Huoi Quang hydroelectric power plant, Chieng Lao commune.

Leading us on a tour of the plant, Mr. Ngo Van Chung, the foreman of the Huoi Quang Operation Workshop, introduced: "This is the first underground power plant in the mountains designed and built by Vietnam, with two parallel water diversion tunnels drilled underground in the mountain, 4.2 km long and 7.5 m in diameter. The project has a reservoir with a capacity of over 184 million m³ and a gravity concrete dam, 104 m high, located in Ta Gia commune, Lai Chau province. From 2015 to the present, the Huoi Quang Hydropower Plant has contributed 16.9 billion kWh to the national power grid."

Currently, the plant has 65 staff members, including 45 directly involved in operations, organized into 3 shifts and 5 teams working 24/7; the remainder are in the repair and maintenance department. The staff, engineers, and workers possess high-quality professional skills, meeting the plant's operational needs and ensuring absolute safety for both personnel and equipment, preventing any preventable incidents.

Central control room of Huoi Quang Hydroelectric Power Plant.

The central control room, considered the "brain" of the power plant, is equipped with modern control and monitoring systems. According to Mr. Pham Van Quyet, Head of Operations at the central control room, the room is responsible for controlling, monitoring, and operating all equipment systems in the power generation production line, from the spillway area and the machine room to the distribution substation, through a system of computers and cameras.

Following the tunnel deep into the mountain, we visited the location of the two power generating units and other parts of the plant, and were impressed by this century-long project of the Vietnam Electricity Group (EVN). The workers operate the generating units via a computer-based control system. During operation, the plant emphasizes digitalization, applying technical and safety management software; and maintaining electronic operating logs. Online monitoring systems for the generating units have been installed and upgraded, and the dam monitoring system is connected to the Hydropower Plant Control Center (Son La Hydropower Company) for monitoring.

To ensure safe operation and electricity production, the Huoi Quang Hydropower Plant annually develops a plan to inspect the condition of its structures and equipment, review human and material resources to ensure readiness before the rainy season. It proposes to the company to carry out major repairs and maintenance of the floodgate system, spillway, and hydraulic mechanical equipment of the water intake gates according to regulations. It also organizes disaster prevention drills; and promptly disseminates information about the plant's operation and flood discharge schedule to the communes and villages in the downstream area of ​​the plant...

Thanks to the synchronized implementation of various solutions, from the beginning of the year to July 18th, the electricity output of Huoi Quang Hydropower Plant reached 962 million kWh, an increase of 13.4% compared to the same period last year. The goal is to achieve and surpass 1.58 billion kWh of electricity output by the end of 2025, contributing to the overall electricity output of the entire province.

Huoi Quang Hydropower Plant Power Distribution Station.

Mr. Mai Tong Giang, Director of Huoi Quang - Ban Chat Hydropower Company, said: The company regularly monitors weather and hydrological conditions, and organizes the safe and efficient operation of the Huoi Quang Hydropower Plant's generating units. They strengthen inspection and supervision during operation, promptly detect abnormalities, and focus on repairing and maintaining the technological equipment system, ensuring the generating units operate safely, stably, and with the highest possible availability.

In addition, the company has launched emulation movements, encouraging employees to actively participate in research and propose solutions, initiatives, and technical improvements. In 2024, the company had 3 EVN-level initiatives and 11 company-level initiatives recognized. Many initiatives are currently being applied in the plant's operations, such as: improving the working circuit of the main transformer cooling oil system; renovating the logic circuit of disconnectors 941-3 and 942-3; renovating the outgoing line jumpers of lines 271 and 272; adding overvoltage protection devices to the control equipment of the arc valve... Through these efforts, the company ensures stable operation of equipment systems, increases the reliability availability factor of the generating units, improves working conditions and environment, increases labor productivity, and saves costs in operational management.

With effort, responsibility, and dedication, the staff, engineers, and workers of Huoi Quang Hydropower Plant are working day and night to ensure safe operation of the plant and contribute to bringing electricity to all parts of the country.