mine near Hailar, Inner Mongolia, China. Credit: Herry Lawford/flickr (CC BY 2.0)

Despite the huge environmental cost of burning coal, from the massive levels of pollution the country suffers from—killing an estimated half a million people each year—to the water shortages caused by the power plants, it’s often still the fuel of choice by China's industry. This is because it is cheap, easily extracted and can be sourced locally. But China may be heading towards change, as last year saw their first drop in coal demand in over a decade.

“Analysing trends in the key emitting sectors, we conclude that China’s greenhouse gas emissions are unlikely to peak as late as 2030—the upper limit set by President Xi Jinping in November 2014—and are much more likely to peak by 2025. They could peak even earlier than that,” the scientists write.

The authors also suggest that the previous commitment by the country’s president should be seen as a conservative estimate, as China “prefers to under-promise and over-deliver.” The earlier pledge was to use their “best efforts” to curb emissions by 2030 and, according to the authors, what we’re seeing now is the country’s best efforts working.

Many of these efforts are in response to the crippling problem of air pollution that is plaguing many of China’s largest cities. As well as being bad for the health of their citizens, China is also concerned that it is tainting the country’s image. This has helped drive the country's massive investment in solar, wind and hydropower. China now produces more renewable energy than all the power plants in Indonesia combined.

“The United Nations Climate Change Conference in Paris later this year will be more successful if governments everywhere understand the extent of change in China, its implications for global emissions, and the positive impact that China’s clean industrial development, investment and innovation plans are likely to have on global markets for clean goods and services,” say the authors.