 |
| Fig-1: Principle of Hydroelectric Power Generation |
What salient feature is required for seamless hydroelectric power generation that Bhutan encompasses?
Hydroelectric power generation is
the topper power generation system considering the environment-friendly green energy generation. Hydroelectric generation is also one of the cheapest electrical
energy production methods.
The limitation of hydroelectric energy
generation mostly depends on the natural geographical location that Bhutan can
meet naturally. Topographic facilities to generate hydroelectric energy may
change Bhutan’s economical position, just exporting the surplus electricity
to neighbours’ countries like India, Bangladesh etc.
Bhutan’s river system, means huge
water resources are mainly in the form of rivers. There are a few lakes, but
they are mostly small and are mainly located in the remote high altitude alpine
areas and are not much of economic utility. Some of these lakes are glacial
lakes and outbursts of these lakes from time to time have resulted in enormous
flash floods and damage to lives and property.
As per the topography of the
country, the major rivers flow north to south with their sources in perpetual
snow cover and flowing right down to the tropical zone on the border with
India.
While most of them originate in
Bhutan itself, a few of them have originated in China. These rivers have steep
longitudinal gradients and narrow steep gorges, which occasionally open up and
provide broader valleys with small areas of flat land for cultivation.
Some of the main rivers have cut
1000 m deep valleys through the mountains. The majority of the valleys are
narrow V-shaped valleys indicating that water erosion has been the main cause
of their formation.
Due to the steep longitudinal
gradient and the high annual runoff, these rivers provide significant
hydropower potential with an estimated theoretical potential of 30,000 MW.
Due to the existence of distinct
rainy and dry seasons, there are large seasonal variations in the river flows.
These rivers carry large volumes of flow and often also sediment during the
monsoon season, whereas the flow is relatively low during the dry season due to
the limited rainfall and the limited existence of major groundwater reservoirs.
Snow-melt from the high altitude
alpine areas in the north contributes to the flow at the end of the dry season.
Apart from the major north-south
flowing rivers, Bhutan conferential and rain-fed tributaries that flow do often
as waterfalls to join the main rivers.
Sponsored:
What
makes Bhutan a unique hydroelectric energy potential country?
Bhutan’s water resources are
confined to four major river basins which originate from the high altitude
alpine area and from the perpetual snow cover in the north and flow into the
Brahmaputra River in the Indian plains.
BASIN-I (Comprises of
Amochhu and Wangchhu Basin): It is the smallest of the river systems also known
as Torsachhu. It has its origin in the Chumbi valley of Tibet and flows through the western districts of Haa and Samtse before draining into the plains of India. It
consists of three major tributaries from the three valleys of Thimphu, Paro and
Haa. They originate within Bhutan from the glaciers and snow-capped mountains
in the north. It flows through Chukha District to the Indian plains of West
Bengal.
BASIN-II (Punatsangchhu
Basin): Also known as Sankosh Chhu, consists of two major tributaries Phochhu
and Mochhu that originate from the Gasa district. The two rivers join at Punakha
Dzong to become Punatsangchhu (Sankosh) that flows through Wangdue Phodrang,
Tsirang and Sarpang Districts before reaching the Indian plains.
BASIN-III (Manas Basin):
It is the biggest river basin and drains almost all the catchments of Central and Eastern Bhutan. It consists of four major sub-basins:
Mangdechhu
- originating close to Gangkhar Punsum (Among Bhutan’s highest peaks at 7239m);
Chamkharchhu - originating close to Gangkhar Punsum;
Kurichhu -
originates in China;
Drangmechhu
- originates from the north-eastern part of Trashiyangtse, Arunachal Pradesh in
India and China.
Bhutan has three regions
distinctly different due to prominent north-south mountain ranges that separate
each area resulting in different topographical features:
Western Bhutan: Comprising
of Haa valley, Paro valley, Thimphu, Punakha valley, Wangdue Phodrang and high
passes or La’s: Cheli La, Dochu La & Pele La which separates Western Bhutan
from Central Bhutan;
Central Bhutan: the Black
Mountains separate Western Bhutan from Central Bhutan. This region includes
Trongsa and rich valleys of Bumthang, including Chumey;
Eastern Bhutan: This
region comprises Mongar, Lhuentse, Trashigang and Trashiyangtse. Senior
valley separates Central from Eastern Bhutan. The altitude here is much lower
than in the other regions.
What is the Exceptional
Hydroelectric friendly geo-location of Bhutan?
 |
| Fig-2: A Perfect Water Reserve Dam for a Hydroelectric Power Plant |
The Himalayan Kingdom of Bhutan,
by virtue of its geographical location on the southern slope of the Eastern
Himalayas, is blessed by nature with attitudinal varying landmass with good
vegetation cover, the perennial flow of water in the swift-flowing rivers and fair
climatic conditions.
Bhutan is a land-locked country
bordering China in the North and India in the West, South and East. Bhutan lies
between latitudes 26.7°N and 28.4°N and longitudes 88.7°E and 92.2°E. It covers
an area of 38,394 square kilometres roughly measuring 140 km north to the South
and 275 km East to West.
It is estimated that over 72% of the land is
under the vegetative cover with altitude varying from 100 m above mean sea
level (msl) in the southern sub-tropical region to 7550 msl in the Northern
Alpine region. Bhutan receives a fair amount of annual rainfall varying from 500
mm in the North to 5000 mm in the South.
Thus, Bhutan is endowed with rich
potential for harnessing hydro-power. Most of the schemes identified are
run-of-the-river types and they are found to be techno-economically sound with
least-cost and environment-friendly. Few reservoir schemes are also identified
with limited and/or no environmental impact in the Southern belt before the
Bhutanese rivers fan out and enter the Indian plains.
Bhutan has an estimated hydro
potential of 30,000 MW and 120 TWh mean annual energy generation indicating an
average development potential of 781 kW in a square kilometre of land area.
So far 23,760 MW has been
identified and assessed to be technically feasible. Only about 5 % of the
potential is harnessed so far. The electricity sector’s share of the GDP has risen
to about 20% and is the single largest contributor to the economy.
The development of several more
mega hydropower projects over the current and future plan periods is likely to
see an even greater prominence of the electricity sector within the national
economy.
Bhutan’s ability to harness the
hydro-power resources has been made possible because of the close and friendly
ties with its neighbour, India. India has been the leading partner in providing
both technical and financial assistance towards developing the vast hydro-power potential
of Bhutan.
The relationship developed in the
Hydropower sector has been a win-win situation for both countries as India
has a power shortage while Bhutan has a large hydropower potential. Hydroelectricity export has become the single
most important source of revenue for Bhutan.
The Bhutanese economy saw estimated GDP growth of 8.5% in 2006-2007, an increase from 7.1% in 2005-2006.
According to the annual report published by Royal Monetary Authority (RMA) the
increase in GDP was driven by the commissioning of the Tala Hydro-Electric Project
(1020 MW). Moreover, the growth is largely spurred by the sale of electricity
to India from the power projects. The sale of Electricity constitutes about 80% of
the total exports of Bhutan.
Sponsored:
What
is the hydroelectric power generation status of Bhutan?
The tenth and Eleventh
Five Year Plans for hydroelectric generating plants which are implementing by the Kingdom of Bhutan is listed in the table given below:
Sl. No.
|
Project Name
|
Installed Capacity in MW
|
Construction Perion
|
01
|
Punatsangchu
I HEP
|
1200
|
2008-2015
|
02
|
Mangdechu
HEP
|
720
|
2009-2016
|
03
|
Punatsangchu-II
HEP
|
1000
|
2009-2016
|
04
|
Bunakha
Reservoir
|
180
|
2010-2016
|
05
|
Wangchu
HEP
|
900
|
2010-2017
|
06
|
Chamkarchu-I
HEP
|
670
|
2011-2017
|
07
|
KholongchuHEP
|
600
|
2012-2018
|
08
|
Amochu
Reservoir
|
620
|
2012-2018
|
09
|
Kuri-Gongri
HEP
|
1800
|
2012-2019
|
10
|
Sunkosh
Reservoir
|
4000
|
20111-2020
|
|
Total
|
11690
|
2008-2020
|
Hydro Power is the backbone of
the Bhutanese economy. The rugged terrain, compounded by the fact that the
Country is landlocked does not provide much economic advantage to Bhutan.
Transportation costs are high and
unless Bhutan can think of certain niche products, her exports are not going to
be competitive. The decision by the Royal Government to exploit its water resources
for the production of electricity has changed the economic scenario for Bhutan. The
rapid attitudinal variations with swift-flowing rivers have made Bhutan the
natural haven for hydropower production.
The close and friendly ties
between Bhutan and India have provided the necessary political will and the
market for Bhutan’s power, as India has a huge power deficit. While electricity
has provided the much-needed revenue, the Royal Government has also prioritized
network expansion in the Country.
It is expected that by 2020, the entire
country will have access to electricity. Industrial activities are on the increase
with the commissioning of the Tala Hydroelectric Project (1020 MW) in the year 2006.
There is, however, a need to ensure that internal electricity tariff is kept
affordable, so that, it becomes the main source of energy in the country and
also to stimulate industrial activities.
Water is a natural resource that
is in great abundance in Bhutan and the mountainous topography and climatic
characteristics have endowed the country with a vast hydro-power potential of
around 30,000 MW. Of this 23,760 MW is technically feasible which translates
into a mean annual energy production capability of around 120,000 GWh.
This tremendous comparative advantage
for the country has been tapped effectively through a mutually beneficial and
highly successful partnership with the Government of India resulting in a
win-win situation for both countries. India has generously provided valuable financial and technical resources to undertake the implementation of these complex and mega projects in addition to
assuring the purchase of any surplus power generated.
The availability of reliable
electricity also serves India’s growing needs for cheap power to continue
growing rapidly and ensure its energy security. For Bhutan, the effective and
sustainable utilization of its water resources has proved to be the key
strategic success factor in furthering its sustainable development goals.
The harnessing of the country’s
hydro-power potential closely parallels the rapid pace of socio-economic development
and progress in Bhutan and has largely underpinned the strong economic growth
and generated valuable resources to pay for a significant part of its social
and other development investments.
At the start of the new
millennium in 2000, hydro-power generation capacity in Bhutan stood at around
353.65 MW. By 2007 it had quadrupled to 1,489 MW. This capacity is further
expected to be increased to 1,602 MW by the end of Bhutan’s Tenth Five Year
Plan (2007-2012) and possibly reach 10,000 MW by 2020. The expansion of
hydropower production capacity has had an enormous impact as by the end of the
Ninth Five Year Plan, the energy sector contributed to around a quarter of GDP
and 60% of national revenues.
This also excludes the major
contribution that hydro-power infrastructure development makes to the
construction sector, which accounts for another quarter of GDP. With a further
doubling of capacity envisaged by the end of the 11 the Five Year Plan in 2017
or by the year 2020, the energy sector will probably contribute close to half
of GDP and account for around three-fourths of the total national revenues.
The energy sector is thus
strongly poised to continue leading and boosting growth in the future economic
scenario and will greatly enhance the prospects of promoting higher living
standards and reducing poverty levels in the country.
These projections are
realistically based on and anchored by the Indo-Bhutan agreement on the long
term cooperation in the field of hydro-power development signed by the two
governments in July 2006. Under this umbrella agreement that is valid for sixty
years, India will import a minimum of 5,000 MW of electricity from Bhutan by
2020.
Taking into consideration
domestic consumption, the country needs to develop a hydro-power capacity of
around 10,000 MW which would require the capacity addition of another 8,500 MW.
With this capacity addition, it is envisaged that the country will have tapped around
42% of its technically feasible hydropower resources by 2020.
Just using the natural facilities
hydroelectric power generation seamless geo-support that may make the Himalayan
Kingdom of Bhutan a giant green electricity exporter of the Asian continent.
