SUCCESSFUL ENERGIZATION OF THE 500KV LAO CAI – VINH YEN TRANSMISSION LINE, LAO CAI 500KV SUBSTATION, AND CONNECTING 220KV LINES

Lao Cai 500kV Substation

Vinh Yen 500kV Substation

Recognized as one of the key components of the 500kV North–South Transmission Line (Circuit 3), the 500kV Lao Cai – Vinh Yen Transmission Line is a nationally significant energy infrastructure project with a large scale, totaling over VND 7,410 billion in investment. The line spans nearly 230 km with 468 tower foundations across Lao Cai and Phu Tho provinces. In addition, Phase 2 of the Lao Cai 500kV Substation Project, with a total investment of over VND 1,564 billion, has also been completed—including the construction and energization of the 500kV switchyard and 500kV transformers—ensuring synchronous operation with the 500kV Lao Cai – Vinh Yen line.

Switchyard area – Lao Cai 500kV Substation

Switchyard area – Vinh Yen 500kV Substation

For this project cluster, AIT Group was honored to be selected by Power Project Management Board 1 – a subsidiary of Vietnam Electricity (EVN) – as the contractor for several major packages, including:

• Supply of secondary equipment and materials

• Supply and transportation of shunt reactors

• Supply of 500kV power transformers and 500kV shunt reactors

• Supply of primary equipment and materials for the 500kV switchyard

Equipment supplied and installed by AIT Group

Electrical cabinets supplied and installed by AIT Group

The transmission line traverses highly diverse and challenging terrain—high rugged mountains to steep hills and river-crossing areas. Moreover, adverse northern weather conditions this year further increased construction complexity. Despite these difficulties, AIT Group’s engineers and workers remained steadfast on site, implementing a rolling construction method and deploying parallel work teams to ensure progress. With close guidance the Government, the Prime Minister, central ministries, local authorities, mass organizations; the strong involvement of EVN and Power Project Management Board 1; and the unwavering determination of all AIT engineers, staff, and subcontractors, the project cluster achieved:

• September 30: Successful energization of the 500kV Lao Cai – Vinh Yen Transmission Line

• September 29–30: Successful energization of the 500kV Lao Cai Substation (Phase 2) and the 500kV feeder bays at Vinh Yen 500kV Substation

Monitoring screen – Vinh Yen 500kV Substation

Vinh Yen 500kV Substation successfully energized in September 2025

Successful energization at Lao Cai 500kV Substation

The commissioning of this cluster of nationally critical energy projects in October 2025 not only plays an essential role in transmitting large power capacity the Northwest to the Northern power grid and the national system, but also stands as a profound source of pride for all engineers, employees, and workers who have dedicated months of relentless effort on site. This achievement also serves as a meaningful tribute to the 71st Anniversary of Hanoi’s Liberation Day (10/10/1954 – 10/10/2025) and to the 14th National Congress.