
Prime Minister Narendra Modi has been saying to Nepal and others that Bhutan is a good example to show how a country can prosper from hydropower generation and export. During his trip to Bhutan in June 2014, soon after taking over as Prime Minister of India, he said, “Our Hydropower cooperation with Bhutan is a classic example of win-win cooperation and a model for the entire region.”
However, this hydropower import by India from Bhutan is not a new development. Central Electricity Authority under Union Ministry of Power provides[1], in its monthly reports, power import from Bhutan, these figures are available since 2005-06.
CEA also provides regular status of updates of hydropower projects in Bhutan, the latest one is dated Feb 28, 2015[2], however, the CEA list only includes those projects in which India has provided funding or other cooperation. The Detailed Project Reports of the projects for which India provides funding to Bhutan are approved by the CEA from Techno-economic perspective. There is a separate mechanism called Joint Group of Experts to deal with Indo Bhutan flood related issues, this comes under Union Ministry of Water Resources[3].

India has been importing substantial amount of power from Bhutan for over a decade now, and general impression is that power import from Bhutan has been going up. This is not an entirely correct impression. India imported 5.899 Billion Units (BU, one unit is one kilowatt hour) way back in 2008-09, the import has been lower than that figure every year in the following six years. In the just concluded 2014-15, as the latest figures from the Central Electricity Authority, India imported 4.97 BU, almost 16% lower than the peak import in 2008-09.
Lower power import in winter More significantly, the monthly profile of power import has been undergoing significant changes. For easy understanding, I have divided the year into two parts: the seven month period from April to Oct and five month period from November to March. Since hydropower generation depends on water flow, and since water flow in rivers changes with season, the power generation is expected to be high during monsoon and also during summer months when snowmelt makes significant contribution to river flow in Himalayan region. So it should not be surprising that the power import from Bhutan during April-Oct period of any financial year is higher compared to power import during Nov-March of the same financial year. Indeed, with the exception of one year (2006-07), the power import during April-Oct seven month period has always been above 82%, and power import during the remaining five months of Nov-March has remained below 18% in all years since 2005-06 since CEA started reporting these figures.

Decreasing share of winter power import However, the % of power import during the give months have been steadily going down, and has come down to 9.95% in 2014-15 & corresponding figure for the seven month period of April-Oct has been steadily going up from 82.88% in 2005-06 to 90.05% in 2014-15. This trend seems to indicate that the electricity consumption in Bhutan has been steadily rising, leading to reduction in power import during lean winter months, since these are the months when power requirements for heating would be high. The power requirement for under construction hydropower projects is another factor in this context.
The odd peak in above bar chart in 2006-07 could be due to the commissioning of the biggest operating hydropower project in Bhutan, namely the 1020 MW Tala Hydropower project in that year.
Where does the imported power go? As per the website of the ERLDC (Eastern Region Load Dispatch Centre: http://erldc.org/), the power is distributed among various Indian states (% of electricity) as given below:
Project | Capacity, MW | W Bengal | Bihar | Jharkhand | Orissa | Sikkim | DVC | Other regions |
Tala | 1020 | 38.25 | 25.5 | 11.46 | 4.25 | 0 | 5.54 | 15 |
Chukha | 336 | 31.85 | 29.63 | 10.74 | 15.19 | 2.22 | 10.37 | 0 |
Kurichu | 60 | 50 | 0 | 0 | 0 | 0 | 50 | 0 |
What about peaking power? One of the justifications put forward for pushing more hydropower projects is that they provide peaking power that thermal power projects cannot provide, since hydropower projects can be shut down or restarted within a very short time, which is not possible with thermal power projects. All the power imports from Bhutan are from hydro sources and India remains deficit in peaking hour power demands. For example, as per the latest available Monthly Power status report from CEA, peak power deficit in India was 7006 MW during April 2014-Feb 2015 period at all India level and 300 MW in Eastern Grid. Hence one would have expected that the hydropower import would provide peaking power. However, a review of daily reports from Eastern Region Load Dispatch Centre shows that the power import is generally providing base load and not peak load. This seems like a loss for both India and Bhutan and reduces the justification for more large hydro projects in the region as far as peaking power provision is concerned.

Further Information sources:
- Druk Green Power Corporation, Govt of Bhutan: http://www.drukgreen.bt/
- Bhutan Power Corporation Ltd: http://www.bpc.bt/
- National Load Dispatch Centre, Bhutan: http://nldc.bpc.bt/
- Bhutan Electricity Authority: http://www.bea.gov.bt/
- Bhutan’s National Newspaper: http://www.kuenselonline.com/
- International Rivers has recently put up a blog on status of hydropower projects in Bhutan[4].
- SANDRP blog on fish ladder at Kurichu HEP in Bhutan: https://sandrp.wordpress.com/2014/02/02/fish-ladder-at-kurichhu-hydropower-project-bhutan-some-thoughts/
- SANDRP blog on Water Wheels and hydropower projects in Bhutan: https://sandrp.wordpress.com/2014/07/08/flow-for-worship-flow-for-money-water-wheels-and-hydropower-in-bhutan/
- A blog on Cumulative Impact Assessment of Tawang Basin HEPs in Arunachal Pradesh in India that mentions possible but unassessed impacts in Bhutan: https://sandrp.wordpress.com/2015/04/10/cumulative-impact-assessment-of-tawang-basin-highlights-from-the-nehu-study/
Himanshu Thakkar, SANDRP (ht.sandrp@gmail.com)
END NOTES:
[1] http://cea.nic.in/monthly_gen.html
[2] http://www.cea.nic.in/reports/hydro/bhutan.pdf
[3] http://wrmin.nic.in/forms/list.aspx?lid=350
[4] For an update on status of various hydropower projects in Bhutan, see: http://www.internationalrivers.org/resources/8703.