Recently, the first heat exchanger of Unit 2 of the Huaneng Jintan 2×350 MW Salt Cavern Compressed Air Energy Storage Power Generation Project, constructed by SEPCO1, was successfully hoisted into place, kicking off the installation of unit equipment and marking a new stage in the project's construction.

As key equipment of a non-supplementary-fired compressed air energy storage power station, the heat exchange efficiency of the heat exchanger directly affects the power generation efficiency of the unit. The heat exchanger area of Unit 2 of the project is mainly divided into the expansion-side heat exchanger area and the A/B train compressor interstage heat exchanger area, with a total of more than 40 core pieces of equipment such as hairpin-type and shell-and-tube heat exchangers designed for installation. The one hoisted into place this time is a shell-and-tube expansion-side four-stage gas-water heat exchanger, with a length of 21.4 meters and a weight of 152.5 tons. It is the longest and heaviest heat exchanger in this system, presenting great hoisting difficulty and requiring high positioning precision.

To ensure the smooth progress of equipment installation, the Huaneng Jintan Project Department of SEPCO1, based on the heat exchanger supply schedule, planned and deployed in advance and conducted simulation demonstrations. It carefully organized, scientifically arranged and standardized all work including the preparation and submission for approval of the hoisting plan, the layout of hoisting machinery, site and road coordination, and personnel and equipment allocation. Safety and technical briefings for personnel and verification of each stage were completed in advance. Overcoming challenges such as narrow working space and the large size and weight of the equipment, the project department finally completed the unloading, hoisting and positioning of the heat exchanger safely and smoothly under the full supervision of the owner and the supervision unit, laying a solid foundation for subsequent work.

As a new type of long-duration energy storage power station, the Huaneng Jintan 2×350 MW Salt Cavern Compressed Air Energy Storage Power Generation Project is expected to charge and discharge 330 times a year, storing energy for 8 hours and generating power for 4 hours. When the station is charging, the interstage heat exchangers on the compression side recover the large amount of high-quality compression heat generated during air compression. When the station is generating (discharging), the stored compression heat is used to heat the compressed air released from the salt cavern through the expansion-side heat exchangers, which then enters the air turbine generator to produce electricity. The whole process requires no fossil fuel supplementary firing, enabling efficient resource utilization and zero carbon emissions while avoiding environmental pollution.

It is reported that the project is currently the compressed air energy storage power station with the largest single-unit power, the largest total capacity and the highest comprehensive efficiency in the world. A single charge can store 2.8 million kWh of electricity, and the annual power generation will reach 924 million kWh, equivalent to saving 270,000 tons of standard coal and reducing carbon dioxide emissions by 520,000 tons. It can effectively enhance the grid's regulation capacity and the absorption capacity of new energy, promote the efficient use of renewable energy, contribute energy storage support to the early realization of China's "dual carbon" goals, and serve the national energy security strategy.