Heavy rains in China throughout May enabled the country to utilise more of the capacity at its cascade dams, increasing hydropower generation and reducing the need for coal-fired power production.

According to Reuters, hydroelectricity generation increased to 115 billion kilowatt-hours in May 2024, up 40% from the same month last year, when a prolonged drought caused a fall in river levels. Hydropower generation this May was the second highest for spring in the last ten years, not far from the record of 122 billion kilowatt-hours in the spring of 2022.  

China has struggled with temperamental hydro output in recent years. Between winter 2022 and spring 2023, most of south-west China, where much of its hydro infrastructure is located, experienced significantly less precipitation and higher temperatures than in previous years, leading to a sharp reduction in generation.

However, since the start of April this year, the country has experienced heavy rainfall, which is set to continue through July and August.

As such, hydro is acquiring an increasingly important role in China’s power generation mix. According to Power Technology’s parent company, GlobalData, of the total hydro capacity in the world, 29.56% is in China.

In addition, there are currently five large hydro power projects in development in the country, including the 60GW Medog Project set to enter commercial operation in 2033.

At the same time as the increase in hydro generation, China also generated record amounts of electricity from wind and solar, according to Reuters.

The increase in renewable energy generation has reduced the country’s reliance on thermal power from coal. Thermal power generation declined to 454 billion kilowatt-hours in May 2024, down from seasonal record of 471 billion kilowatt-hours in May 2023.

However, coal-fired power is still vital in China, making up nearly 60% of China’s electricity supply in 2023, according to government-backed industrial association the China Electricity Council.

According to a GlobalData report: “Due to the polluting nature of coal-based generation, China’s cities, which are powered by a huge array of coal-fired power plants, are earning a reputation as the most polluted cities in the world.

“Domestic coal production is also decreasing while demand for power is increasing. A large demand–supply shortfall may occur if the country is unable to continue importing coal from Indonesia. Being dependent on external coal supplies may endanger energy security,” the report said.

Speaking to Power Technology’s sister publication, Mining Technology, Christopher de Vere Walker, head of power utilities research at non-profit Carbon Tracker, said: “China’s market is driven by energy sovereignty” and in a world of geopolitical instability, “they will continue to put sovereignty over anything else”.

He added that, owing to this factor, the transition away from coal could take longer than expected, despite the build-out of renewables such as hydro.