It’s raining again in China. Reservoirs are filling, and the country’s massive hydropower complex is generating power at closer to normal capacity after years of drought. This could mean that China’s emissions of greenhouse gases — the largest in the world — may be peaking, or even already have peaked. And as goes China’s emissions, so go the world’s.
Hydro generation has grown 16% through May of this year compared to January through May of last year, according to a Reuters analysis of Chinese government statistics. “Hydro storage is about as good as it’s ever been” in China, Alex Turnbull, an investor and energy researcher based in Singapore, told me.
China produces almost 30% of the world’s hydropower, but output in the country has fallen in recent years due to declines in rainfall. China produced some 1,226 terawatt hours of hydro power in 2023, according to the 2024 Statistical Review of World Energy, down about 5% from 1,298 in 2022 and down substantially from the recent maximum output of 1,322 in 2020. From 2013 to 2023, Chinese hydro output grew by about a third, a 3 percent annual growth rate, during that same period, wind output has grown by over 500%. Solar output, meanwhile, increased by nearly a factor of 70.
Even in spite of this phenomenal growth in wind and solar capacity, hydropower is still China’s largest source of clean energy, according to the clean energy think tank Ember, responsible for 13% of its electricity generation. Almost two-third comes from fossil fuels, largely coal.
The country’s 2022 drought wreaked havoc on China’s economy, with factories going idle for want of power and cities shutting off lights in order to conserve. Globally, hydropower output hit a five-year low in 2023, according to Ember, largely on the back of China’s slump. This meant increased global coal usage, driving up overall power sector emissions by 1% and preventing what would have otherwise been a fall in global power emissions.
“The expectation with more hydro coming back on line is much less coal generation,” Jeremy Wallace, a professor of China studies at Johns Hopkins School of Advanced International Studies and Heatmap contributor, told me.
The water level in the Yangtze River has risen in the past few weeks due to heavy rainfall, Reuters reported, which is not an unalloyed good — it could also mean more flooding and landslides throughout the summer, government meteorologists projected. Floods in the Yangtze and its tributaries are recurring and tremendous risks in China. Floods in 2011 caused by heavy rain following a drought killing around 200 people and displaced hundreds of thousands.
China accounts for about 26% of global emissions, so if its emissions have indeed peaked, that would be very good news for the rest of the world. “China’s economy is growing and it’s using more electricity,” Wallace told me, “but almost all of that electricity growth has been from clean sources.”
China’s carbon dioxide emissions fell slightly in March of this year after rising steadily following the end of its zero-Covid policy in 2022, according to an analysis for CarbonBrief by Lauri Myllyvirta, a senior fellow at Asia Society Policy Institute and lead analyst at the Centre for Research on Energy and Clean Air. That is due in part to the government’s investments in non-emitting energy — 423 terawatt hours per year installed in 2023 alone, “equal to the total electricity consumption of France,” per Myllyvirta’s analysis — and in other part to a transformation in its industrial balance.
Over the past few years, China’s economic engine has shifted from urban construction, dependent on emissions-heavy steel and cement, towards relatively less carbon-intensive manufacturing, Wallace said.
Turnbull shared a similar take. “All the sectors which comprised all the ferocious power demand growth” are “going down” or are “flat to down-ish,” he said, referring to industrial sectors like steel. Meanwhile, “the demand side doesn’t look like it’s growing anywhere near like it is before.”
“I think this is it,” Turnbull said. “This is the peak.”
