Pema Tshomo, Thimphu
Snowfalls in Bhutan are occasions for people to celebrate, with children and families making best use of it as a day of entertainment. However, snowfalls are a major contribution to the country, as it contributes immensely to the amount of hydropower generated and thus revenue earned.
Records with the Department of Hydro Met Services show that the snowfall of March 11, 2017, has been the heaviest one in the last decade. Thimphu and Paro recorded seven inches of snow each while Bumthang recorded 1.8 inches. The highest was in Gasa with 11.4 inches.
Speaking to The Journalist, Dasho Chhewang Rinzin, Managing Director (MD) of Druk Green Power Corporation (DGPC) said that there will definitely be an increase in generation due to the snowfall. However, Dasho said that it is difficult to put a figure on the additional generation that is attributable to the snow. “The snow is still melting and we might be able to make a guesstimate in a week or two,” Dasho said.
Dasho added that snowfall is always good for hydropower projects. “Snow and glaciers at higher altitudes like mountains, act as reservoirs for water that flow down to the generating plants as and when the snow and glaciers melt. The only negativity is in the event of a glacier lake outburst that could lead to a flood,” he said. However, Dasho underlined that the dams are designed to cater to the additional discharge due to glacier lake outbursts.
Dasho highlighted the difference between precipitation in solid and liquid forms. “Snow stores water and releases it when it melts. If there is less snow and more rain, there is less chance to store water for later use,” he said, while elucidating the need for preserving uphill forests and wetlands.
He also said that generation is directly proportional to the quantum of water and the design head. The more the quantum of water and higher the head, the more electricity a hydropower plant can generate. For the same amount of water, Tala power plant can generate almost double the electricity due to the higher head.
Dasho reiterated that DGPC is definitely expecting additional generation due to the snowfall. “This would cater to by which, it would result in higher levels of availability of energy for the domestic market and sale of surplus power to India, which further would bring in higher revenues in proportion of the increase in generation.
Hydropower is the highest revenue generator of Bhutan. The country has a potential to generate about 30,000 mega watt (MW) of power. Till today, 1480 MW is being generated. Close to 75 percent of the power generated is exported to India. In 2015, 7,747.17 MU of energy was generated. Hydropower exports provide more than 40 percent of Bhutan’s revenue, and constitute 25 percent of its GDP. Another 25 percent contribution to the GDP comes in the form of hydropower infrastructure construction.