On May 25, China’s first large-scale lithium-sodium hybrid energy storage station — the Baochi energy storage station developed by CSG — was officially put into operation in Wenshan Zhuang and Miao Autonomous Prefecture, Yunnan Province.
Based on two charge-discharge cycles per day, the station can regulate up to 580 million kWh of electricity annually — enough to meet the yearly power needs of approximately 270,000 households. Notably, green electricity accounts for 98% of this total.
The station features a domestically developed grid-forming sodium battery system that can intelligently detect grid fluctuations caused by new energy inputs and adjust voltage and frequency in real time. This enables it to effectively smooth out the variability of renewable energy sources and support their large-scale integration into the power grid, as well as their participation in electricity market transactions.
A researcher from the Energy Storage Research Institute of CSG Energy Storage Co., Ltd., noted that the integration of lithium and sodium battery technologies in a single system has expanded the application potential of sodium-ion energy storage in China. It also advances the development of the new energy storage industry and is expected to be widely applied in the country’s western regions with high levels of renewable energy generation, supporting the stable transmission of green electricity.
China Southern Power Grid (CSG) is a major state-owned enterprise administered under the SASAC, providing power supply services for Guangdong, Guangxi, Yunnan, Guizhou, and Hainan, as well as Hong Kong and Macao SARs.
CSG’s power grid covers the five provincial-level regions in southern China and is connected to the power grids of Hong Kong and Macao SARs, as well as Southeast Asian countries, with a power supply area of one million square kilometers, serving a population of 272 million.
With the grid spanning nearly 2,000 kilometers from east to west, CSG is connected to various power sources, including hydro, coal, nuclear, gas, wind, solar, biomass, pumped storage, and new energy storage.
With AC/DC hybrid, CSG specializes in long-distance and large-capacity UHV power transmission, which requires experienced operating skills and complex technologies to ensure safety and stability. With its core technologies of UHVDC and VSC-HVDC, safe and stable operation of large power grids, energy conservation and economical operation of the power grid, large-capacity storage, and application of superconductors, CSG has created and is running the world’s first ±800 kV UHVDC power transmission project and first ±800 kV UHV flexible DC project. The UHVDC project has won the Grand Prize of the National Science and Technology Advancement Award. These achievements have marked CSG’s world-leading position in the field of UHV transmission. CSG has established eight AC and eleven DC transmission lines for the west-to-east power transmission program, each operating at 500 kV or above, with a total power transmission capacity exceeding 58 GW.