China Energy Investment Corp (CHN Energy) has brought all three units of the first phase of the Shuangjiangkou hydropower station into commercial operation, the company said on Aug 31.

Located in Aba prefecture, Sichuan province, the Shuangjiangkou station features a 315-meter dam, the tallest in the world. The plant has a total installed capacity of 2 GW, comprising four 500 MW Francis turbine-generator units, with a reservoir capacity of 2.9 billion cubic meters. It serves as a key control project on the upper Dadu River, providing flood control, power generation and water regulation.

The station is a key national clean energy project under China's 14th "Five-Year Plan" and a major western development initiative, with total investment exceeding 36 billion yuan. Beyond the world's tallest dam, the project set multiple industry records, including the highest ground-stress powerhouse among similar domestic projects, the world's largest-capacity hydraulic hoist and the largest cross-section flood discharge tunnel in global hydropower.

Planning for the project dates back to 1977, when the Ministry of Water Resources and Electric Power initiated the Dadu River development plan. The name "Shuangjiangkou" was adopted in a 2003 plan revision, the project received state approval in 2015, dam filling began in April 2020, first reservoir impoundment was completed in May 2025, and the first unit was connected to the grid in June 2026.

Since the first unit began operation, the construction team has commissioned three units within two months to meet summer peak power demand in the Chengdu-Chongqing economic zone, delivering 500 GWh of clean electricity and strengthening summer power supply security for Sichuan province and the broader region.

Once all units are operational, the station will generate about 7.7 TWh annually, replacing 2.96 million tonnes of coal and cutting carbon dioxide emissions by 7.18 million tonnes per year. It will also boost downstream cascade power generation by 6.6 TWh annually, improving water resource utilization across the Dadu River basin.

One unit remains to be commissioned, after which all four units will operate at full capacity.