Lhasa Dangxiong, Umatang Township. On the plateau meadow at an altitude of 4550 meters, mechanical roar cuts across the sky. On April 6, CGN's 50 MW solar thermal project in Wumatang, Xizang officially broke ground. This not only breaks the altitude record for global trough solar thermal power stations, but also marks the first commercial application of China's fully independent intellectual property rights 8.6 meter large opening trough collector. As the core of the Dangxiong Umatang solar thermal+photovoltaic integrated project, it is equipped with 6-hour molten salt thermal storage, which will completely solve the problem of photovoltaic night power outage and provide stable and clean electricity for snowy plateaus.

The 'Super Mirror Array' on the Plateau

Building a solar thermal power station on the "Roof of the World" with thin air and strong ultraviolet radiation is itself a technological extreme challenge. The project site has an altitude of 4550 meters, with low average annual temperature and large temperature difference between day and night, which puts extremely high demands on the weather resistance of the equipment. The project adopts thermal oil tank photothermal technology, with a collection mirror field area of 242000 square meters, equivalent to the size of 34 standard football fields. The mirror field consists of 68 circuits, of which 8 circuits are the first to use the 8.6-meter large open slot collector independently developed by CGN, and the remaining 60 circuits use 5.77-meter collectors. This 8.6-meter collector is currently the slot type collector with the largest opening size in international commercial applications. Its concentration ratio and energy flow density have increased by 18% and 17.5% respectively compared to the 5.77-meter model, and the unit power generation cost has been reduced by about 10%, achieving a leap from technology introduction to independent innovation in core equipment.

Molten salt thermal storage to fully charge the night

Photovoltaic power generation relies on the weather to generate electricity, and cannot provide power at night or on rainy days, while the core advantage of solar thermal power generation lies in energy storage. The project is equipped with a 6-hour molten salt thermal storage device and a 20 MW electric molten salt heater, which absorbs solar energy during the day and stores excess heat in the molten salt. At night, the thermal storage system releases energy to continue generating electricity, achieving 24-hour continuous and stable output. This integrated design of "photothermal+photovoltaic" provides a "power bank" for intermittent photovoltaic power generation. The integrated project has a total installed capacity of 450 megawatts (50 megawatts of solar thermal and 400 megawatts of photovoltaic), and is planned to be fully put into operation in 2027. The photovoltaic part has started construction in September 2025, adopting the complementary mode of animal husbandry and photovoltaics to achieve the coordinated development of power generation and ecological animal husbandry.

Green benefits and people's livelihood temperature

According to calculations, when the Xiongwumatang integrated project is fully completed, it is expected that the annual average on grid electricity consumption will be about 719 million kilowatt hours, which can meet the annual electricity demand of about 600000 households. In terms of environmental protection, about 216900 tons of standard coal are saved and 652300 tons of carbon dioxide are reduced every year, which is of great significance to protect Xizang's green water and green mountains. At the level of people's livelihood, although the construction of the project is limited by the high-altitude climate (the effective construction period is only from April to October), it has cumulatively driven more than 2000 local employment opportunities and brought more than 5.2 million yuan in economic income to the local area through labor and equipment. The project also provides professional skills training to help farmers and herdsmen transform into skilled workers, injecting real livelihood warmth into the plateau.Editor/Yang Meiling