The 1020 MW Tala project had to shut down on the morning of 25th June and again on 26th June (today) due to transmission line outages in India.
The transmission lines in India were hit by lightning and bad weather as the region south of Bhutan’s border suffered from heavy rains and winds.
On the morning of 25th June two units of 170 MW each (240 MW) which were operating in Tala automatically shutdown as soon as the line outage in India happened.
Tala has six units in total of 170 MW each (1020 MW) but only two units were operating due to limited water levels.
When the shutdown happened, Bhutan and critical areas like Thimphu and Phuentsholing got most of its power from the 336 MW Chukha project, otherwise Chukha power is normally exported given its higher tariff rate than Tala.
Tala came back online again on the same day as soon as the line in India was switched to accommodate Tala’s power.
Then on 26th June morning the transmission line in India was affected again and this time four units of 170 MW each (total 480 MW) which were in operation in Tala due to increased water levels were all shut down again.
Again, once the line was switched Tala could start producing power again.
The DGPC is yet to do a calculation of the revenue loss but an official said it should not be substantial.
Tala is Bhutan’s biggest revenue earner.
Since most of the rains are in the south the Wangchu river does not have as much water and so power generation is not at the full capacity of six units.
However, the heavy rains in southern Bhutan have impacted the access to Tala’s powerhouse.
Staff in the powerhouse who normally do an eight-hour shift have been stuck in the power house for 24 hours now.
Efforts are being made to clear the road.
A DGPC official said that the staff have adequate food, water and places to sleep as such a situation had been foreseen before.