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Image credit- @Roli Chauhan
The enchantingly beautiful land of Ladakh has been bestowed with the endless beauty of nature in form of pristine lakes, gurgling rivers, beautiful mountain passes, an abundance of sunlight, and what not.
It is situated in the Trans-Himalayan region and sits at the mouth of the Tibet region, which is also called the Third pole as it stores volumes of glacial ice.
But the unfortunate rise in the global temperatures due to climate change has led to the melting of glaciers at an unprecedented rate (according to Shakeel Romshoo, corresponding author of the study of Jammu and Kashmir and Ladakh glaciers, published in the journal Scientific Report) and increasing incidents of rainfall in the cold desert of Ladakh.
Also, Ladakh’s economy is majorly dependent on tourism as it contributes around 50% of the local GDP. This leads to an increase in vehicular pollution, increase in carbon emissions, etc, and puts pressure on the fragile mountain ecosystem of Ladakh.
This has invoked an urgent need to adopt sustainable means of development to mitigate the threatening effects of climate change. Leading in this direction, Prime Minister Narendra Modi also envisioned and pressed on the idea of Carbon Neutral Ladakh. Its focus is to minimize carbon emissions in not only every developmental activity but in day-to-day life as well.
According to India’s Third Biennial Update Report to the UNFCCC (United Nations Framework Convention on Climate Change) Carbon neutrality for Ladakh is not a mitigation goal but a development vision.
According to UNEP’s (United Nations Environment Programme), Emission Gap Report 2022, India is third among the top Seven Emitters in the world following China and EU27.
Being the fastest-growing economy, the major chunk of energy-based requirements comes from fossil fuels (coal, petroleum, and diesel) which are the major contributors to carbon emissions.
So now, there is an urgent need to focus on the optimum use of both conventional and non –conventional sources of energy, with a gradually shifting towards non-conventional resources, like solar power, wind energy, hydropower, and the latest geothermal energy.
In the recently held COP-27 (Conference of Parties-27), at Sharm-al-Sheikh, Egypt, Indian Environment Minister Shri. Bhupendra Yadav said that the Long Term Net Zero Strategy at COP-27 is based on two themes “Climate Justice” and “Sustainable Lifestyle”. India’s LT-LEDS (Long Term Low Emission Development Strategy) at COP 27 rests on seven key transitions to low-carbon development pathways. One of them is the low-carbon development of electricity systems. In order to achieve this Indian government is keen to focus on the expansion of renewable and strengthening of the grid.
India is endowed with an abundance of non-conventional energy resources, making it a perfect candidate in harnessing and utilizing the benefits of Renewable Energy and meeting its Sustainable Development Goals (SDGs- set up in 2015 by the United Nations General assembly and adopted by all UN members)
A not-so-new but less explored and exploited, an entrant in the area of non-conventional energy sources is GE- Geothermal Energy.
Geothermal Energy is heat that is generated deep within the Earth’s core. It is a clean, green and renewable source and can be harnessed 24/7 for space heating, power generation, etc. Geothermal Energy is generated nearly 4000 miles below the Earth’s surface (Prajapati, Shah, and Soni, 2022). The Earth’s double-layered core comprises molten rock surrounded by a solid iron core. Radioactive elements in the rocks inside the Earth are continuously degrading (Puppala and Jha). Therefore a very high temperature is continuously generated inside the Earth resulting in the creation of Geothermal Energy (Bharadwaj and Tiwari 2008). Volcanoes, erupting geysers, hot springs, etc are various forms of GTE (Geothermal Energy) found on Earth’s surface. These are formed as magma (partly molten rock) heats nearby rocks and underground aquifers. This heat can be captured and used directly for generating heat and steam.
Historically Geothermal Energy has been used for thousands of years across the world. From native Americans recuperating around hot springs to the presence of hot springs spas in Bath, England (town named after the presence of these hot springs used for bathing purposes), Romans building elaborate systems of steam pools using heat from the region’s shallow pockets of low-temperature geothermal energy, this form of energy has been in use since ages.
In India too, the presence of hot springs, and pools all along the Himalayan region, mostly associated with religious purposes and ablutions, speaks of its knowledge and use since time immemorial.
However, in present times, the detrimental effects of climate change have accelerated the search and use of such ancient, environmental-friendly sources of renewable energy.
India is also increasing its Renewable Energy potential and has proposed to harness 10,000 MW (10GW) of GTE by 2030 through active international collaboration with USA, Mexico, Iceland, Philippines etc.
In India, there are 340 Geothermal Hot springs and 7 Geothermal Provinces, as identified by the GSI (Geological Survey Of India). Most of these are in the low surface temperature range from 370 º Celsius- 900 º Celsius, suitable for direct heat application. Also, most of the geothermal systems in India are in the low–enthalpy geothermal system category. Therefore it is suggested that these areas can be effectively used for power generation using a binary cycle technique known as Organic Rankine Cycle (ORC) (Sustainable Renewable Energy Report, 2016). A Geothermal power plant is essentially a hydrothermal convection system that captures Earth’s heat energy in the form of steam coming out of the drilled wells and converts into electricity through motors. Wells are drilled at geothermal hotspots to circulate water through reservoirs of high heat capacity.
Ladakh, India’s newest UT (created on 31st October 2019) has emerged as the most promising region in the generation of Geothermal Energy. Ladakh’s location is at the confluence of two continental plates (Indian and Eurasian plates) and the availability of rivers and other water sources makes it a promising region for geothermal energy generation.
Puga valley and Chumathang area (40 km North of Puga) in Ladakh were earlier explored in the 1970s-80’s by GSI (Geological Survey of India). During this period, wells of 284 metre of depth were bored and GSI found a temperature of 260 º Celsius at this depth. However, much progress was not made owing to the lack of focus on renewable energy. With the passing of decades and surfacing issues of global warming, priority to utilize renewable energy has tilted the focus once again on this region
Envisaging such clean and green fuel to achieve carbon neutrality in Ladakh, the use of Geothermal is being projected on various developmental platforms.
In this direction, an MoU was signed in February 2022, between the UT administration of Ladakh and state-owned ONGC (Oil and Natural Gas Corporation), thus establishing the first-ever Geothermal field development project in India at Puga valley in Ladakh. In the first phase, the company will drill 1,000-metre-deep wells to run a one-megawatt power plant as a pilot. The second phase envisages a deeper exploration of the geothermal reservoir and a higher-capacity demonstration plant. A commercial size plant will be set up in the third phase.
The Puga hot springs area, located at the junction of the Indian and Tibetan plates along the Indus suture zone has the greatest potential for GTE development. This area exhibits vigorous geothermal activity in form of hot springs, mud pools, sulfur, and borax deposits. It is estimated that more than 5000 megawatt of GTE is available at Puga.
According to Mr. Udai Shankar, ONGC’s project manager at the Puga GTE power generation site, the 5 km stretch of Puga nullah is between Sumdo village and Puga School, the origin of the nullah being near the school. The round-the-year temperature of this nullah is 9 º Celsius (despite the outside temperature in the negatives) and it never freezes. Down the stream water goes down and enters some land formation and comes out at a point where its temperature reaches 26 º Celsius, making it a charging point. Water samples of a place, 18 km from Puga, at 18000 ft height were compared with the water of Puga nullah, by GSI, and the chemical content and the chemical content and nature of both the samples were found to be almost similar in nature. So it was concluded that the source of water was most probably at that height only. This type of study is essential to measure the viability and life of the GTE source.
Shankar states that” Any temperature above 225 º Celsius is considered as grade 1 reservoir and very good quality steam can be extracted from it. This ensures smooth turbine functioning and more than 50% power generation. The residual heat produced can be utilized for other purposes like space heating, aqua farming, greenhouse vegetable farming etc”.
He also suggests that the Chumathang region being closer to Leh than Puga valley, power generated through geothermal can be easily brought through insulated pipes and the energy loss will be a maximum of up to 10 percent, thus increasing the efficiency.
Ladakh is a cold desert and experiences extreme cold and harsh climatic conditions for more than eight months, forcing the common people to adopt mostly conventional methods of generating heat for domestic needs. The extensive use of conventional kerosene/wood-based Bukhari for space heating produces a lot of carbon emissions, making it an unsustainable source of heat generation.
During winters when the temperature dips to minus 30, a need for direct thermal space conditioning is there instead of converting thermal energy into electrical energy (Gupta and Pal, CPWD Engineers). Freezing temperatures minimize the role of hydropower for energy needs. Solar power though abundant in nature has its limitations of presence only in the day time, higher cost of installation, and transmission loss, making it a viable but limited source of renewable energy.
Here comes the role of Geothermal Energy which is present around the clock with nil requirements of fuel to generate heat energy.
Geothermal Energy can be used for both space heating and space cooling. Unlike power generation through Geothermal which is site-specific, space heating and cooling can be done anywhere.
Space heating relies on the difference between the outside air temperature and the temperature of ground and water on the earth. Generally, beyond 50 meters of depth, the temperature of the earth is found to be stable with a normal range of 14 º Celsius – 16 º Celsius.
In space heating, a geothermal heat pump is installed around 10 feet underground. These pipes are filled with water or an antifreeze solution. The water is pumped around the closed loop of pipes. These ground source heat pump systems help to cool buildings in summer and maintain warmth in winter. This occurs by absorbing the earth’s heat as the water circulates back into the building.
Shankar says that the 60-80º Celsius temperature range is sufficient for space heating. Water is not consumed in this system as only heat is utilized and water is discharged back to the source, thus making it ecologically viable. The last drop of energy can be utilized in Ladakh due to favourable environmental conditions.
Geothermal is a clean, green, and continuous source of energy present 24/7,365 days. It requires minimal land for its generation, does not require any storage, and is independent of changing weather, day–night variation, and seasonal conditions. Thus for a place like Ladakh which has undulating terrain, the cost of Geothermal Energy generation is minimized. Since it does not pollute the environment or produce any bi-product, its large-scale harnessing will not pose any ecological or environmental threat to Ladakh.
It is estimated that a Geothermal power plant having a power generation capacity of 1 megawatt can reduce 6000 metric tonnes of CO2 emissions per year (Sanyal and Butler).
However harvesting geothermal energy still poses some challenges. The process of injecting high streams of water into the earth can result in minor earthquakes. Besides this, geothermal plants can release
small amounts of greenhouse gases, such as hydrogen sulfide and carbon dioxide from the earth’s surface. Water flowing underground sometimes picks up small traces of toxic elements like arsenic, and mercury which could pollute the water stream.
The initial cost of installation of a geothermal plant is higher. The dearth of ample skilled manpower and required R&D in this field is still in a nascent stage in developing countries like India.
However, with shared knowledge and assistance from countries that have already pioneered in this field, such as Iceland, it could prove a win-win situation for the world at large.
(Disclaimer: The views and opinions expressed within this article are the personal opinions of the author. The facts, analysis, assumptions, and perspectives appearing in the article do not reflect the views of Republic TV/ Republic World/ ARG Outlier Media Pvt. Ltd.)