The Jinyun hydropower project is a 1.8GW pumped storage power plant under construction in the Zhejiang province of China.

Zhejiang Jinyun Pumped Storage, a joint venture of State Grid Xinyuan (70%) and State Grid Zhejiang Electric Power (30%), is developing the project with an estimated investment of £1.14bn ($1.5bn).

The Zhejiang Provincial Development and Reform Commission approved the project in June 2017.

Construction works were started in August 2020, while the first pump turbine unit is expected to commence operations in 2025. The remaining five units are expected to come online by the end of 2026.

At full capacity, the Jinyun pumped storage power plant is estimated to consume up to 2.4 terawatt-hours (TWh) of surplus electricity a year from the grid while operating in pumping mode during low electricity demand and generate up to 1.8TWh of electricity a year by releasing the stored water from the upper reservoir during peak electricity demand.

Jinyun hydropower project location and site details

The Jinyun pumped storage hydroelectric power project is located in Dayang and Fangxi, in Jinyun county, Lishui city, Zhejiang province, China.

The project site lies in the middle-low mountainous area of southern Zhejiang, on the south-west side of the Kuocang Mountains.

The upper reservoir will be located in the Caotou village in Dayang town, while the lower reservoir will be located on the Fangxi River, approximately 1.9km upstream of the Fangxi Township.

Reservoir and dam details

The lower reservoir of the project will be created with the construction of a 92.6m-high reinforced concrete dam with a crest width of 10m. The lower reservoir will have an active storage capacity of 15.3 million cubic meters (Mcm).

The upper reservoir will be created with the construction of a 59.2m-high reinforced concrete dam 59.2m with a crest length of 214m. It will have a water storage capacity of 12.62Mcm.

Jinyun pumped storage power plant make-up

The Jinyun pumped storage hydroelectric power station will comprise an underground powerhouse equipped with six vertical-axis Francis reversible pump turbine units of 300MW capacity each. The turbines will operate at a net water head of 589m.

Power evacuation

The electricity generated by the Jinyun pumped storage power station will be evacuated into the grid through two 35km-long 500kV power transmission lines.

Contractors involved

The 14th Bureau of Hydropower Construction was contracted to construct upper and lower reservoirs, water delivery system, powerhouse, and switch station of the Jinyun pumped storage project.

Harbin Electric (HEC) will manufacture and supply six reversible pump turbines and generators for the project.

China Northwest Research Institute was contracted in November 2017 to provide construction supervision services, while the East China Institute of Technology was engaged to perform surveys, water storage level selection, and site layout planning for the project.