Melting Mountains, Fading Power: Upper Tamakosi Feels the Heat of Climate Change


19-March,2023 Kathmandu: Upper Tamakoshi (456 MW), the country’s largest hydropower generation center, is badly affected by climate change.

During the extremely dry season of February-March, the Upper Tamakoshi has been able to produce only 10 to 15 percent of its connected capacity. Purnagopal Ranjith, head of the Project, said that by collecting water throughout the day, up to 300 megawatts are produced in the evening and morning peak (the time when electricity is consumed the most).

According to him, this afternoon, Upper Tamakoshi has produced a total of 15 megawatts. The water level in the Tamakoshi River has become very low and there has been a significant decrease in electricity generation. Currently, only 11 cubic meters per second (cums) of water is available in Tamakoshi River. While the excessive flow of Tamakosi is from 350 to 400 cums.

“By preserving these 11 cumes, we have produced electricity in the morning and evening peak,” said Ranjit .

70 percent of the watershed area of the upper Tamakhoshi falls in Tibet. Ranjith says that the situation is even more dire as the snow in the mountains is less this year. Upper Tamakosi has 6 units of 76 MW each. All these units cannot operate due to lack of water.

According to the design, Upper Tamakosi produces 2291 gigawatt hours (2 billion 291 million units) of electricity in a year. According to the Power Purchase Agreement (PPA) with the Electricity Authority, Upper Tamakosi must produce at least 80 percent of the contracted power. Otherwise there will be a fine.

Due to the drying up of water in the river, it seems that the financial condition of Upper Tamakosi will also be affected. The project has agreed with the Authority at the rate of Rs 3 63 paisa per unit during rainy season and Rs 6 96 paisa per unit during winter season. In other private sector projects, it is Rs 4 80 paisa per unit in rainy season and Rs 8 40 paisa per unit in winter season.

According to the authority’s load dispatch center, the demand for electricity across the country is 33,450 megawatt hours (33,450,000 units) as of today. Out of the total demand, 4484 megawatt hours (4 million 484 thousand units) have been produced from the electricity authority’s own production , and 2634 megawatt hours (2 million 634 thousand units) from the subsidiary company of the authority.

Similarly, 9932 megawatt hours (9 million, 932 thousand units) have been produce from the private sector, and 14080 megawatt hours (14 million, 80 thousand units) have been imported from India. The highest demand in the system is 1812 MW.


Source : Jalasarokar