PowerChina has successfully completed the water-fill test for the molten salt storage tanks at the Amdo solar thermal project in Xizang, marking a key step toward full-capacity grid connection for the world's highest-altitude tower-type solar thermal plant.

The Amdo project, a key energy initiative under Tibet's 14th "Five-Year Plan", is located about 17.5 km east of Pana township in Amdo county, Nagqu city, at an altitude of 4,645-4,657 meters.

It is the world's first solar thermal power station built under the combined challenges of ultra-high altitude, ultra-low temperatures and an extremely weak power grid.

The 100 MW plant uses molten salt tower technology with an 8-hour thermal storage system, featuring a heliostat field of 800,000 square meters across 15,927 mirrors capable of precise sun-tracking.

The molten salt storage tanks, described as the plant's "super energy storage hub", use a high-low temperature dual-tank system that determines the station's ability to store energy, regulate peak loads and maintain stable round-the-clock power generation.

The tanks feature a large-volume circular dome design with a nominal diameter of 30.8 meters, a tank height of 15 meters and a maximum molten salt storage capacity of 20,000 tonnes.

The water-fill test, a critical pressure verification procedure before large tanks are commissioned, passed successfully on the first attempt, laying the foundation for subsequent molten salt injection, salt melting and temperature commissioning, and on-schedule power generation.

Once operational, the Amdo project is expected to generate 260 GWh of clean electricity annually, saving 60,000 tonnes of standard coal and reducing carbon dioxide emissions by approximately 165,000 tonnes per year.