In Delingha, Qinghai in April, the cold wind is still piercing. On this plateau at an altitude of nearly 3000 meters, rows of huge curved mirrors are quietly following the sun. This is the CGN photothermal test base. In the just passed winter, a set of "super equipment" withstood the test of severe cold and strong winds - the world's largest (8.6 meters) molten salt trough collector independently developed by China, which heated the molten salt to 574 degrees Celsius in extremely cold temperatures of minus 23 degrees Celsius and level 9 winds, and stably output electrical energy.

This marks that China has fully mastered the core technology of molten salt trough heat collection and is no longer subject to others, "said the on-site engineer pointing to the 182 meter long array of heat collectors. The successful verification of this equipment not only means that China's solar thermal power generation has its own "heavy equipment", but also makes the large-scale use of solar energy for long-term energy storage and peak shaving a reality.

The Super Mirror on the Gobi Desert

This test platform located in Delingha is currently the largest standard molten salt trough collector testing system in the world in terms of opening size. It consists of four large arrays of collectors, each with a length of 182 meters, an opening width of 8.6 meters, and a total effective heat collection area of approximately 5970 square meters. From a distance, it looks like several huge 'super mirrors' on the Gobi Desert.

Compared with traditional thermal oil systems, this new equipment uses molten salt as the heat transfer medium, achieving three major performance leaps:

Huge temperature difference: It can achieve stable operation from 290 ℃ inlet to 550 ℃ outlet, with an energy storage temperature difference of up to 260 ℃, which is 2.6 times that of traditional thermal oil systems. A larger temperature difference means that the same volume of molten salt can store more heat, greatly improving power generation efficiency.

Strong spotlight capability: Its geometric spotlight ratio reaches 107.5 times, which can more efficiently capture and focus solar energy.

Excellent weather resistance: Since its commissioning in December 2025, it has undergone typical working conditions such as winter solstice and spring equinox. Third party testing shows that its optical efficiency and heat collection efficiency have both reached the design values, proving the structural safety and operational stability under extreme weather conditions.

From following to leading

Solar thermal power generation is known as the "stabilizer of the power grid" because it can store solar energy in the form of heat energy and generate electricity continuously at night or on cloudy days. However, in the past, the core technology of large-scale trough collectors has long been monopolized by foreign countries, especially the problems of high-temperature molten salt anti condensation and large opening structure design, which have been restricting the large-scale development of China's solar thermal industry.

The 8.6-meter complete set of equipment validated by CGN has achieved 100% localization of key equipment such as brackets, flexible connection components, and controllers. This not only breaks the technological blockade, but also drives the upgrading of the domestic high-end equipment manufacturing industry chain. From laying out the solar thermal business in 2011, to building China's first large-scale commercial solar thermal demonstration power station, and now mastering the world's largest open technology, China's solar thermal industry has completed a leap from "following" to "running in parallel" and then to some "leading".

The Chinese solution for photothermal technology

The success of technical verification has directly accelerated the pace of engineering applications. At the beginning of April this year, the 50 MW project of CGN Umatang in Xizang, the world's highest trough solar thermal power station, was officially started. The project site has an altitude of 4550 meters and will be the first commercial application of this 8.6-meter large open slot collector. Compared with the traditional 5.77m collector, its condensing ratio is increased by about 18%, and the unit power generation cost is reduced by about 10%, which will provide an extremely valuable stable clean power supply for Xizang power grid.

At the same time, China's solar thermal technology is also actively "going global". From the Noor III project in Morocco, to the Redstone power station in South Africa, and to the Maktoum Solar Park in Dubai, Chinese made solar thermal equipment is shining brightly in the sunshine of the Middle East and North Africa. These projects not only output green electricity, but also China's standards and solutions in the field of new energy.

Hu Guangyao, Secretary of the Party Committee and Chairman of CGN New Energy Holdings Co., Ltd., stated that the next step will be to accelerate the engineering promotion of this complete set of equipment, providing more solid technical support for China to build a new power system and build an energy powerhouse. Against the backdrop of carbon peak and carbon neutrality, the "path of solar thermal energy" independently paved by the Chinese people is becoming wider and wider.

(Note: The data in the article are all from the official release and public technical verification reports of CGN.)Editor/Yang Meiling