Category: Environment

HOT SPRINGS OF THE HIMALAYAS – Inexhaustible Source of Geo Thermal Energy – Still Largely Untapped

The hot springs of the Himalaya are located in the zones of deep faults that define tectonic boundaries between the Himalayan province and mainland Asia ( Indus – Tsangpo Suture, I-TS), between the Great Himalaya and Lesser Himalaya ( Main Central Thrust, MCT) and in between the Siwalik domain and the Lesser Himalaya (Main Boundary Thrust, MBT). The geo thermal activity is highest in the Ladakh region where heat flow is of the order of 300 mW/m². Heat flow in the hot springs along the MCT have an average rate of  130 ± 30 mW/m² whereas the average rate of heat flow in the MBT region is of of  41 ± 10 mW/m² .

Clearly the Indus-Tsangpo Suture has the greatest potential in the Himalayan region. One such “hot-spot” of the ITS region is the Puga hot spring area located in Ladakh. It covers an area of 15 km2 and this single spot has the potential of 5000 MWh of energy.

Jonathan Craig, honorary professor at University College, London, and the University of Jammu, published a paper in May, 2013 on this subject. According to him “A 20 megawatt geothermal plant at Puga could save three million litres of diesel burnt annually in the region at a cost of approximately US$ 2 million,”  “Such a plant” he adds “would eliminate the need for traditional kerosene stoves and gas-operated heaters during winter and prevent the emission of some 28,000 tonnes of carbon dioxide.”

This inexhaustible source of geo thermal energy is capable of producing hundreds of gigawatts of clean energy.  since 1976, China has been operating a 25 megawatt plant in Yangbaijan, Tibet. Till 2014, the world had  11.13 gigawatts of geo thermal plant installed in 24 countries with the US leading with 3.15 gigawatts. Third world countries are not far behind. The Philippines and Indonesia hold the second and third place respectively producing 1.9 and 1.3 gigawatts of geo thermal energy.

Geo Moore, a geologist at the Energy and Geosciences Institute, University of Utah, told a conference on sustainable resource development held in the June, 2014 in Leh , “I hope lessons from elsewhere in the world can help harness these resources in the Himalayas,”

Sources:

Dynamic Himalaya by K S Valdiya
https://www.sciencedirect.com/science/article/pii/S0012825213000949
http://www.earthscienceindia.info/pdfupload/tech_pdf-1255.pdf
https://www.thethirdpole.net/en/2014/07/31/himalayan-geothermal-potential-untapped/
https://www.scidev.net/south-asia/environment/news/himalayan-geothermal-potential-untapped.html

Himalayas, the 2400 Km long and 250-300 Km wide mountain barrier separates the Indian subcontinent from the mainland Asia. This insuperable barrier stops the cloud from going North and is responsible for the peculiar Monsoon cycle of the subcontinent. However, in today’s discussion we are not going to take that into account and see how the water stored in the lakes, rivers and glaciers of the Himalayas directly effect the lives of the people of the subcontinent. Stay with me. Next we’ll see if at all we this magnificent giant deserves the title of the “Water reservoir of the Indian Subcontinent” or not.

Nearly 60% of India’s population lives in the densely populated Indo – Gangetic plains. Approx 1,20.00,000 million cubic meters of water flows down the Himalayan rivers annually and nourishes the millions living in the plains.  Believe it or not this huge amount of flowing water has tremendous power potential. Nearly 2,46,600 million cubic meter from these river can be utilised in irrigation process. In table 1.1 we’ll see the potentials of three major Himalayan river systems supplying the juice of life into the subcontinent.

Irrigation & Power potential of the rivers

River System	Flow (in 109 m3 / year)	Irrigation Potential (in 109 m3)	Power Potential (kW at 60% Load factor)
Brahmaputra	479.3	12.3	9988
Ganges	459.84	185.0	11579
Indus	207.8	49.0	6582
Total	1146.94	246.6	28149

 

This almost inexhaustible source of fresh water gets replenished every year by direct rainfall & the melting of snow and ice which occurs in the higher altitude. The average rainfall in the whole Himalaya is ~289 cm (https://en.climate-data.org/south-america/ecuador/provincia-de-orellana/himalaya-179049/), though it varies from one region to other within Himalayas.

The average rainfall is ~240 cm/yr in the southern front, ~150 cm/yr in the most populated belt of the Himalaya (1500  – 2500 m) i.e. in the Lesser Himalaya region. The Himalayan domain ( 5000- 8000 m) experiences a surprisingly high but unpredictable rainfall pattern ranging from 240 cm to 350 cm annually where as the arid Tethys domain across the Great Himalaya in the North  faces very little rainfall (10-15 cm/yr).

The major portion of the rain water flows down the valleys in the short duration of monsoon (more or less three months) and only a small part (less than 15%) percolates down through the soil and rocks to rejuvenate the mountain springs  which essentially feed the major Himalayan rivers systems.

Although major chunk of fresh water reserve, is locked in the 1400 Km³ of snow and ice, spread over 33,050 Km²  of area (Dyurgerov and Meier, 2005).  This is in higher altitudes above the snowline, which varies from 4300 to 5800 m depending on latitude and other factors). More than 15000 glaciers of various size contribute to this.

All these statistics may not be meaningful. Let me present it another way to put things into perspective.

The Ganges-Brahmaputra-Meghna basin itself is home to more than 700 million people, which is twice the population of the United States. It relies solely on this river system for daily need of fresh water (global-greenhouse-warming.com/himalayan-gangotri-glacier.html). If we take into account the water flowing down from the whole Hindukush – Karakoram- Himalaya (HKH) range, number increase. Estimated 1.9 billion people rely on this for drinking, agriculture, energy and other purposes. Simply meaning,  more than two out of every ten living human being of the world is dependent on the water stored in the Himalayas in one way or the another.

Now you tell me if there’s any exaggeration when I name this mighty giant as the water reservoir of the subcontinent?

To our utmost regret,  this great treasure is under formidable threat. Recent study shows that one third of the Himalayan glaciers will melt by the end of this century . If precautionary measures are not taken Himalaya might lose two third of its present glacier caps. This is a discussion for another day and will take me at least another blog to give you the briefest idea about what is happening.