On April 29, 2026, the Chongqing Guizhou Back to Back Interconnection Project (Guizhou side) started construction in Xishui, Zunyi. Southern Power Grid invested 580 million yuan and plans to put it into operation in June 2027. It will build 87.9 kilometers of transmission lines and 179 iron towers to strengthen the mutual power supply between Chongqing and Guizhou.

580 million yuan to open the double network aorta

This project is a key project to implement the new national energy security strategy, with the mission of opening up the interconnection channel between the State Grid and the Southern Power Grid. The Guizhou side is under the construction of Southern Power Grid, with an investment of 580 million yuan. The main construction content includes the expansion of three outgoing intervals from Hongcheng 500 kV substation, the construction of two new converter stations to Hongcheng 500 kV transmission lines, with a total length of 87.9 kilometers, and the construction of 179 new iron towers. The project is scheduled to be completed and put into operation in June 2027, which will significantly enhance the emergency dispatch capability of the Southwest power grid to cope with extreme weather conditions.

Complex geological construction in mountainous areas

The Guizhou side project is located in the mountainous area of northern Guizhou, with severe terrain undulations and strong karst development, facing enormous challenges in construction. There are a total of 352 cross crossing operations along the entire line, which require crossing 8 mineral deposits and 6 oil and gas pipelines. Fu Chengpeng, Deputy General Manager of the Construction Branch of Southern Power Grid Guizhou Power Grid Company, stated that the project department will strictly follow the principle of coordinated promotion of safety, quality, and progress, scientifically deploy construction forces, deepen cooperation and linkage with surrounding provinces such as Chongqing, and make every effort to create a safe, high-quality, green, and efficient inter grid interconnection project. Keywords: ultra-high voltage, electricity

Accelerate the delivery of clean energy

Since the 14th Five Year Plan, the demand for electricity in Chongqing and Guizhou has grown rapidly. It is expected that the maximum electricity load in Guizhou and Chongqing will increase by an average of 6.4% and 7.8% annually during the 15th Five Year Plan period, respectively. After the project is put into operation, it will further strengthen the interconnection between State Grid and Southern Power Grid, achieve optimized allocation of power resources in Chongqing and Guizhou, provide a solid channel for the wider consumption of clean energy such as hydropower, wind power, and photovoltaics in Guizhou, and provide strong power guarantee for the Chengdu Chongqing economic circle.Editor/Cheng Liting