China Tests Largest Liquid Salt Collector, Solar Thermal Driven to Large Scale

Aerial photo of a solar thermal power project in Jinta, Gansu Province. (CAO HONGZU - FOR CHINA DAILY)

China announced a new breakthrough in the concentrated solar power (CSP) sector, namely a solar plant that concentrates solar heat to generate electricity. According to a report by China Daily quoted on Tuesday, April 21, China has successfully verified the world's largest liquid salt trough collector system, a step that is said to be important to encourage CSP projects on a large scale.

The project developer, China General Nuclear Power Corp (CGN), said the validation was carried out on equipment and processes for a liquid salt trough collector with an opening of 8.6 meters. This size is said to be the widest in the world. Testing was carried out at CGN's test facility in Delingha, Qinghai Province, northwest China.

CGN assessed that these results show that China has mastered the core technology of liquid salt trough collectors. In the CSP project, this technology is important because the accumulated solar heat can be stored for longer, then used when electricity demand rises or when sunlight decreases.

Unlike ordinary solar panels that directly convert light into electricity, CSP works by reflecting and concentrating the sun's heat into a single collecting system. In this project, the heat is stored using molten salt. Therefore, this technology is considered to have two functions at once, namely to help supply electricity during peak loads and to become a long-term energy storage.

The Chinese government targets CSP installed capacity to reach around 15 million kilowatts by 2030. The target is listed in guidelines released by the National Development and Reform Commission and the National Energy Administration at the end of 2025.

Head of CSP technology expert at CGN, Yin Hang, said the pilot platform consists of a trough collector system, a heat storage system, and a steam generation system. According to him, in terms of the size of the opening, this facility is currently the largest standard liquid salt trough collector test system in the world.

CGN is not a new player in the sector. Since entering the CSP sector in 2011, the company has built the first large-scale commercial CSP demonstration plant in China, as well as the largest single-tower CSP project in the country.

The company said it would continue to refine technology and research to accelerate the use of large-scale liquid brine trough equipment. This development shows that China is not only developing solar panels, but also thermal solar technology that can store heat for use when electricity supply is needed.