The sintering process can generate over 70m kWh yearly, earning about 30m yuan, the firm said
This undated file photo provided by the Nuclear Power Institute of China under China National Nuclear Corporation shows an interior view of the main power generation plant of Chaotan One in Liupanshui City, southwest China’s Guizhou Province. PHOTO: XINHUA
A set of supercritical carbon dioxide (CO2) power generation units commenced commercial operation on Saturday in Guizhou Province, southwest China, marking the country’s pioneering commercial application of this innovative technology.
The unit now in commercial operation, located at a plant operated by Shougang Shuicheng Iron and Steel (Group) Co., Ltd. in Guizhou’s Liupanshui City, constitutes a demonstration project for supercritical CO2 power generation technology utilizing sinter waste heat, according to its developer, the Nuclear Power Institute of China under China National Nuclear Corporation (CNNC).
The project is named Chaotan One, and each unit of the project boasts a power generation capacity of 15 megawatts.
“The project highlights the use of supercritical CO2 power generation technology — an innovative power generation technology characterized by high efficiency, a compact system, fewer auxiliary systems, and faster response speed,” said Huang Yanping, CNNC chief scientist and chief designer of Chaotan One.
“Commercial operation of this project marks a milestone, representing the first transition of this innovative technology from laboratory to commercial implementation in the world,” Huang added.
Innovative power technology
Globally, unremitting efforts and explorations have been made to generate power. So far, the principle of power generation via thermal power, nuclear power, or various waste-heat steam power is similar to “boiling water”: heat water into steam, drive the turbine to rotate, and generate electricity, according to Huang.
“The supercritical CO2 power generation is an innovative thermoelectric conversion technology,” Huang said.
He explained that when the working pressure of CO2 exceeds 73 atmospheres and the temperature exceeds 31 degrees Celsius, it enters a supercritical state.
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Then, CO2 exhibits increasing density, approaching a liquid state, which enables it to store more energy. Meanwhile, its viscosity remains very low, close to that of a gas, resulting in smaller flow resistance.
Huang illustrated this with an analogy: “It’s like a strong man riding a bicycle coated with lubricating oil, allowing him to pedal effortlessly over long distances.”
Compared to conventional sintering waste-heat steam power generation technologies, Chaotan One has increased power generation efficiency by over 85 percent, net power generation by over 50 percent, and reduced the required floor space by 50 percent.
Under the current sintering process, the project can generate over 70 million kilowatt-hours of electricity annually, adding about 30 million yuan (approximately 4.26 million U.S. dollars) in revenue, according to Shougang Shuicheng Iron and Steel (Group) Co., Ltd.
Huge potential
The Nuclear Power Institute of China embarked on research into the world’s cutting-edge supercritical CO2 power conversion technology in 2009. In 2023, construction commenced on its demonstration project in Liupanshui.
Beyond being an innovative technology, supercritical CO2 power generation is poised to significantly contribute to the country’s dual carbon goals by efficiently converting industrial waste heat into power.
“Aside from waste heat power generation, this technology holds even broader application prospects,” Huang remarked.
He added that this technology helps break through the technical bottleneck of efficient utilization of medium- and small-scale power sources and medium- and high-temperature heat sources worldwide.
In 2024, CNNC launched a demonstration project integrating molten-salt energy storage and supercritical CO2 power generation technologies, with scheduled demonstration operations set for 2028.
“Looking ahead, the supercritical CO2 power generation technology will be integrated with multiple heat sources to form power generation systems, expanding its applications to solar thermal power, waste heat recovery, energy storage, and other fields,” Huang said.
