애써 늘린 재생에너지 버려져…‘전력망 문제’ 중국서 해법 찾는다

As China ramps up renewable energy production, it faces the challenge of "power grid problems." Energy grids require a balance between production and consumption, and a growing share of intermittent renewable sources like wind and solar can disrupt this balance. To mitigate this, grid managers implement "output controls" or curtailment, reducing or shutting down the output of certain power sources.

In South Korea, regions with high renewable energy capacity, such as the southern part, are experiencing frequent output controls, which some consider a major obstacle to achieving the 2030 goal of 100 gigawatts of renewable energy. The green transition research institute analyzed China's case, showing how the country managed to increase renewable energy while reducing output controls.

China had a rapid expansion of wind and solar capacity from the mid-2010s, with annual increases of 20% and 46%, respectively. However, output controls also increased, reaching 12.6% for solar and 17.1% for wind between 2015 and 2016. However, the extreme levels varied by location. The issue stemmed from a mismatch between power production and consumption, with most wind and solar installations in inland areas and high demand for heating and other consumption in coastal areas.

Additionally, power generation practices were heavily reliant on coal, with thermal power plants required to run at certain levels to ensure profits. The Chinese government set a target to lower output control rates to below 5%, implementing various policies, such as subsidizing coal power plants to reduce output, designating minimum guaranteed hours for renewable energy purchases, and encouraging local power demand creation.

Output control rates have since dropped significantly, reaching 4% for wind and 2% for solar between 2016 and 2019. However, there is a risk of output control rates rising again, as China continues to expand renewable energy capacity. The report suggests that China's experience demonstrates that it is possible to increase renewable energy while reducing output controls.

For South Korea, with its goal of 100GW of renewable energy by 2030, the report suggests exploring measures such as economic incentives for fossil fuel plants, boosting demand for power in renewable-rich areas, and redistributing losses from output controls. However, the recent Chinese experience with high output controls and increased coal power generation indicates that transitioning away from fossil fuels is not easy.

While the central government's policies play a role, local governments and market forces can also influence the situation.