Recently, the Institute of Engineering Thermophysics of the Chinese Academy of Sciences has made important progress in the research field of megawatt-level constant pressure compressed air energy storage technology. For the first time in the world, the research and development team has completed the experimental study on the dynamic characteristics of megawatt-level constant pressure compressed air energy storage system under full working conditions. The centripetal expander developed by the research and development team has achieved 1.39 megawatts of power output and the isentropic efficiency of the whole machine reaches 88.28. The relevant results were published in the authoritative international journal “Journal of Energy Storage” (2026, 147: 120349).
The development of offshore wind power and other marine renewable energy is an important way to achieve the goal of “double carbon” in China. By the end of 2025, the global offshore wind power cumulative installed capacity of about 89.2GW, China’s 52 GW cumulative installed capacity ranked first in the world. Renewable energy such as scenery has intermittent, random and other characteristics, offshore wind power is anti-peak characteristics, lack of active support of conventional power supply, there is an urgent need for new energy storage technology to support the stable operation and reliable transmission of renewable energy power generation. Underwater constant pressure compressed air energy storage uses constant hydrostatic pressure to achieve constant pressure storage and release energy, without the need for bottom gas, and the energy efficiency can reach up to 80%. It is an effective way to solve the large-scale consumption of coastal renewable energy. However, the lack of research on the dynamic characteristics of this technology is the core bottleneck of large-scale engineering application.
in view of this technical bottleneck, the research and development team has developed the first megawatt-level constant pressure compressed air energy storage experimental platform in China, which can simulate the 700-meter water depth environment and support the experimental research of key components and complete machine system of constant pressure compressed air energy storage. This study reveals the dynamic regulation characteristics of power and speed in the whole process of system start-up, steady-state operation and shutdown, accurately depicts the temperature/pressure changes at all levels of the expander inlet and outlet, the pressure loss of the heat exchanger and the temperature/pressure changes in the constant pressure storage tank, and fills the blank in the study of the dynamic characteristics of the megawatt constant pressure compressed air energy storage system under full working conditions.
This study provides an empirical basis for the megawatt-level constant pressure compressed air energy storage system, and the proposed control strategy and component-level performance indicators provide an important reference for the engineering design, optimization and large-scale application of the technology. The rapid adjustment capability verified by the experimental system can effectively support the flexible peak demand of the power grid, which is of great significance to promote the large-scale grid-connected consumption of coastal renewable energy such as offshore wind power and the construction of a new coastal power system.
The research is supported by the National Natural Science Foundation of China, the Youth Talent Project of the China Association for Science and Technology, the National Key Research and Development Program, and the Key Laboratory of Long-term Scale Energy Storage.
