Large balancing areas and dispersed renewable investment enhance grid flexibility in a renewable-dominant power system in China

Renewable energy is poised to play a major role in achieving China's carbon neutrality goal by 2060; however, reliability and flexibility is a big concern of a renewable-dominant power system. Various strategies of enhancing flexibility are under discussion to ensure the reliability of such a system, but no detailed quantitative analysis has been reported yet in China. We combine the advantages of a capacity expansion model, SWITCH-China, with a production simulation model, PLEXOS, and analyze flexibility options under different scenarios of a renewable-dominant power system in China. We find that a larger balancing area offers direct flexibility benefits. Regional balancing could reduce the renewable curtailment rate by 5-7%, compared with a provincial balancing strategy. National balancing could further reduce the power cost by about 16%. However, retrofitting coal power plants for flexible operation would only improve the system flexibility marginally.

Automated summary

Renewable energy is expected to play a significant role in China's goal of carbon neutrality by 2060. However, ensuring reliability and flexibility in a renewable-dominant power system remains a challenge. This study combines capacity expansion and production simulation models to analyze flexibility options under different scenarios in China. The findings suggest that larger balancing areas offer direct flexibility benefits, and regional and national balancing strategies can significantly reduce renewable curtailment and power costs.