GUANGZHOU, April 21 (Xinhua) -- China's first 500-kV cross-border alternating-current power interconnection project went into operation on Monday, sharply expanding electricity exchange capacity between China and Laos, China Southern Power Grid Co., Ltd. said.
The China-Laos 500-kV interconnection project raises two-way power transfer capacity between the countries from 50,000 kW to 1.5 million kW, enabling the annual transmission of about 3 billion kWh of clean electricity, roughly 30 times the capacity of previous lines, the company said.
The project, the largest cross-border grid project and the highest-voltage power link between China and Laos, connects southwest China's Yunnan Province with Oudomxay and Luang Namtha provinces in northern Laos.
Cross-border electricity trading began as the project entered operation. About 4.81 million kWh of power from clean energy bases in northern Laos was transmitted to Yunnan through the new line, marking a more regular and institutionalized phase of power connectivity between the two countries.
It is also the first time an overseas new energy project has participated in China's electricity market, the company said. The power involved in the transaction came from a large mountain photovoltaic project in Laos, one of the core supporting power sources for the interconnection line.
The solar project has an average annual power generation capacity of about 1.65 billion kWh. In 2026, it is expected to transmit about 1.1 billion kWh of solar power across the border, supporting energy complementarity between the two countries.
Construction of the interconnection project began on Feb. 26, 2025. Spanning a total length of 177.5 km, the transmission line includes a 145-km Chinese section and a 32.5-km Lao section. The infrastructure was funded and constructed by China Southern Power Grid Co., Ltd. and Electricite du Laos Transmission Company Limited, respectively.
The project is part of an action plan for building a China-Laos community with a shared future. Its launch comes as the two countries mark the 65th anniversary of diplomatic relations and the China-Laos Friendship Year.
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