Geothermal Energy

1. At a Glance

• Geothermal energy is heat from the Earth's interior. It is a constant, low-carbon source that does not depend on weather. It can generate power or be used directly as heat [1].
• Unlike solar and wind, it is available round the clock. That makes it a possible baseload renewable for India's Net Zero 2070 target [1][2].
• Why it matters for UPSC: it brings together static geography (Earth's interior, mantle convection, hot springs), energy policy (National Policy on Geothermal Energy, 2025) and current affairs (Puga Valley wells, 2026) [1][2].

2. Why in the News

• September 2025: The Government of India notified the National Policy on Geothermal Energy. MNRE is the nodal ministry [1][2].
• July 2026: The ONGC Energy Centre commissioned India's first two geothermal wells at Puga Valley, Ladakh. They will lead to India's first 1 MW demonstration geothermal power project [1].

3. Background & Evolution

• Source of the heat: radioactive decay of uranium, thorium and potassium, plus heat left over from the planet's formation [1].
• Survey base: The Geological Survey of India (GSI) mapped 381 hot springs and identified 10 geothermal provinces [1]. Other PIB material says GSI explored 381 areas, with an estimated potential of 10,600 MW [3].
• Milestones in order:
• SCCL commissioned a 20 kW pilot geothermal power plant at Manuguru, Bhadradri Kothagudem district, Telangana. The Ministry of Coal funded it with ₹2.42 crore. It uses closed-loop Binary Organic Rankine Cycle technology [4].
• 15 September 2025: National Policy on Geothermal Energy notified [2][3].
• An R&D project at IIT Madras was sanctioned to explore geothermal energy in abandoned oil wells [3].
• A pilot at Ankleshwar tests the reuse of abandoned oil and gas wells [1].

• July 2026: two Puga wells commissioned, each 1,000 m deep, at over 14,000 ft [1].

• Related earlier initiative: MNRE's Renewable Energy Research and Technology Development Programme (RE-RTD) develops indigenous, low-cost renewable technologies, including geothermal [1].

4. Core Static Facts

5. Multi-Dimensional Analysis

Economic

• It supplies baseload renewable power around the clock, which eases the grid-balancing cost that solar and wind create through their intermittency [1].
• Reusing abandoned oil and gas wells uses drilling skills, well data and infrastructure that already exist. This can cut upfront exploration and drilling cost [1][2].
• Commercial-scale power generation has not yet been established in India. The sector is still at the demonstration stage [1].

Environmental

• It is low-carbon, and reinjection helps keep the reservoir sustainable [1].
• Direct uses such as GSHPs and district heating can replace fossil fuels for heating in cold regions like Ladakh [1].

Scientific / Technological

• Power generation works like a conventional thermal plant, except that underground heat replaces burning fuel [1].
• Binary ORC technology makes it possible to use low- and medium-temperature resources (Manuguru) [4].
• EGS creates engineered reservoirs where natural permeability is missing. USGS has published an electric-resource assessment for EGS [5].

Governance / Administrative

• The 2025 policy sets up a regulatory framework for public and private participation. It also supports a national data repository, pilot projects and Centres of Excellence [1].
• It needs coordination across ministries: MNRE for renewables, MoPNG/DGH for wells, and the Ministry of Coal for CPSE pilots [2][4].

Geopolitical / Strategic

• MNRE has expanded international collaboration to bring in geothermal know-how [3].
• Puga sits in a strategically important high-altitude border UT. Local energy there reduces dependence on long supply chains [1].

6. Recent Developments (last 12–18 months)

• 15 Sep 2025: National Policy on Geothermal Energy notified, aligned to Net Zero 2070 [2][3].
• 2025: MNRE expanded global collaboration on geothermal energy [3].
• 2025: USGS published a fact sheet on the EGS electric resource [5].
• July 2026: First two geothermal wells commissioned at Puga Valley, Ladakh; a 1 MW demonstration plant is planned [1].
• Ongoing: Ankleshwar pilot on abandoned wells and IIT Madras R&D project [1][3].

7. Prelims Hooks

• India's first geothermal wells: Puga Valley, Ladakh, commissioned by the ONGC Energy Centre in July 2026 [1].
• Puga wells are 1,000 m deep, at more than 14,000 ft altitude [1].
• Puga is meant to lead to India's first 1 MW demonstration geothermal power project [1].
• National Policy on Geothermal Energy notified on 15 September 2025. Nodal ministry: MNRE, not MoPNG [2].
• GSI has mapped 381 hot springs and 10 geothermal provinces [1].
• India's theoretical geothermal potential is about 10.6 GW, spread across 42 promising sites [1].
• Global installed geothermal capacity at end-2025: 15.67 GW [1].
• Ankleshwar pilot: repurposing abandoned oil and gas wells for geothermal use [1].
• 20 kW pilot geothermal plant at Manuguru, Telangana, built by SCCL and funded by the Ministry of Coal [4].
• Manuguru uses closed-loop Binary Organic Rankine Cycle technology [4].
• An IIT Madras R&D project was sanctioned for geothermal energy from abandoned oil wells [3].
• Earth's interior heat comes from radioactive decay of U, Th and K, plus residual heat from planetary formation [1].
• The mantle is the largest layer and is semi-solid. The outer core is liquid [1].
• GSHPs are a direct-use application, not a power-generation one [1].

8. India Has Tried Geothermal Power Before, and It Never Reached the Grid

• Puga was drilled decades before the 2026 'first wells'
• In 1996, the government told the Lok Sabha that exploratory drilling at Puga had found shallow reservoirs (hot water close to the surface) [9].
• The only project then using that heat was for poultry farming and mushroom growing, not electricity [9].

• So the 2026 wells [1] are best read as the first deep wells built for a power project, not the first holes ever drilled at Puga. Note this for any Prelims statement using the word 'first'.

• Tattapani (Chhattisgarh) has had at least two false starts

• In 2001, PIB said NHPC had been given a pilot geothermal power plant at Tattapani. It hoped to start generating power within about one and a half years [7].
• Later, NTPC signed an MoU with CREDA (the Chhattisgarh state renewable energy agency) to explore Tattapani and then build a project there [8].

• India still has no commercial geothermal power [1]. Neither attempt produced a working plant.

• Why this matters for the 2025 policy

• The weak point was never a lack of mapped sites. GSI had listed hot springs long ago [1].
• Projects stopped at the step between 'we know the heat is there' and 'someone pays to drill and build'. The next section explains why that step is so hard.

9. Why Nobody Wants to Pay for the First Wells

• You have to spend crores before you know if the site works
• A typical first round of exploration with 3 to 5 test wells costs US$20–30 million [6].
• Until those wells are drilled and tested, nobody knows how much hot water will flow or how hot it is. The World Bank calls this resource risk [6].

• If the wells come up weak, that money is simply lost.

• Private companies use their own money for this step, so they avoid it

• Exploration drilling is usually paid from owner equity (the company's own money, not a bank loan). Banks will not lend against a resource nobody has proven [6].

• So private firms, especially in developing countries, stay away from new, untested fields [6].

• It takes years before any income arrives

• Exploration and test drilling take about 2–3 years. Building the well field and the plant takes another 3–5 years [6].

• Puga follows this pattern. Wells came in 2026 [1], but it is still only a 1 MW demonstration project [1].

• Rewards for selling power arrive too late to help

• Tools like feed-in tariffs (a guaranteed price for every unit of power sold) only pay once a plant is running [6].
• The World Bank finds that these tools alone usually do not get companies to pay for the risky first drilling [6].

• This is the test for India's 2025 policy. Its pilots, data repository and Centres of Excellence [1] help, but the question to ask is who pays if a well comes up dry.

• The world as a whole has the same gap

• Global potential is estimated at 70–80 GW, but only about 12 GW was in use when the World Bank survey was written [6].

10. What Turkey, Kenya, the Philippines and Japan Did

• Turkey: the geological survey drilled first, and private firms followed
• Turkey's state mining and geological survey agency, MTA, published an inventory of its geothermal waters and drilled the first wells in many fields [6].
• The government also passed a Renewable Energy Law with a guaranteed feed-in tariff. Geothermal power began to grow from 2008 [6].
• The fields MTA had already explored were among the first ones private companies developed, because MTA's work had cut the risk [6].

• India's parallel: GSI has mapped 381 hot springs [1], but mapping is not drilling. Turkey's lesson is that the state body must drill too.

• Kenya: the state took the drilling risk and built power lines

• Kenya set up a state-owned geothermal development company to take on resource risk. It sells steam to IPPs (independent power producers, private firms that generate and sell electricity) [6].

• Kenya also guaranteed the price of power or steam, and ran a coordinated programme to build transmission lines to remote fields [6].

• Philippines: a state oil company started a geothermal arm

• In 1976, the state-owned Philippine National Oil Company (PNOC) created a geothermal subsidiary, EDC, to explore and develop fields [6].
• Capacity grew fast between 1979 and 1983. EDC was later sold to private owners in 2001 [6].

• India's parallel: ONGC Energy Centre is already the agency at Puga [1]. The Philippines shows how an oil company's drilling skill can become a geothermal business.

• Japan: support was withdrawn too early

• Japan's cost-shared drilling (where the government pays part of the drilling bill) drove growth from 1975 to 1995 [6].
• The programme ended in 2002 because geothermal was thought to be mature. No new projects came for almost 20 years, and capacity stayed at 536 MW [6].

• Japan restarted support in 2012 with a feed-in tariff of ¥42/kWh for plants under 15 MW [6].

• Australia: money alone is not enough

• Australia invested about AU$300 million, but it still has very little geothermal power [6].
• Its rocks were deep and had low permeability (water cannot flow easily through them), and the best sites were far from the grid [6].

11. The Case Against Betting on Geothermal, and an Honest Answer

• The strongest objection: too small, too slow and too uncertain
• India's whole theoretical potential is about 10.6 GW [1]. After about 30 years of trying, the country has no commercial plant [1][7].
• Many Indian sites are low or medium temperature. Manuguru needed Binary ORC technology (a closed loop where hot water heats a second liquid that boils at a lower temperature) to produce only 20 kW [4].
• EGS, the technology that could reach beyond natural hotspots, is still described by the World Bank as not proven commercially [10].

• Australia and Chile show that a country can spend heavily and still get little or no power [6].

• What the objection gets right

• Geothermal will not be a large part of India's grid-scale electricity any time soon. Treating 10.6 GW as a target would be a mistake [1].

• Where the objection goes too far

• The case for geothermal does not rest on GW totals. It rests on round-the-clock power and heat in specific places [1].
• In Ladakh, direct uses such as heat pumps and district heating can replace fuel that has to be carried in over long distances [1]. Puga's own early use was heat for farming, not power [9].

• Abandoned oil and gas wells (Ankleshwar, IIT Madras project) skip the most expensive and risky step, the first drilling [1][3][6].

• A balanced verdict for an answer

• Geothermal is a niche baseload and heating source worth supporting where the heat is proven. It is not a replacement for solar and wind at national scale.

12. Who Should Do What Next

• MNRE should share the cost of the first wells
• Every country in the World Bank survey that grew geothermal used some public support for early drilling [6].
• The US ran cost-shared drilling from 1981 to 2013, alongside tax credits [6]. Turkey and Kenya had the state drill first [6].

• A drilling-risk fund under the 2025 policy would deal with the barrier that stopped Tattapani [7][8].

• GSI and MNRE should publish drilling data, not just maps

• Turkey's MTA inventory and early wells are what drew private developers in [6].

• The policy's national data repository [1] should include temperature and flow data from every test well, including Puga's.

• Keep the support steady until the sector stands on its own

• Japan ended support in 2002 and stalled for nearly 20 years [6]. A pilot-only approach risks repeating that.

• Plan the power line along with the well

• Kenya treated transmission as part of the programme [6]. Australia's best sites were stuck far from the grid [6].

• For Puga, decide early whether the output will feed the grid or serve local heating and power, and build for that.

• Use oil and coal companies' skills on purpose

• ONGC Energy Centre (Puga), SCCL (Manuguru) and the abandoned-well pilots [1][4] fit the Philippines model, where a state oil company built a geothermal arm [6].

13. Anchors for Answers

• Data: 10.6 GW theoretical potential vs zero commercial geothermal power in India [1]; first-round exploration of 3–5 wells costs US$20–30 million [6]; global potential of 70–80 GW, of which only about 12 GW was in use [6]
• Report/Committee: World Bank ESMAP, Comparative Analysis of Approaches to Geothermal Resource Risk Mitigation: A Global Survey (Knowledge Series 024/16, 2016) [6]; World Bank/ESMAP Geothermal Handbook (2012) [10]
• Law/Case: No dedicated Act; National Policy on Geothermal Energy, 15 September 2025 [2]; compare Turkey's Renewable Energy Law with a feed-in tariff [6]
• Comparison: Turkey's survey agency drilled first and private firms followed [6]; Japan stalled at 536 MW for about 20 years after ending cost-shared drilling in 2002 [6]
• Scheme: MNRE's RE-RTD programme for indigenous geothermal technology [1]; Coal CPSE diversification (SCCL Manuguru 20 kW pilot) [4]

14. Mains Relevance

• GS-I: Physical geography (Earth's interior, distribution of key natural resources across India).
• GS-III: Infrastructure (energy); environment and conservation; science and technology (indigenisation of technology).
• Possible questions: 1. Geothermal energy offers India a baseload renewable option, yet it remains at the demonstration stage. Examine the potential and constraints in light of the National Policy on Geothermal Energy, 2025. 2. Discuss the significance of repurposing abandoned oil and gas wells for geothermal energy in India's clean energy transition. 3. Explain the geological basis for geothermal hotspots in India. How can direct-use applications benefit Himalayan regions?

15. Related Topics to Study Next

• Earth's interior and plate tectonics: the geological basis of geothermal hotspots and rift basins.
• Hot springs and geothermal provinces of India (Puga, Manikaran, Tattapani and others): mapping-based questions.
• Net Zero 2070 and India's NDCs: the policy anchor for diversifying renewables.
• Green hydrogen mission: baseload renewables as a possible input.
• Carbon capture, utilisation and storage (CCUS): also reuses old oil and gas wells and reservoirs.
• Ladakh's carbon-neutral vision and high-altitude energy access: the local setting of Puga.
• Coal CPSE diversification: SCCL's geothermal pilot as an example of energy transition.

16. NCERT Concepts to Revise

• Geothermal energy (Geography): The note's core subject: heat from the earth's interior, with Puga Valley in Ladakh as a prospect.
• Convection currents (Geography): Explains how radioactive and residual heat moves in the mantle, the geological basis of geothermal hotspots.
• Mantle (Geography): The largest, semi-solid layer of the earth's interior, which holds the heat that geothermal energy taps.
• Feed-in tariff (Economy): The guaranteed-price tool the note says pays only after a plant runs, so it fails to fund risky first drilling.
• Net zero (Economy): India's Net Zero 2070 target is the policy reason for the 2025 geothermal policy.
• Oil and Natural Gas Commission (Geography): ONGC drilled the Puga wells, and its oil-drilling skill and old wells are what geothermal reuse builds on.

17. Common Errors / Trap Areas

• Wrong ministry: the nodal ministry is MNRE. MoPNG, DGH and ONGC were consulted and run wells, but they do not lead the policy [2].
• Potential versus installed capacity: 10.6 GW is a theoretical figure. India has no commercial geothermal power yet [1].
• "381" wording: one PIB source says "381 hot springs" and another says "381 areas explored". Either way, the agency is GSI [1][3].
• Manuguru versus Puga: Manuguru is a 20 kW SCCL/Ministry of Coal pilot plant in Telangana. Puga holds the first geothermal wells, built by ONGC Energy Centre in Ladakh [1][4].
• Policy versus Act: the 2025 instrument is a policy, not legislation [2].