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Subject: Renewable Energy Technology

  • Deep-sea discovery, environmental responsibility

    Deep-sea discovery, environmental responsibility

    Why in the News

    India holds three International Seabed Authority (ISA) exploration contracts covering approximately 95,000 square kilometres across the Central Indian Ocean Basin, the Central Indian Ridge and the Carlsberg Ridge in the international seabed area. Its exploration has identified an estimated 366 million tonnes of polymetallic nodules containing nickel, copper, cobalt and manganese. Under the Deep Ocean Mission, deep sea mining technology, underwater robotics and the MATSYA 6000 human submersible are being developed. The case now put is that this capability raises a prior question rather than settling one: whether everything that can be technologically exploited should necessarily be exploited. The counter position is that these minerals carry legitimate strategic importance for India’s renewable energy, electric mobility and advanced manufacturing ambitions. The tension is between a demonstrated technical capability and an ecosystem whose functioning is not understood well enough to predict what large scale disturbance would do to it.

    What is deep sea mining of polymetallic nodules?

    1. Polymetallic nodules: Mineral concretions the size of a potato that lie loose on the abyssal seabed at depths of roughly 4,000 to 6,000 metres, formed over millions of years as metals precipitate around a nucleus.
    2. Why they are wanted: They carry nickel, copper, cobalt and manganese, the metals used in battery cathodes and in alloys, which ties the deposits to the energy transition.
    3. How collection works: A seabed crawler lifts the nodules off the sediment surface. The nodules are then raised through a riser pipe to a surface vessel, and the sediment and water drawn up with them are discharged back into the water column.
    4. Where the activity is regulated: Mineral activity on the seabed beyond national jurisdiction is administered by the International Seabed Authority, which issues exploration contracts and has not yet finalised the rules for commercial exploitation.

    What does India’s deep ocean research actually show?

    1. Biodiversity surveys: Surveys across 19 seamounts have studied around 1,300 deep sea organisms.
    2. Species new to science: Nearly 23 of those organisms have been reported as new to science.
    3. Mining technology tested: The National Institute of Ocean Technology has tested a mining machine at a depth of about 5,270 metres.
    4. Environmental baselines built alongside: The exploration work has been accompanied by extensive environmental and biodiversity studies rather than resource assessment alone.
    5. The standing gap: The research continues to reveal previously unknown organisms, so the consequences of large scale seabed disturbance cannot be confidently predicted while the inventory remains incomplete.

    Why does strategic importance not settle the question of extraction?

    1. Capability is not permission: Technological progress creates the assumption that what can be exploited should be exploited, and the deep ocean is the case where that assumption does not hold.
    2. The necessity test: Before extraction is considered, the questions are whether the minerals are genuinely necessary at the proposed scale, whether alternatives exist, and whether demand can be reduced.
    3. The demand side routes: Recycling, efficiency, substitution and a circular economy each reduce the quantity of primary metal required, so the case for extraction has to be made against them rather than in their absence.
    4. Where the burden sits: Necessity must be demonstrated rather than presumed, which places the onus on the party proposing extraction rather than on the party opposing it.
    5. Exploration is separable from exploitation: Investment in deep ocean science advances knowledge, biodiversity assessment, environmental baselines and technology without committing the country to commercial mining.

    Why can adaptive management not substitute for the decision itself?

    1. The nature of the disturbance: Mining physically disturbs the seabed, so the damage follows from the activity itself rather than from how carefully it is run.
    2. Limits of adaptive management: Adjusting practice in response to observed harm requires a baseline against which harm can be detected, and the baseline for these ecosystems is incomplete.
    3. Irreversibility: Nodules form over geological time, so the hard substrate they provide is not recreated within any management horizon a contract could set.
    4. The question restated: The operative question is not how to mine with minimum damage but whether there is a need to mine at all.
    5. Why the timing matters: India’s ISA activities remain at the exploration stage, so a high ecological threshold can be fixed before any commercial decision rather than negotiated after one.

    What would leadership on deep sea ecological governance involve?

    1. Recognising ecological value: Treating the deep ocean as a precious ecological asset whose value may exceed that of its mineral wealth, rather than as a mineral reserve alone.
    2. Using the Mission’s own findings: The knowledge generated under the Deep Ocean Mission can support a conclusion that some poorly understood and potentially irreversible ecosystems are better left undisturbed.
    3. Mission LiFE as the domestic anchor: Lower demand, resource efficiency, recycling, substitution and circular consumption already sit in Mission LiFE, so the position has a stated domestic policy basis.
    4. Alignment with existing frameworks: Nature based Solutions, the Sustainable Development Goals (SDGs) and the circular economy share the principle that nature is the capital on which development depends.
    5. The role of science: Science establishes not only how far a country can go but also where it must stop, so identifying the frontiers best left untouched is part of its function.

    Challenges to deep sea mining governance

    1. The exploitation rules are unfinished: The International Seabed Authority has not adopted the regulations for commercial recovery, so there is no agreed standard for environmental thresholds, monitoring or liability. Eg. The two year rule triggered by Nauru in 2021 forced the Authority to face applications even without a completed code.
      The Fix: Hold commercial applications until the exploitation regulations and a liability regime are adopted, and argue that position at the Authority’s Council.
    2. The sponsoring State carries the liability: A contractor operates under the sponsorship of a State, which bears responsibility for ensuring compliance, so a private failure becomes a sovereign exposure. Eg. The International Tribunal for the Law of the Sea advisory opinion of 2011 set out the due diligence obligations of States sponsoring activity in the Area.
      The Fix: Require every sponsored contractor to post an environmental bond and accept independent monitoring before a sponsorship certificate issues.
    3. Sediment plumes travel beyond the mine site: Collection stirs fine sediment that drifts across the seabed, and the discharge from the surface vessel spreads through the water column, so effects extend past the licensed block. Eg. Tracks left by an experimental seabed disturbance in the Peru Basin in 1989 were still visible decades later with little faunal recovery.
      The Fix: Mandate plume modelling and independent monitoring across an agreed buffer around every test and production site.
    4. Recovery time exceeds any contract term: Nodule fields and the organisms attached to them re form over millions of years, so a disturbed area is lost for the purposes of any human management cycle. Eg. Sponges, corals and other attached species in the Clarion Clipperton Zone depend on the hard nodule surface as their only available substrate.
      The Fix: Designate no mining reference zones of ecological significance inside each contract area before exploitation is licensed, not after.
    5. India has no domestic law for activity in the Area: The Offshore Areas Mineral (Development and Regulation) Act, 2002 governs India’s own offshore areas, while activity in the international seabed area is covered only by contract conditions. Eg. India’s exploration contracts sit beyond national jurisdiction, where domestic environmental clearance procedures do not apply at all.
      The Fix: Enact a domestic statute fixing environmental assessment, monitoring and liability standards for Indian entities operating in the Area.
    6. Demand forecasts may not survive a change in battery chemistry: The commercial case for nodules rests on nickel and cobalt demand, which falls as cell chemistries shift away from those metals. Eg. Lithium iron phosphate (LFP) cells use neither nickel nor cobalt and have taken a growing share of electric vehicle batteries.
      The Fix: Tie any extraction decision to a periodically revised national critical mineral demand assessment that accounts for substitution and recycling.

    Conclusion

    India’s position on the seabed is unusual in that it holds the contracts and the technology to use them, and has not yet taken a decision to exploit. That interval is where an ecological threshold can be written in as a condition rather than conceded later as a compromise. The two commitments pull against each other, since the same mineral demand the energy transition generates is what makes the seabed attractive, and reducing that demand is what would make the seabed unnecessary. The point to watch is what India argues when the rules for commercial recovery come to a decision at the Authority, because that is where a principle has to become a stated national position.

    Government Initiatives for deep ocean science and the blue economy

    1. Deep Ocean Mission: Launched in 2021 under the Ministry of Earth Sciences with an outlay of about Rs 4,077 crore, it runs on six pillars covering deep sea mining technology and a manned submersible, ocean climate change advisory services, technologies for deep sea biodiversity, ocean survey and exploration, energy and freshwater from the ocean, and an advanced marine station for ocean biology.
    2. Samudrayaan: The manned ocean mission under the Deep Ocean Mission, designed to take a crew to a depth of 6,000 metres in the MATSYA 6000 submersible.
    3. O SMART: The Ocean Services, Modelling, Application, Resources and Technology scheme, which funds ocean observation, forecasting and marine resource services.
    4. National Centre for Polar and Ocean Research: Headquartered in Goa, it runs India’s polar and Southern Ocean research programmes and supports ocean science campaigns.
    5. Deccan High Level Principles on Blue Economy: Adopted at Chennai under India’s G20 Presidency in 2023, they set out an agreed framework for sustainable ocean management.

    Back2Basics: International Seabed Authority (ISA)

    1. What it is: An autonomous international organisation established under the United Nations Convention on the Law of the Sea (UNCLOS), 1982 and its 1994 Implementation Agreement.
    2. Mandate: It organises and controls all mineral related activity in the Area, meaning the seabed and subsoil beyond the limits of national jurisdiction, which UNCLOS designates the common heritage of mankind.
    3. Membership and seat: It is headquartered in Kingston, Jamaica, and its membership comprises every State party to UNCLOS, India included.
    4. What it issues: It grants exploration contracts to State sponsored contractors and is still drafting the exploitation regulations, known as the Mining Code, that would govern commercial recovery.

    Matching Previous Year Question

    “[2026] Which of the following statements with regard to India’s Deep Ocean Mission is/are correct?

    1. It was launched by the Ministry of Ports, Shipping and Waterways, Government of India.

    2. Matsya-6000 has been designed to carry 3 people for deep sea exploration.

    3. Samudrayaan is a project under this mission.

    (a) 1 only

    (b) 2 and 3 only

    (c) 1 and 2 only

    (d) 1, 2 and 3 Answer: B”

  • Geothermal Energy

    Why in News

    A PIB Backgrounder on geothermal energy set out the resource, its potential in India, and its place in the clean energy transition.

    Core facts

    1. Definition: Geothermal energy is heat stored within the earth. It is drawn from hot rocks and hot water reservoirs below the surface and used for power generation and direct heating.
    2. Nature of the resource: Geothermal energy is a renewable and baseload source. It supplies power around the clock, unlike solar and wind, which vary with weather and time of day.

    Static Context

    1. India’s potential: The Geological Survey of India (GSI) has identified about 340 geothermal hot spring sites. The estimated geothermal power potential is placed around 10,600 megawatts (MW).
    2. Key geothermal provinces: Major sites include Puga and Chhumathang in Ladakh, Tattapani in Chhattisgarh, Manikaran in Himachal Pradesh, and the Godavari and Cambay basins.
    3. How it works: A geothermal plant taps steam or hot water from a well. The steam drives a turbine. The turbine drives a generator to produce electricity.
    4. Uses beyond power: Direct use includes space heating, greenhouse warming, aquaculture and cold storage. Ladakh has seen pilot efforts for geothermal power and heating.
    5. Nodal ministry: The Ministry of New and Renewable Energy (MNRE) is the nodal ministry for renewable energy sources, including geothermal.
    6. Global comparison: Countries with high geothermal output include the United States, Indonesia, the Philippines, Iceland and Kenya. India’s geothermal capacity remains at an early stage.

    Prelims angle

    1. The location of Puga, Tattapani, Manikaran and other geothermal sites, and the role of the Geological Survey of India in resource mapping.
    2. The classification of geothermal as a renewable and baseload source, and the nodal ministry. Site to state matching is a common format.

    Mains angle

    1. GS Paper 3, infrastructure and energy, and India’s renewable energy mix.
    2. A question can ask how baseload renewable sources such as geothermal complement variable solar and wind in the path to energy security.

    Matching Previous Year Question

    “[2022, GS3, 15] Do you think India will meet 50 percent of its energy needs from renewable energy by 2030 ? Justify your answer. How will the shift of subsidies from fossil fuels to renewables help achieve the above objective? Explain.”

  • Geothermal Energy

    Geothermal Energy

    Why in News

    The Press Information Bureau (PIB) published a thematic Backgrounder on Geothermal Energy on 4 September 2026. The piece is a subject explainer written for exam and public awareness value.

    Core facts

    1. Definition: Geothermal energy is heat stored inside the Earth. This heat is tapped through wells at sites with high underground temperature gradients.
    2. Nature of the source: Geothermal power is a renewable and baseload source. It generates around the clock, unlike solar or wind.
    3. Nodal ministry: The Ministry of New and Renewable Energy (MNRE) is the nodal ministry for geothermal energy in India.
    4. Verification note: The release body did not resolve on the source page this run, so release-specific figures are not quoted. The static estimates below come from standard reference data.

    Static Context

    1. India’s first project: India commissioned its first geothermal wells at Puga Valley in the Changthang region of Ladakh. A 1 Megawatt (MW) pilot geothermal plant is planned as the first demonstration scale project.
    2. Implementing agency: The ONGC Energy Centre, a body of the Oil and Natural Gas Corporation (ONGC), leads the Puga project with the Ladakh Administration.
    3. Estimated potential: India’s geothermal potential is estimated at about 10,600 MW (standard reference figure).
    4. Survey base: The Geological Survey of India (GSI) has documented about 381 hot springs. India has ten geothermal provinces, including the Himalayan, Son Narmada Tapi (SONATA), West Coast, Cambay and Godavari belts.
    5. Key sites: Notable geothermal sites include Puga and Chumathang in Ladakh, Manikaran in Himachal Pradesh, Tattapani in Chhattisgarh, and Bakreshwar in West Bengal.
    6. Policy frame: A National Policy on Geothermal Energy was notified in 2025, with the MNRE as the promoting authority.

    Prelims angle

    1. Nodal ministry: MNRE. Lead agency for Puga: ONGC Energy Centre.
    2. First site: Puga Valley, Ladakh. Survey body: GSI, with about 381 hot springs mapped.
    3. Source character: Renewable and baseload, driven by internal Earth heat.
    4. Geothermal provinces: Himalayan, SONATA, West Coast, Cambay, Godavari and others.

    Mains angle

    GS Paper 3, energy and infrastructure. A question can ask how geothermal energy can add firm renewable baseload capacity to India’s energy mix, and can weigh the high exploration cost and site concentration in the Himalayas against the round the clock output advantage.

    “[2013] Consider the following :

    (1). Electromagnetic radiation

    (2). Geothermal energy

    (3). Gravitational force

    (4). Plate movements

    (5). Rotation of the earth

    (6). Revolution of the earth

    Which of the above are responsible for bringing dynamic changes on the surface of the earth?

    (a) 1, 2, 3 and 4 only

    (b) 1, 3, 5 and 6 only

    (c) 2, 4, 5 and 6 only

    (d) 1, 2, 3, 4. 5 and 6.

  • No takers for govt’s ₹37,500-crore coal gasification scheme

    Why in the News

    The coal ministry’s ₹37,500 crore financial incentive scheme for surface coal and lignite gasification has drawn no application from any private or public player. The last date for submission is 7 September 2026, fixed by a Request for Proposal issued on 7 July 2026. The Union Cabinet had approved the scheme to gasify 75 million tonnes of coal and lignite and to cut imports of liquefied natural gas, urea and methanol. The ministry attributes the absence of bids to the time a project proposal of this scale takes to prepare. An incentive of this size drawing nothing at its first deadline points at the economics of a gasification project rather than at the paperwork.

    How does coal gasification work?

    1. From solid fuel to gas: Dry fuel is converted into synthetic gas, known as syngas.
    2. What syngas is used for: Syngas serves as an alternative fuel and as the feedstock for methanol, fertilisers, hydrogen and chemicals.
    3. The stated emissions gain: Converting coal into gas rather than burning it directly is counted as a reduction in carbon emissions.

    What was the scheme designed to achieve?

    1. A volume target: The programme is built around gasifying 75 million tonnes of coal and lignite.
    2. Import substitution: The scheme is aimed at reducing dependence on imports of liquefied natural gas, urea and methanol.
    3. Insulation from external shocks: Domestic production of these inputs is intended to shield the country from global price volatility and supply chain disruption.
    4. The instrument: A financial outlay of ₹37,500 crore was approved for surface coal and lignite gasification projects.

    How has the coal ministry explained the empty first round?

    1. Proposal preparation takes time: Given the scale of funds each project involves, the preparation of pre-feasibility reports and project proposals runs long.
    2. Interest without applications: Several industries have communicated their interest in participating, and none has filed.
    3. The count is not final: The number of applications cannot be stated before the deadline passes, since submission is entirely online.
    4. The window reopens: Application rounds are envisaged every two months, giving industry repeated opportunities to enter.

    Challenges to the coal gasification incentive scheme

    1. High ash domestic coal raises the cost: Indian coal carries a high ash content, which lowers gas yield per tonne and raises the capital cost of the gasifier. Eg. Gasifier designs proven on low ash imported coal need modification before they run on Indian coal.
      The Fix: Tie the incentive to a gasifier configuration demonstrated on high ash domestic coal, rather than to project cost alone.
    2. The output price is set by policy, not by the market: Urea sold to farmers carries a maximum retail price fixed by the Centre, so a coal based producer’s revenue depends on the subsidy regime. Eg. Urea remains outside the Nutrient Based Subsidy regime and continues to be sold at a controlled price.
      The Fix: Offer a long term offtake price for coal based urea and methanol, so a project’s revenue is known before financial closure.
    3. No assured buyer for the other outputs: Lenders fund a plant only where a committed purchaser exists for its methanol or hydrogen. Eg. India has no binding methanol blending obligation comparable to the dated targets under the ethanol blending programme.
      The Fix: Notify a methanol blending obligation with dated targets, so demand exists independently of the capital subsidy.
    4. A coal based route to a fuel sold as clean: The process begins with coal, so the emissions case rests on capturing the carbon dioxide the process concentrates. Eg. Coal to methanol carries higher lifecycle emissions than natural gas based methanol.
      The Fix: Make carbon capture capability a condition of the incentive rather than an optional addition.
    5. Clearances have to be assembled before a bid: A promoter needs a coal linkage, land and water in place before a proposal is fileable, and the incentive supplies none of them. Eg. The Talcher Fertilizers coal to urea project in Odisha has run well past its original commissioning timeline.
      The Fix: Bundle a coal linkage and a land allotment with the incentive award, so a bidder is not chasing clearances and funding at the same time.

    Conclusion

    The obstacle here is not the size of the incentive but the absence of a price and a buyer for what a gasification plant would make. A capital subsidy lowers the cost of building the plant. It does not tell the promoter what the output will sell for, or who is obliged to buy it. The marker to watch is whether the next round is paired with an assured offtake price or a blending obligation, and whether a public sector energy company files before any private promoter does.

    Back2Basics: Lignite

    1. What it is: Lignite is the lowest rank of coal, high in moisture and low in fixed carbon, also called brown coal.
    2. Why it is used near the mine: Its calorific value is lower than that of bituminous coal, so transporting it long distances is uneconomic and it is burned or gasified close to the pithead.
    3. Where India’s reserves lie: The bulk of the country’s lignite sits in Tamil Nadu, with further deposits in Rajasthan, Gujarat and Jammu and Kashmir.
    4. Who mines it: NLC India Limited, a central public sector enterprise under the Ministry of Coal, is the largest lignite producer in the country.

    [2025] Consider the following substances:

    I. Ethanol

    II. Nitroglycerine

    III. Urea

    Coal gasification technology can be used in the production of how many of them?

    (a) Only one

    (b) Only two

    (c) All three

    (d) None

  • Consider the following

    Consider the following:
    1. Battery storage
    2. Biomass generators
    3. Fuel cells
    4. Rooftop solar photovoltaic units
    How many of the above are considered “Distributed Energy Resources”?

  • Catalyst that Transforms to Perform

    Why in the news?

    Scientists from the Centre for Nano and Soft Matter Sciences and collaborating institutions discovered how a catalyst changes its structure during water electrolysis for green hydrogen production. The study was published in Materials Horizons.

    Key Highlights

    • Researchers studied:
      • Molybdenum carbide (Mo₂C), an earth-abundant catalyst used in hydrogen production.
    • Molybdenum Carbide is a compound made of molybdenum and carbon that acts as an efficient catalyst in hydrogen production and other industrial chemical reactions
    • Key Features
      • Considered an earth-abundant catalyst because molybdenum is more available and cheaper than precious metals like platinum.
      • Exhibits platinum-like catalytic properties in some reactions.
      • Has high thermal stability and good electrical conductivity.
    • Role in Hydrogen Production
      • Mo₂C is widely studied for: Hydrogen Evolution Reaction (HER) in water splitting.
      • Electrochemical production of green hydrogen.
      • Improving efficiency while reducing dependence on expensive noble-metal catalysts.

    About Hydrogen Evolution Reaction (HER)

    • HER is the electrochemical reaction where hydrogen gas is produced from water during electrolysis.
    • It occurs at the cathode. (The cathode is the electrode where reduction occurs and hydrogen gas is produced.)
      • Note: Anode: The anode is the electrode where oxidation occurs. In water electrolysis, oxygen is produced at the anode through the Oxygen Evolution Reaction (OER).
    • Efficient catalysts are required to reduce energy consumption and improve hydrogen production efficiency.

    About Green Hydrogen

    • Green hydrogen is hydrogen produced using renewable energy sources through electrolysis of water.
    • It is considered a clean fuel because it emits no carbon dioxide during use.

    [2023] With reference to green hydrogen, consider the following statements:
    1. It can be used directly as a fuel for internal combustion.
    2. It can be blended with natural gas and used as fuel for heat or power generation.
    3. It can be used in the hydrogen fuel cell to run vehicles.
    How many of the above statements are correct?

    [A] Only one

    [B] Only two

    [C] All three

    [D] None

  • Which of the following pairs in respect of power generation in India is/are correctly matched

    Which of the following pairs in respect of power generation in India is/are correctly matched?
    1. Installed electricity generation capacity: 100000 MW
    2. Electricity generation: 660 billion kWh.

  • Recently, “oilzapper’’ was in the news. What is it

    Recently, “oilzapper’’ was in the news. What is it?

  • Microbial fuel cells are considered a source of sustainable energy. Why? 1. They use living organisms as catalysts to generate electricity from certain substrates.

    Microbial fuel cells are considered a source of sustainable energy. Why? 1. They use living organisms as catalysts to generate electricity from certain substrates.
    2. They use a variety of inorganic materials as substrates.
    3. They can be installed in wastewater treatment plants to cleanse water and produce electricity.

  • With reference to technology for solar power production, consider the following statements

    With reference to technology for solar power production, consider the following statements:
    1. ‘Photovoltaics’ is a technology that generates electricity by direct conversion of light into electricity, while ‘Solar Thermal’ is a technology that utilizes the Sun’s rays to generate heat which is further used in electricity generation process.
    2. Photovoltaics-generates Alternating Current (AC), while Solar Thermal generates Direct Current (DC).
    3. India has manufacturing base for Solar Thermal technology, but not for photovoltaics.
    Select the correct answer using the code given below: