In a remarkable achievement for renewable energy, China Energy Construction Group Co., Ltd. has successfully launched the "Nengchu No. 1" project, the world's first 300-megawatt compressed air energy storage (CAES) demonstration power plant. This groundbreaking milestone represents the largest capacity for a CAES facility globally, setting three new records in terms of unit power, energy storage scale, and conversion efficiency. The project is significant not only for its technical prowess but also for its 100% domestically produced key core equipment, marking a pivotal moment in the commercialization of China's CAES technology.

The necessity for energy storage solutions has never been more pronounced, particularly in the wake of the growing integration of renewable energy sources such as wind and solar. These resources, while abundant, come with inherent variability, leading to periods of both surplus and shortage in electricity supply. This fluctuation necessitates an advanced storage system, aptly described as the “green energy steward,” to maintain a balance within the power grid. It is this context that underscores the importance of systems like the CAES being developed by China Energy Construction.

At the core of the CAES technology lies a sophisticated system comprising various components, including a compression system, thermal storage system, gas storage system, expansion system, and generation system. The process begins when excess electrical power during low-demand periods drives a compressor that compresses air into a high-pressure state, analogous to inflating a bicycle tire. This compressed air is stored in sealed facilities such as salt caverns or artificial chambers, while the heat generated during the compression is stored in large thermal energy tanks on the surface, using mediums like hot water or molten salt.

As Li Jun, the Deputy General Manager of China Energy’s Digital Technology Group, explains, the CAES system utilizes surplus electricity during off-peak times to store compressed air, which can then be released during peak demand to generate power. This mechanism allows for greater stability and reliability in energy supply, effectively mitigating the challenges posed by the intermittent nature of renewables. The "Nengchu No. 1" project showcases the ability to store energy for eight hours and release it for five hours each day, boasting a lifespan exceeding 30 years.

The construction of a CAES facility occurs at a much quicker pace compared to traditional pumped hydro storage systems, which can take from six to eight years. With construction durations of only around two years, CAES provides a comparative advantage in terms of scalability, operational lifespan, cost-effectiveness, and efficiency. It is often referenced as a "super green power bank," with additional benefits including large unit capacity, excellent system stability, robust grid-adjustment capabilities, high energy conversion efficiency, and flexible site selection.

As Wang Mingzhong, the Chief Expert and Chairman of China Energy, elucidates, the capabilities of “Nengchu No. 1” allow it to effectively serve as a partner for renewable energy sources, enhancing grid stability with three times the peak-shaving capacity of traditional thermal generators of similar size. The essential features of long-duration energy storage offered by the CAES technology represent a critical support mechanism for the construction of a new power system in China, contributing significantly to both the resilience and stability of the grid while facilitating the absorption of renewable energy.

The acceleration of CAES technology commercialization in China is a direct result of supportive policies and a growing market appetite, leading to a notable race from initial development to a leadership position in this field. Previously modest projects ranging from 1.5 MW to over 60 MW have paved the way for groundbreaking advancements, culminating in the recent surge to a 300 MW single unit power output.

Li Jun highlights the unique contribution of the "Nengchu No. 1" project; while most operating salt cavern CAES plants around the globe require natural gas for air heating—a process that leads to emissions—the Chinese innovation employs a non-combustion technique to achieve zero carbon emissions. This is achieved through an internal circular process that captures and reuses heat, thus eliminating reliance on external energy sources and associated emissions.

As the technology matures and economies of scale begin to manifest, the return on investment for CAES projects has gradually improved. This not only promises stable economic benefits but also energizes the entire upstream and downstream industrial chain, fostering the development of a new industrial cluster encompassing system research, equipment manufacturing, power station construction, and system operation and maintenance.

Moving forward, China Energy has strategically positioned itself for significant growth in the CAES sector, particularly around large-scale new energy bases like Shagehuang and offshore wind farms. Notably, there are currently over 50 CAES projects either under construction or poised for implementation across various locations, including Gansu Jiuquan, Shandong Tai'an, Shaanxi Tongchuan, and Qinghai Hainan.

Chairman Song Hailiang emphasizes the importance of continuous technological innovation in CAES to further enhance efficiency, reduce costs, and scale up capacity. He anticipates rapid development in regions with high electricity demand in East and Central China, leveraging abundant salt cavern resources to build up storage bases in locations like Echeng, Heze, and Qianjiang. This approach aims to resolve the challenges of large-scale renewable energy storage and distribution while optimizing energy resource deployment for greater efficiency and effectiveness, ultimately stimulating new growth in the renewable energy sector.