Hydropower is the largest contributor to the government revenue. And with plans to generate 10,000 megawatts of electricity by 2020, the revenue is going to increase manifold. However, with global warming imminent, how sustainable will Bhutan’s hydropower projects be?
With rise in temperature, experts say glaciers in Bhutan are retreating at an alarming rate annually. The Chief Glaciologist with the Department of Geology and Mines, Karma, said debris covered glaciers are receding at an annual rate of 30 to 35 metres. “The clean type of glaciers, which are more sensitive to the impact of climate change are receding at around eight to 10 metres annually.”
At this rate of retreat, concerns are being raised on the flow of Bhutan’s mountain rivers. Do the rivers in Bhutan depend on glacial? The Director General of the Department of Hydropower and Power system, Yeshi Wangdi, said there had been no studies carried so far.
“But from the similar studies that we have carried out in the region we can say that the contribution from the glacial to the flow volume of the rivers, it could range anywhere from 5 to 15 percent,” he said adding that it is not a major concern, at least for now.
According to a preliminary study carried out by experts from Norway, till 2070 there will be an increase in river flow due to melting of glaciers. The flow will reduce thereafter. “I think we should not worry so much because as you know that economy life period of any hydro project is around 35 years,” said the Director General. He said by 2070 every project would have earned all the returns and profits.
There are 677 glaciers and over 2,600 glacial lakes in the country.
