Hydropower reservoirs have been under severe water shortages despite low capacity utilization of hydropower plants, and/or even complete shut down for several months. It is forecast that the electricity sector will have to mobilize its high priced fueled generation in the coming months to ensure electricity supply.
Low capacity utilization of many hydropower plants
Talking to our reporter, Mr. Le Dinh Ban, the deputy director of “A Vuong” Hydropower JSC (Quang Nam) said that, due to the effects of El Nino, the drought is forecast to last till June this year, many reservoirs in the Central region and Central Highlands are not fed with flood. Specifically, for the A Vuong company, from December 8, 2015 up to now the company had to cease the generation entirely to lowest volume of water. "By March 10, 2016, the water level in the lake is still lower than its designed setting as many as 4.6 m. Many other hydroelectric reservoirs are in shortage of water. And the hydro power plants have to stop operation, thus the electricity sector has to lake water shortage. Many factories were shut down and the power industry has to generate electricity from oil fueled generators, in counterweight for the shortage of electricity due to inoperative hydropower plants" said Mr. Ban.
In Mr. Ban’s reflection, the water inflow is only 8-10m3/s. For an optimistic expectation, by March 21, the A Vuong Hydropower reservoir would be fed with the water level of 372.7m, sufficient for resumed operation. Otherwise, it is to wait until April 1st before the re-operation. The inflow is too little, by March 10, the output is calculated to reach 3.9 million kWh, accounting for only 0.74% of the assigned production plan.
The production plan of 539 million kWh in 2016 assigned by the Electricity corporation will not be possible. "Currently, the company shuts down but it costs to maintain the organization. If the situation is prolonged, the company has to borrow money from banks to pay salaries to its workers and employees during the outages. Given this stricken situation, it is difficult to estimate the economic consequences for the unit, meanwhile the influence of El Nino will not end until the second quarter as in weather forecast" Mr. Ban said.
"With the on-going activities, during this dry season, the electricity sector will have to resort to oil-fueled generation for 2.5 billion kWh to be produced.”
According to Deputy Director of the Se San Hydropower Company, Mr. Nguyen Dang Ha, in 2016 the company is assigned to produce an electricity output of 1,341 billion kWh. However, in the current hydrological situation, it is difficult to achieve this planned output. For the past three months, the average flow of the Se San 4 reservoir has decreased consecutively. As of December March 9, the Se San 4 hydropower reservoir water level is 210 m, equalized with the dead level. Currently, the Se San 4 (Gia Lai) Hydropower plant operates by discharging water from hydroelectric reservoirs of Pleikrong and Ialy reservoirs. The Ialy and Pleikrong hydropower reservoirs have low level, 3.3 m3 lower than operative elevation. It is generally calculated that the total amount of water shortages in the reservoir is 492.3 million m3, a shortfall of about 28% of designed capacity for reserve during the dry season.
"In the trend forecast, water in reservoirs is insufficient to discharge downstream which is 195 m3/s during the dry season. The company has reported to Kon Tum Provincial People's Committee, Gia Lai Provincial People's Committee and the Ministry of Natural Resources and Environment on the situation of water shortage, and proposed discharge on downstream to maintain the flow till the end of dry season, " Mr. Ha said.
In Phu Yen, according to Mr. Dang Van Tuan, General Director of Ba Ha River Hydropower JSC, the water inflow is only about 35% - 40% of the average level of many previous years. By the end of December 2015, the water level only reached 102,65m. The inflow for hydro reservoirs is not sufficient to maintain water level, the Phu Yen Provincial People’s Committee had to require the flow to be regulated and the operating time of the plant to be set in favor of water supply for production and the domestic consumption.
The Deputy Director of Buon Kuop Hydropower Company, Mr. Nguyen Tan Triet said that since September 2015, hydropower reservoir level of Buon Tua Srah had been down nearly at the dead level, and the situation had not been improved so far. With the very low inflow in the reservoirs of Buon Kuop and Srepok, on March 7th 2016, the Company authorized the power plants to separate from the electricity market, to enable the company to be more active in meeting the demands of drinking water and irrigation for agricultural production in downstream during the dry season 2016. "If the Buon Tua Srah reservoir is utilized with discharge flow of 50 m3/s/ every day in the context of the lake water feeding of only 10 m3/s, the lake will only last 3 months. Therefore, the power supply is very stressful for the dry season" said Mr. Triet.
High priced electricity generation shall be resorted to in order to ensure electricity supply
At the recent meeting with the provincial electricity authorities on options for new power supply during the dry season, Mr. Nguyen Duc Cuong, Director of the National Load Dispatch Center (A0) revealed that as a result of the El Niño impact the hydrological activities have not been favorable for of hydropower reservoirs in the country. Especially the lakes in the provinces southward of Thanh Hoa. Statistics show that the total amount of lacked water accounts for 40-60%, as to compare with the average of many other years, and a number of lakes during the rainy season did not have floods to flow in. So far, many lakes fail accumulating the required water, which should be up to the normal volume, as well as the minimum level required at beginning of the dry season as prescribed by the procedures for regulating the reservoir. National Load Dispatch Center (A0) had to mobilize the resources of expensive power generation, to limit the water intake and storage for hydropower plant operation.
The information from the National Load Dispatch Center (A0) also revealed that at present time, there are 27 large and small hydropower reservoirs in the northern region under unprecedented shortage of water. Among them some large hydro lakes lack huge volume such as Lai Chau, Ban Chat; Son La; Peace; Thac Ba; Ban Ve ... Many hydropower plants had to stop the operation. Dai Ninh hydropower plant is one of them, with no inflow flood, the water level is much lower than the average level, as low as at the alert level. It has been accumulating water continuously for many years just to reach 39% of the required amount of water for running the turbines.