Lacking water, Thac Ba hydropower plant operates moderately

On April 25, information from Thac Ba Hydropower Joint Stock Company, the water flow to Thac Ba lake this year is lower than in previous years. Therefore, from the beginning of the year until now, the plant has been operating moderately, with the generating units taking turns generating electricity.

According to the plan, the water flow to the lake in 2024 must reach 175.3 m3/s, but the average in the first quarter of 2024 will only reach 73.4 m3/s. The water level in Thac Ba Lake is currently about 53m, compared to the same period last year which was 48m.

Reporters were present at Thac Ba hydroelectric lake – Thac Ba Hydroelectric Plant (Yen Binh district – Yen Bai province) in the last days of April. This plant has a capacity of 120 MW, contributing significantly to the electricity generation. national power grid in general and for the North in particular.

Actual records show that prolonged hot weather causes upstream water flow to the lake to be very low. The road leading down to the hydroelectric lake used to be dozens of meters underwater, but now people can comfortably walk on dry concrete blocks. A series of tourist boats on the empty lake.

Downstream, one can easily see the river bottom drying out, revealing undulating rocky outcrops.

According to the capacity of each unit is 40MW, however, due to having to operate alternately due to lack of water, in the first quarter of 2024, electricity output only reached more than 82 million kWh compared to 138 million kWh in the same period of 2023.

Previously, in June 2023, due to the low amount of water entering the reservoir and the reservoir water level being close to the dead water level, Thac Ba Hydropower Joint Stock Company had to proactively stop 2 generating units from generating, and unit 3 continued to generate electricity at the minimum level. (15MW) to provide water for downstream areas and provide electricity for people’s lives. Even by early July last year, almost all generating units had to stop operating because of insufficient water.

“Normally, this time every year there are small floods, so the average amount of water flowing into the lake is about 100 m3/s. Currently, even though it is near the end of April, there has not been a flood, so the average daily amount of water entering the lake is about 31 m3/s,” said Mr. Nguyen Manh Cuong – Deputy General Director of Thac Ba Hydropower Joint Stock Company.

Mr. Cuong assessed that due to El Nino (a natural phenomenon in which ocean temperatures increase) lasting, it is predicted that this year the amount of water will be about 30% less than the average for many years. If this weather phenomenon continues beyond June, it will greatly affect the company’s electricity production and business activities. Even continuing to produce electricity will risk losses.

It is forecasted that this year, the hydroelectric production situation will be extremely difficult. In 2010 and 2016, there was a time when the lake water level also dropped but still reached 46m. In 2023 alone, the water level has dropped to the lowest in the plant’s history.

“According to the plan, this April, we will have to produce about 35 million kWh of electricity. But up to now, it has only achieved more than 6 million kWh. And by the end of the month, it reached about 10 million kWh, which is less than 1/3 of the plan,” Mr. Cuong said.

Deputy General Director of Thac Ba Hydropower Joint Stock Company emphasized that the amount of water flowing into the lake is mainly to regulate water to ensure minimum flow, hydroelectric plants operate to generate electricity using the flow of water. Some plants in other areas have now had to stop to ensure the safety of the generating units when operating with flow and water head below design.

Currently, implementing instructions on saving water to ensure electricity supply for the dry season, the factory only releases water twice about 500 million m3 to serve agricultural production, compared to 3 times about 700 million m3 like usual. year.

“The factory’s operations this year are extremely difficult, so we can only wait and hope for the hydrological situation to improve production,” Mr. Nguyen Manh Cuong shared.