Geothermal Energy in India

Geothermal Energy in India

Context

Geothermal energy is emerging as a critical, weather-independent renewable energy source in India. With the notification of the National Policy on Geothermal Energy in September 2025 and the commissioning of India's first two deep geothermal wells at Puga, Ladakh, in July 2026, India is transitioning from conceptual R&D to active demonstration-scale power generation.

Core Principles & Working Mechanism

• Origin & Physics: Residual heat from Earth's formation combined with natural radioactive decay -238 (²³⁸U), thorium-232 (²³²Th), and potassium-40 (⁴⁰K),  drives mantle convection. Hydrothermal systems trap superheated water/steam in permeable rock formations beneath impermeable cap rock.
• Baseload Energy: Operates at 80%–90%+ Capacity Utilization Factors (CUF), offering round-the-clock grid stability without depending on solar radiation or wind conditions.
• Byproduct Mineral Extraction: Geothermal brines contain critical minerals like lithium, silica, zinc, and manganese, allowing potential integration with domestic battery supply chains.

Geothermal Potential & Key Provinces in India

According to the Geological Survey of India (GSI) Geothermal Atlas, India holds an estimated ~10.6 GW (10,600 MW) theoretical potential across 381 mapped hot spring locations.

Major Projects & Government Initiatives

• National Policy on Geothermal Energy (September 2025): Provides an overarching legal and regulatory framework for site exploration, single-window clearances, open-access grid access, and fiscal incentives like custom duty exemptions.
• 1 MW Puga Pilot Demonstration Plant (Ladakh): Executed by the ONGC Energy Centre at an altitude exceeding 14,000 feet. In July 2026, two 1,000 m deep geothermal wells were commissioned, recording temperatures up to 135°C at 400 m.
• Wells to Watts Initiative: Repurposing depleted/abandoned oil and gas wells into geothermal power generators. Includes ONGC’s 450 kW pilot project at the Gandhar field (Gujarat) and R&D collaboration with IIT Madras.
• Hybrid Clean Energy Models: Testing solar-geothermal hybrid power generation in Dholera (Gujarat) to compensate for solar diurnal variation.
• Global Strategic Partnerships: Bilateral MoUs with Iceland, Australia, Saudi Arabia, and the United States for deep-well drilling technology, subsurface modeling, and binary cycle heat exchangers.

Technological Challenges

• High Exploration Risk & Capital Expenditure: Deep sub-surface drilling involves high upfront costs without initial guarantees of flow rate or fluid temperatures.
• Corrosion & Scaling: Dissolved minerals, silica, and gases in geothermal fluids cause equipment scaling and pipe corrosion.
• Extreme Altitude Logistics: Promising sites like Puga face harsh freezing winters, short working windows, and complex high-altitude logistics.

Way Forward

Unlocking India’s 10.6 GW geothermal potential requires de-risking early-stage exploration through national geological mapping, deploying Advanced Geothermal Systems (AGS) for deep low-permeability rock, and integrating direct heat uses (e.g., cold storage, space heating, mineral extraction) alongside power generation.

Conclusion

Geothermal energy represents a critical missing piece in India's clean energy portfolio. By offering clean, weather-independent baseload power, it can significantly ease grid stabilization challenges as variable renewables like solar and wind scale up. With key policy frameworks now in place, successful execution at pilot sites like Puga and Gandhar will be pivotal in proving commercial viability, attracting private investment, and establishing geothermal power as a mainstream contributor to India's net-zero transition.