China drought cuts hydropower output

In major news for China’s electricity system and emissions – and for the world, on 17 July, China’s National Bureau of Statistics  announced that despite overall electricity generation growing 3.8% year-on-year, hydropower output fell by nearly 23%  in the first half of 2023 – the largest drop among all electricity sources.

Hydro is China’s largest source of renewable power, accounting for 15% of electricity in 2022. The scale of the drop is so large that it was matched the growth of other renewable resources – wind and solar grew 16% and 7%, respectively – forcing an increased reliance on coal. Thermal power generation – largely coal – grew 7.5% in the first half of 2023, according to official data..

This year’s events come after two years of extreme summer droughts in 2021 and 2022. Southwest China is particularly reliant on hydro generation. In Sichuan and Yunnan provinces, for example, hydro meets around 80% of annual electricity demand, according the China Society for Hydropower Engineering.

In these provinces, 2023 was “20% drier” than 2022, Some provinces have of necessity moved to increase coal capacity. Of course, China is hardly alone in turning to coal during periods of drought, when hydro-power output is reduced. Switching from hydropower to fossil fuels during periods of drought has cost Western US states about $20 billion over the past two decades, according to new findings from Stanford University scientists. See

China’s “Action Plan for Carbon Dioxide Peaking Before 2030” emphasised that “we must insist [on] construction before destruction, stabilise energy stock and expand energy increment”, implying the country would continue to incorporate coal in its energy mix while the transition to clean energy develops.

This principle (先立后破) – sometimes translated as “build before breaking” – has been used in official pronouncements since 2021 and is taken to mean that new, low-carbon energy sources should expand before the use of coal starts to contract. The principle was mentioned again by president Xi Jinping in a national speech last week, delivered as US climate envoy John Kerry was leaving Beijing.

Notwithstanding recent shortages, China has the world’s largest undeveloped hydro-power potential.

SourceCarbon Brief <>, China Briefing email newsletter, 27 July 2023.