The Ninghai pumped-storage power project under construction in the Zhejiang province of China will comprise four generating units for a total capacity of 1.4GW.
State Grid Xinyuan Company, a subsidiary of the State Grid Corporation of China (SGCC) is developing the hydroelectric facility with an estimated investment of approximately £915m ($1.16bn). The construction works on the project were officially started in December 2017.
While the pre-feasibility study of the Ninghai pumped-storage power station passed the acceptance review by China’s General Institute of Hydropower and Water Conservancy Planning and Design in September 2013, the Zhejiang Provincial Development and Reform Commission approved in project June 2016.
The first pump-turbine unit of the project is expected to come online by April 2024, with the entire facility planned for completion in 2025.
At full capacity, the pumped-storage power station is expected to generate up to 2.345 billion kilowatt-hours (kWh) of electricity a year.
Location and site details
The Ninghai pumped-storage power project is located in the Dajiahe Town of Ninghai County, near Ningbo, in the Zhejiang province of China.
The project site lies in the Chashan Forest Farm area, within the Yongtaiwen power load centre region.
Ninghai pumped-storage facility make-up
The Ninghai pumped-storage hydroelectric facility will comprise upper and lower reservoirs connected with a water delivery system, an underground powerhouse, and a surface switch station.
The underground powerhouse measuring 179m-long and 57m-high will be equipped with four 350MW reversible pump-turbine units along with generator motors.
The other components of the project include a 500kV switchyard, a wastewater treatment system, a traffic tunnel, auxiliary caverns, ventilation and safety tunnels, upper drainage corridors, access roads, branch tunnels, tailgate transportation tunnel, and the main transformer air inlet tunnel.
The project also involves the construction of the 160m-long Tankenggou Bridge as the main passage to approach the pumped-storage power station.
Reservoir and dam details
The upper reservoir of the Ninghai pumped-storage power station will have a maximum dam height of 63.6m. It will be located in the centre of the Chashan Forest Farm, in the upper reaches of the Wenxi.
The lower reservoir is a mountain canyon reservoir that lies on a tributary of the Shimen River near Zhangkeng village, in the Dajiahe town.
It features a concrete face rock-fill dam with a crest elevation of 148m along with a crest length of 280m and a crest width of 8m. The maximum height of the lower reservoir dam is approximately 96m.
The electricity generated by the Ninghai pumped-storage power station will be evacuated to the Zhejiang Power Grid through a 500kV power transmission line.
Toshiba Hydro Power Systems (THPC) won a contract from SGCC for the supply of four pumped-storage hydroelectric equipment along with the balance of plant (BOP) systems for the project in February 2021.
The 12th Bureau of Hydropower was awarded a contract for the civil construction and metal structure works in August 2019. It was also previously contracted by State Grid Xinyuan Company for the construction of caverns and roads in December 2017.
Hebei Equipment Company received the order to supply 10kV switchgear equipment for the Ninghai pumped-storage power station in January 2019.
Kunshan Kedifa Ventilation Equipment Company was subcontracted by the 12th Hydropower Bureau for the supply of Swedfan high-pressure axial fans.