State Grid Huai'an Power Supply Company escorts salt cavern energy storage project to be connected to the grid ahead of schedule

On May 25th, the 220 kV transmission line project of Huai’an Guoxin Salt Cave Compressed Air Energy Storage Project, constructed by State Grid Huai’an Power Supply Company, was officially put into operation.

This milestone event marks the full integration of Jiangsu Province’s first compressed air energy storage demonstration project utilizing salt cavern resources into the power grid, providing important support for the energy structure transformation in East China.

Mechanized Construction Scene of 220 kV Transmission Line Engineering for Huai’an Guoxin Salt Cave Compressed Air Energy Storage Project (Wang Jiahui)

The project is located in Shanyang Street, Huai’an District, Huai’an City. It relies on the abundant underground salt resources in the area and innovatively adopts the non supplementary combustion “high-temperature adiabatic compression” technology of molten salt+pressurized heat medium water storage. The design energy conversion efficiency of this technology is as high as 71%, far exceeding traditional compressed air energy storage. After the project is put into operation, it can save 250000 tons of standard coal and reduce 600000 tons of carbon dioxide emissions annually.

The 220 kV transmission line project supporting this project is a key link in the project’s grid connection. The transmission line starts from the Yanxue Energy Storage Power Station and ends at the 500 kV Shanghe Substation. A new double circuit overhead line of 16.9 kilometers will be built, crossing transportation arteries such as the Yanluo Expressway, involving the assembly of 57 towers and multiple secondary risk operations.

During the project construction period, State Grid Huai’an Power Supply Company, in conjunction with local governments, established a special team to simplify the approval process, efficiently complete the permit for crossing highways, and actively adopt mechanized tower assembly, intelligent tensioning equipment, and unmanned aerial vehicle acceptance methods to increase construction efficiency by 40% and reduce risk workers by 60%. In addition, the company has made detailed arrangements for construction organization and material supply, coordinated the 220 kV power outage window period, and determined the 220 kV power outage plan 8 months in advance. At the same time, experts have been dispatched to the factory to supervise the supply of tower materials, ensuring the smooth progress of the project.

The operation of this project will significantly enhance the regional power grid regulation capability. According to calculations, the project is expected to compress energy storage for 16 hours per day and generate electricity continuously for 8 hours. A single discharge can meet the daily electricity demand of about 300000 households, further enhancing the power grid’s ability to “peak shaving and valley filling” during peak summer periods. (Wang Xi, Wang Jiahui)