Geothermal Power in Ladakh | 25 Aug 2022

Why in News?

State-run explorer Oil and Natural Gas Corporation (ONGC) will be participating to generate electricity through Geothermal Energy at Puga, a remote valley located in Ladakh, off the road to Chumar on the de-facto border with China.

What do we need to know about the Puga Project?

• About Puga Valley:
  • Puga Valley is situated in the Changthang Valley in the south-eastern part of Ladakh, about 22 km away from the Salt Lake Valley.
  • It is a region of great significance known for its natural beauty and geothermal activities.
  • Puga is also visited for its hot sulphur spring.
• About Geothermal Project:
  • It will be India’s first geothermal energy project and also the world’s highest at 14,000ft.
  • ONGC has started drilling its first well for the project and encountered high-pressure steam at 100 degrees Celsius with a discharge rate of 100 tonne geothermal energy per hour, considered as a good sign for the project.
• Phases:
  • 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.
  • The third phase would involve commercial development of the geothermal plant.
• Benefits:
  • It will boost Ladakh’s potential to emerge as one of the country’s clean energy bowl by expanding the area’s horizon beyond solar or wind power.
  • The pilot plant provides power and heating needs of the nearby settlements of Tibetan pastoralist refugee settlements at Sumdo and nearby areas.
  • A bigger plant will provide 24X7 supply for the far-flung settlements and the large defence establishment in the eastern sector, reducing their dependence on diesel for running generators.
  • The plant can also play a vital role as a stabiliser for the 15-gigawatt solar/wind project being planned in the nearby Morey plains in the southwest.
• Status of Geothermal Energy:
  • National:
    • Geological Survey of India has identified about 340 geothermal hot springs in the country. Most of them are in the low surface temperature range from 370C to 900C, which is suitable for direct heat applications.
      • The potential for power generation at these sites is about 10,000 MW.
    • The hot springs in the country are grouped into seven geothermal provinces:
      • Himalayan, Sahara Valley, Cambay Basin, San-Narmada –Topi lineament belt, West Coast, Godavari Basin and Mahanadi Basin.
    • Some of the prominent places where a power plant can be established based on geothermal energy are:
      • Manikaran in Himachal Pradesh
      • Jalgaon in Maharashtra
      • Tapovan in Uttarakhand
      • Bakreshwar in West Bengal
      • Tuwa in Gujarat
  • Global:
    • Gigawatt-Size Geothermal Capacities:
      • The US:
        • The US leads the world in the amount of geothermal electricity generation.
      • Indonesia:
        • Indonesia was the second-largest geothermal electricity producer.
      • Philippines
      • Turkey
      • New Zealand
    • Mexico and Italy have 900 megawatt-plus capacity, while Kenya has over 800 mw, followed by Iceland, Japan and others.

What is Geothermal Energy?

• About:
  • Geothermal energy is the heat from the earth. This heat is used for bathing, to heat buildings, and to generate electricity.
  • The word geothermal comes from the Greek words geo (earth) and therme (heat), and geothermal energy is a renewable energy source because heat is continuously produced inside the earth.
• Sources:
  • Hot water or steam reservoirs deep in the earth are accessed by drilling.
  • Geothermal reservoirs located near the earth's surface, mostly located in the western U.S., Alaska, and Hawaii.
  • The shallow ground near the Earth's surface that maintains a relatively constant temperature of 50-60°F.
• Uses:
  • Hot water and steam from reservoirs can be used to drive generators and produce electricity for consumers.
  • Other applications apply the heat produced from geothermal directly to various uses in buildings, roads, agriculture, and industrial plants.
  • The heat can also be used directly from the ground to provide heating and cooling in homes and other buildings.
• Benefits:
  • Renewable Source:
    • Through proper reservoir management, the rate of energy extraction can be balanced with a reservoir's natural heat recharge rate.
  • Continuous Supply:
    • Geothermal power plants produce electricity consistently, running 24 hours per day/7 days per week, regardless of weather conditions.
  • Reduced Import Dependency:
    • Geothermal resources can be harnessed for power production without importing fuel.
  • Small Footprint:
    • Geothermal power plants are compact and use less land per GWh (404 m2) than coal (3642 m2) wind (1335 m2) or solar PV with center station (3237 m2). *
  • Clean Energy:
    • Modern closed-loop geothermal power plants emit no greenhouse gasses; life cycle GHG emissions (50 g CO2 eq/kWhe) are four times less than solar PV, and six to 20 times lower than natural gas.
    • Geothermal power plants consume less water on average over the lifetime energy output than the most conventional generation technologies.
• Disadvantage:
  • If harnessed incorrectly, it can sometimes produce pollutants.
  • Improper drilling into the earth can release hazardous minerals and gases deep inside the earth.

Source: TOI