China’s vast electric grids cause more fuss than any other country with renewable energy, but the system is also vulnerable to electricity shortages caused by adverse weather conditions. The need to ensure reliable power supply could encourage Chinese governments to use more coal-fired power plants.

China’s energy systems are rapidly becoming cleaner, setting new records for wind power and solar energy generation almost every month. The country’s overall greenhouse gas emissions – the highest emissions in the world are expected to peak soon and begin to decline. Wind, solar and hydroelectric power currently account for about half of China’s generation capacity, and is expected to increase to almost 90% by 2060, when the country promised to reach “carbon neutrality.”

This increasingly reliance on renewables means that the country’s electricity system is becoming increasingly vulnerable to changes in weather. Intermittent winds and sun can be replenished by more stable hydropower produced by huge hydroelectric dams enriched in southern China. But what happens when the wind and sun slump coincides with drought?

Jinjiang Shen Darian Institute of Technology in China and his colleagues modeled how power generation on increasingly renewable grids corresponds to these “extreme weather” years. They estimated how future mixing of wind, solar and hydropower behaves under the most favourable weather conditions seen in the past.

They found that future grids are much more sensitive to weather changes than they are today. In a very unfavourable year, 2060, it could reduce the amount of generation capacity by 12% compared to today’s grid, leading to a power shortage. In 2030, in the most extreme cases, they found that this leads to over 400 hours of blackout times, a power shortage of nearly 4% of total energy demand. “That’s not a number that everyone can ignore.” Li Shuo At the Institute of Policy Studies in Asia Association, Washington, DC.

In addition to the overall lack of force, drought could specifically limit the amount of hydroelectric power available to smooth out irregular winds and solar generation. This could also lead to a shortage of electricity. “It is essential to equip a suitable proportion of stable power sources that are less susceptible to weather factors to avoid large-scale, large-scale power shortages,” the researchers wrote in their paper.

One way to help is to run excess electricity more efficiently across states. By expanding the transmission infrastructure, researchers found that it could eliminate the risk of power shortages on today’s grids and reduce half of the risk by 2060. Adding new energy storage in tens of millions of kilowatts, whether using batteries or other methods, would also be alleviated against hydroelectric droughts.

According to Li Shuo, any additional storage amounts China needs to be added to achieve carbon neutrality “becomes an astronomical number.”

These changes are difficult, but they add that many storage is viable given the enormous amount of batteries already produced in China. Lauri Myllyvirta At the Finland Energy and Clean Air Research Centre. He says the country is also building 190 gigawatts of pumped hydropower storage. This says that it can provide long-term energy storage by using surplus electricity to pump water over the dam and releasing it when more electricity is needed.

But so far, the electricity shortage has primarily spurred the Chinese government to build more coal-fired power plants. For example, in 2021 and 2022, hydroelectric droughts and heat waves increased enough electricity demand to cause serious power outages; Continuous expansion of coal. Record hydropower generation in 2023 resulted in record time for emissions.

Chinese President Xi Jinping said coal would peak this year, but he has entrenched political support for power sources. “If China is struggling with another round of these episodes, more coal-fired power plants shouldn’t be the answer,” says Li Shuo. “It’s difficult to abolish coal. China loves coal.”