According to CCTV Finance, compressed air energy storage technology has gradually matured over the past decade, and projects have begun to be implemented more rapidly in China since last year.
According to statistics, there are currently nearly 10 compressed air energy storage power stations in operation nationwide, with an installed capacity exceeding 200 megawatts. With the construction speed of compressed air energy storage projects accelerating significantly this year, the scale of projects under construction is several times that of completed projects.
New type of energy storage – compressed air energy storage
Compressed air energy storage refers to the use of electricity generated during periods of high volatility, such as wind and solar power, or periods of low grid load, to compress air into high-pressure air and store it in a sealed container. During periods of high grid load, the high-pressure air is released to drive a steam turbine to generate electricity.
Compressed air energy storage is currently mainly used for peak shaving and valley filling of the power grid, consumption of renewable energy on the power supply side, frequency and phase regulation on the power grid side, and on the user side, it is mainly used for some industrial parks for combined cooling, heating and power supply.
The entire compressed air energy storage system can be roughly divided into four parts: compressor, air storage tank, heat exchanger, and expander.
Compressed air energy storage classification
Compressed air energy storage has a very long history of development. The concept was first proposed in 1949. After years of research at home and abroad, there are now many forms of compressed air energy storage. According to the heat source and storage medium, it can be divided into non-insulated compressed air energy storage, adiabatic compressed air energy storage, isothermal compressed air energy storage and liquid compressed air energy storage.
Among them, non-insulated compressed air energy storage, which was the most widely used in early commercial applications, consists of a cavernous air storage chamber and a combustion chamber. When there is a power surplus, air is compressed into the cavernous air storage chamber; when there is a power shortage, high-pressure air is connected to the combustion chamber to burn fuel, driving an expander to generate electricity.
The difference between adiabatic compressed air energy storage and compressed air energy storage is that the compressed air is in a high temperature and high pressure state. When released, it can directly drive an expander to generate electricity without the need for combustion with chemical fuels, achieving zero emissions. The disadvantage is that the air compression process has high energy consumption and high requirements for equipment.
Isothermal compressed air energy storage uses methods such as pistons and spraying to make the air compression and expansion process close to an isothermal process through a liquid with a high specific heat capacity, thereby minimizing heat loss and improving system efficiency.
Liquid compressed air energy storage utilizes cooling and liquefaction technology to keep air in a liquid state. Upon release, it is burned with fuel to drive an expander and generate electricity. Its advantages include high versatility, no site selection requirements, and high energy density. Disadvantages include high storage tank costs and reliance on chemical fuels.
Currently, adiabatic compressed air energy storage appears to be the most promising technology at present. It has high system efficiency, and my country also has a large number of salt caves and abandoned mines that can be used as gas storage facilities, which can reduce costs to some extent.
Future development direction
Currently, compressed air energy storage is a relatively mature long-term energy storage technology. It also boasts advantages such as minimal pollution, short construction period, and small footprint, giving it broad development potential. It is poised to secure a place in the trillion-dollar energy storage market.
The future development direction is to improve the efficiency of compressed air energy storage, which is currently only around 60%, while pumped hydro storage, also used for long-term energy storage, can achieve an efficiency of 75%. Furthermore, the application of compressed air energy storage is currently limited to the hundreds of megawatts per second level; higher-level compressors are still in the technological research and development stage, and further technological iteration and updates are needed.
Related listed companies
Shaanxi Blower (601369.SH): Founded in 1999, the company's main products are axial compressors, centrifugal compressors, steam turbines, and air separation units. This year, it has completed all the technical solutions for a 300MW-level compressed air energy storage system and compressor units, with the overall efficiency of the multi-cylinder compression system reaching 90%. At the same time, the company has also completed a 50MW-level liquefied air energy storage demonstration project.
Financial reports show that in the first three quarters of 2022, Shaanxi Blower achieved revenue of 8.448 billion yuan, a year-on-year increase of 4.83%, and net profit attributable to the parent company after deducting non-recurring items reached 720 million yuan, a year-on-year increase of 720 million yuan. As of the closing on November 2, Shaanxi Blower was trading at 12.95 yuan per share, with a current total market capitalization of 22.374 billion yuan.
Jintongling (300091.SZ): Founded in 1993, the company's main business is the research, development, production and sales of industrial blowers, compressors, small steam turbines, etc. In 2021, it signed a large-scale centralized compressed air station project with Kaisai Biotechnology, with a total contract value of 309 million yuan.
Financial reports show that in the first three quarters of 2022, Jintongling achieved revenue of 1.251 billion yuan, a year-on-year decrease of 11.84%, and net profit attributable to the parent company of 5.4096 million yuan, a year-on-year decrease of 91.61%. As of the closing on November 2, Jintongling was trading at 3.95 yuan per share, with a current total market value of 5.882 billion yuan.
Dongfang Electric (600875.SH): Founded in 1958, the company's main business is the development, design, manufacturing, and sales of complete sets of power generation equipment for hydropower and thermal power. It has completed the development of the air turbine for the national demonstration project of compressed air energy storage power generation system and is currently advancing the construction of China's first new carbon dioxide energy storage verification project.
Financial reports show that in the first three quarters of 2022, the company achieved revenue of 39.66 billion yuan, a year-on-year increase of 21.53%, and net profit attributable to the parent company after deducting non-recurring items reached 2.135 billion yuan, a year-on-year increase of 37.99%. As of the closing on November 2, Dongfang Electric was trading at 23.26 yuan per share, with a current total market capitalization of 72.543 billion yuan.
Hangzhou Oxygen Plant Group Co., Ltd. (002430.SZ): Founded in 1950, the company's main products are complete sets of air separation equipment, petrochemical equipment, and various gas equipment. It is a leading air separation unit manufacturer in my country, with a market share of 43%, and possesses the capability to produce its own air compressors.
Financial reports show that in the first three quarters of 2022, the company achieved revenue of 9.766 billion yuan, a year-on-year increase of 8.97%, and net profit attributable to the parent company after deducting non-recurring items reached 1.214 billion yuan, a year-on-year increase of 1.962 billion yuan. As of the closing on November 2, Hangzhou Oxygen Plant Co., Ltd. was trading at 42.1 yuan per share, with a current total market capitalization of 41.405 billion yuan.
Koyo Intelligent (002380.SZ): Founded in 1993, the company's main business is the research, development, production, and sales of thermal automation and power plant information products. The world's first 60MW non-combustion compressed air energy storage power station, provided by Koyo Intelligent, has been successfully connected to the grid.
Financial reports show that in the first three quarters of 2022, the company achieved revenue of 900 million yuan, a year-on-year increase of 21.06%, and net profit attributable to the parent company of 62.322 million yuan, a year-on-year increase of 22.56%. As of the closing on November 2, Keyuan Smart Technology Co., Ltd. closed at 14.86 yuan per share, with a current total market value of 3.566 billion yuan.
