KATHMANDU, Dec 25: Electricity generation has resumed partially at the 456 MW Upper Tamakoshi Hydropower Project (UTKHPL), the largest of the hydropower projects operational in Nepal after an 88-day shutdown.
Partial repairs were carried out on the damaged structures caused by landslides and floods triggered by the continuous rainfall on September 27 and 28, and electricity generation was resumed on Tuesday evening at 7:40 pm, after 88 days. Currently, the project is generating 120 megawatts of electricity by fully utilizing the available water flow in the river, which has been integrated into the national transmission system.
Due to continuous rainfall, the water flow in the Tamakoshi River increased and the electricity generation from the central station was halted from 7 pm on September 27. The landslide had caused damage to the control room building located to the right and slightly below the dam site, the sand settling pond (desander), and the underground canal (culvert) that carries water from the dam to the desander.
The road was blocked due to the fall of a large stone on the 300-meter access road section leading from the power station at Gongar to the dam site at Lamabagar. The rocks were removed using explosives to clear the road. Additionally, the 220 kV Gongar-Khimti transmission line which transmits electricity produced at the UTKHPL, was damaged due to rainfall at tower number 46 located at Singti.
All units of Upper Tamakoshi connected to national grid
In one of the two transformers, partial repairs of the left-side transformer were completed, and electricity production was started one day before the scheduled time. The old slope of the wall of the partially damaged transformer was demolished and repaired. Similarly, grouting has been done to repair the cracks observed on the wall and ceiling of the culvert.
The Desander damaged by the landslide has been partially repaired and the upper Tamakoshi has come into operation for the time being. The rest of the desander is undergoing maintenance. After the completion of the work, water can be stored during times of low electricity demand, and it can be used to run the UTKHPL at full capacity for four-hours during peak demand periods in the morning and evening. The UTKHPL is being renovated so that it can be used during peak hours in Mid-December to Mid-January (Poush).
Kulman Ghising, managing director of Nepal Electricity Authority (NEA), who is also the chairman of the board of directors of Upper Tamakoshi Hydropower Ltd, the promoter company of the hydroelectric power station, said that the team including members of the board of directors of the company, the chief executive officer (CEO) conducted a site inspection on December 3 and set a schedule to complete the maintenance by December 25 and begin electricity generation.
NEA MD Ghising said that due to the continuous efforts of the company’s board of directors, management, consultants and builders, the maintenance of the upper Tamakosi was completed and the power generation started a day ahead of schedule.
“Stones and debris were piled up in the de-sander and due to the landslide, two employees of the company and two soldiers on security duty lost their lives. The employees present at the site were fearful,” Ghising said, “There was no access road to the place, and the power supply was cut off. In such a situation, it was very challenging to proceed with the maintenance. However, with everyone’s support and cooperation, we have completed the maintenance and partially succeeded in producing electricity.
Ghising further said, “Due to the closure of the country's largest power plant, there was discomfort in power supply management. With the partial start of power generation from the UTKHPL, the balance of power imports from India will be eased in peak time power supply.”
The CEO of the company, Mohan Prasad Gautam, said that suggestions received from the company's board of directors and expert groups for operating the power plant were incorporated. Measures for maintenance and repairs were implemented, and work was carried out with a planned approach. We were able to produce electricity before the scheduled date through regular monitoring.
CEO Gautam said that a tender has been called for the selection of construction contractors to repair the other descender on the right before the start of the next rainy season.
Since the entire structure of the hydropower plant is insured, the maintenance cost of the damaged structure will be borne by the amount received from the insurance. The company had made an initial insurance claim of Rs 1.78 billion for the damage caused by the landslide.
The company and National Insurance Company Limited are jointly assessing the damage. Once the work is completed, the insurance amount will be paid. Similarly, the income received from the sale of electricity has been insured for three months. Under the terms and conditions mentioned in the insurance contract, the company will receive the payment of two months income.
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