The Panlong pumped storage power project located in the Qijiang District, Chongqing, China comprises four generating units for a total capacity of 1.2GW.

State Grid Xinyuan Company, a subsidiary of the State Grid Corporation of China (SGCC), is building the hydroelectric facility with an estimated investment of £718m ($1.11bn).

China’s National Development and Reform Commission approved the project in June 2014, while the main construction works were started in September 2015.

Scheduled for completion by 2022, the Panlong pumped storage power station is intended to address peak power demands and provide stability to the Chongqing power grid.

The project will also help in offsetting up to 1.5 million tonnes (Mt) of CO2 emissions and up to 1Mt of coal consumption a year.

Location and site details

The Panlong pumped storage power station is located close to Sichuan Hydropower Base, at Zhongfeng, in southwest Qijiang, approximately 80km away from Chongqing City, in China.

Panlong pumped-storage facility make-up

The Panlong pumped storage hydroelectric facility comprises an underground powerhouse, upper and lower reservoirs connected through a water delivery system, and a ground switch station.

The powerhouse will be equipped with four 300MW single-stage, vertical shaft, mixed-flow, reversible pump-turbine units operating at a design water head of approximately 462m.

The water delivery system will comprise the water inlet and outlet structures and the main water diversion system comprising two water diversion tunnels, and an upstream surge chamber.

Reservoir and dam details

The upper reservoir is located upstream of the Beaulieu River tributary grooves. It has a normal storage level of 995 and a dead storage level of 981m. While the total storage capacity of the reservoir is approximately 1.1 billion cubic metres, the regulating storage capacity is approximately 705 million cubic metres (mcm).

The upper reservoir consists of a main concrete dam and the Dahuangou auxiliary rockfill dam. While the main dam is 52m-high and 174m-long, the auxiliary dam is approximately 31m-tall and 89m-long.

The water delivery system starts from the northeast side of the mountain from the upper reservoir to Liujiayuan on the right bank of the lower reservoir.

The horizontal distance between the upper and the lower reservoir is approximately about 1.8km.

Power evacuation

The electricity generated by Panlong pumped-storage power station will be evacuated from the transformer tunnel to the Chongqing power grid through a 500kV transmission line.

Contractors engaged

The Eighth Hydropower Bureau of China was contracted by SGCC for the mechanical and electrical installation works of the project in August 2019.

Dongfang Electric Company was contracted for the supply of four turbine-generator units and auxiliary equipment in June 2018.

The First Bureau of Hydropower has been engaged in the construction of the main and auxiliary dams of the upper reservoir.

Energy China Gezhouba Group was contracted for the construction of the powerhouse along with the main transformer tunnels.

Fifth Hydropower Bureau was contracted to provide the engineering test and the technical inspection services for the Panlong pumped storage project.