Renewable Energy Sources in India – Solar, Wind, and Beyond

Renewable Energy Sources in India (Solar, Wind, Hydro, Biomass) — UPSC Prelims + Mains (Updated with 2024–2025 Data)

Renewable energy means energy that comes from natural sources which get replenished quickly, like sunlight, wind, flowing water, plant material, and heat from the Earth. For India, renewables are not only an "environment" topic. They are also a core "economy + security" topic because India imports a large share of its fossil fuels. More renewables can reduce import dependence, cut pollution, create jobs, and support new industries like batteries, green hydrogen, and clean manufacturing.

In UPSC, renewable energy questions are asked in both Prelims and Mains. Prelims focuses on definitions, schemes, institutions, matching, and factual trends. Mains expects you to explain the "why + how": why India is pushing renewables, how each source works, what the challenges are (grid, land, finance), and what policy solutions are practical.

1) India's Renewable Energy Targets (Must Remember for UPSC)

500 GW (non-fossil energy capacity) by 2030 and Net Zero by 2070 were announced as part of India's "Panchamrit" commitments at COP26.

These targets matter because they create long-term demand for clean power and related infrastructure like transmission lines, storage, electric mobility, and green hydrogen. For Mains, you should also note that achieving these targets is not only about adding solar and wind. It also needs grid strengthening, flexible generation, better DISCOM finances, and stable policy signals.

2) Latest Installed Renewable Energy Capacity in India (2024–2025 Data)

As per the Ministry of New and Renewable Energy (MNRE) physical progress data, India's cumulative renewable energy capacity as on 31.12.2025 is about 258.01 GW. This includes solar, wind, biomass/bio-power, small hydro, large hydro, and waste-to-energy.

Technology-wise capacity (as on 31.12.2025): Solar 135.81 GW, Wind 54.51 GW, Small Hydro 5.16 GW, Large Hydro 50.91 GW. Bio-power (biomass + bagasse + waste-to-energy combined) is reflected within MNRE bio-power totals in state-wise tables.

MNRE also provides the composition inside solar: Ground-mounted solar is about 103.24 GW and grid-connected rooftop solar is about 23.62 GW (as on 31.12.2025).

3) Mandatory Definition Boxes (10) — Read Like Prelims Notes

2. Solar Energy (Photovoltaic) — How Solar PV Cells Work

Solar PV converts sunlight directly into electricity. A PV cell is usually made of semiconductor material (commonly silicon). When sunlight (photons) hits the cell, it knocks electrons loose. Because the cell is designed with a p-n junction, these electrons move in one direction, creating direct current (DC). An inverter converts DC into alternating current (AC) for household and grid use. Solar PV output depends on sunlight, temperature, dust, and panel orientation. Solar is modular: it works from small rooftops to large solar parks.

10. Energy Storage Systems — Batteries, Pumped Hydro, Hydrogen Storage

Energy Storage Systems (ESS) store energy when supply is high and release it when demand is high. Storage is crucial because solar and wind are variable. Main types are: (1) batteries (like lithium-ion) for fast response and short-to-medium duration, (2) pumped storage hydropower for long-duration bulk storage, and (3) hydrogen storage for seasonal or industrial-scale storage. In India's hydro data, large hydro includes pumped storage capacity.

4) Solar Energy in India (UPSC Depth)

Solar energy is the backbone of India's renewable capacity growth. MNRE data shows solar has reached 135.81 GW as on 31.12.2025.

4.1 Why Solar Fits India

• High solar irradiation across many states, especially western and southern India.
• Modular nature: from a 1–3 kW rooftop system to a multi-GW solar park.
• Fast construction: solar projects can be built quicker than large dams or thermal plants.
• Daytime supply: helps meet summer daytime demand (cooling, agriculture pumps, commercial loads).

4.2 National Solar Mission and Solar Overview

MNRE describes the National Solar Mission (NSM) as a major initiative to promote solar energy diffusion across the country quickly, while supporting energy security and sustainable growth.

4.3 Solar Parks (Bhadla, Pavagada) — UPSC "Place + Scheme" Combo

Solar Parks reduce project risk by providing land, evacuation infrastructure, and a plug-and-play ecosystem. Two classic examples frequently used in UPSC answers are:

• Bhadla Solar Park (Rajasthan): about 2245 MW.
• Pavagada Solar Park (Karnataka): about 2050 MW.

For Mains, mention why solar parks matter: land aggregation, reduced delays, common transmission, faster scaling, and lower tariffs due to competition and reduced uncertainty.

4.4 Rooftop Solar (RTS) and Grid-Connected Rooftop Solar Programme

Rooftop solar is important because it creates electricity close to where it is consumed. This reduces transmission losses and can reduce peak load for DISCOMs if managed well.

MNRE's Grid Connected Rooftop Solar Programme aims to achieve a cumulative installed capacity of 40,000 MW from grid-connected rooftop solar projects, and the Phase-II scheme period is extended till 31.03.2026.

In capacity terms, MNRE indicates rooftop solar (grid-connected rooftop) is about 23.62 GW as on 31.12.2025.

4.5 PM-KUSUM (Solar in Agriculture) — Very High UPSC Value

PM-KUSUM connects renewable energy with farmers' income, irrigation, and feeder-level power reform. MNRE states the scheme aims to add 34,800 MW solar capacity by March 2026 and explains three components (A, B, C).

• Component-A: Decentralized grid-connected renewable plants (often solar) set up by farmers/communities.
• Component-B: Standalone solar agricultural pumps.
• Component-C: Solarisation of existing grid-connected agriculture pumps / feeders.

4.6 Solar Challenges (Write These in Mains)

• Intermittency: solar output drops in evening and during cloudy conditions.
• Land acquisition and land use conflicts for large solar parks (need agrivoltaics and wasteland planning).
• Grid integration: needs forecasting, flexible generation, and storage to avoid curtailment.
• Distribution-level constraints for rooftop: transformer capacity, net metering rules, process delays.
• Financing cost: interest rates and payment delays from DISCOMs increase project risk.

5) Wind Energy in India (Corridors, Potential, and Issues)

Wind is India's second-biggest renewable contributor after solar. MNRE reports wind capacity as 54.51 GW as on 31.12.2025.

5.1 Wind Corridors (Gujarat, Tamil Nadu, Maharashtra and others)

India's best wind regions are concentrated in a few corridors. Gujarat and Tamil Nadu are the largest wind states by installed capacity, followed by Karnataka and Maharashtra, as shown in MNRE's state-wise installed capacity data (31.12.2025).

MNRE also publishes wind potential estimates by state (for example, at 120 m and 150 m hub heights), showing major potential in states like Andhra Pradesh, Gujarat, Karnataka, Maharashtra, Rajasthan, and Tamil Nadu.

5.2 Onshore vs Offshore Wind (UPSC Understanding)

• Onshore wind: cheaper, easier to build, but best land sites are limited and may face local opposition.
• Offshore wind: steadier winds, better capacity factors, but high cost, complex approvals, and marine ecosystem concerns.

5.3 Key Challenges in Wind

• Site saturation in best corridors and the need for repowering (replacing old small turbines with modern larger turbines).
• Transmission bottlenecks from wind-rich zones to demand centers.
• Policy and contracting delays (tendering, PPA signing, payment security).
• Variability (seasonal and hourly) requiring forecasting and balancing resources.

6) Hydropower in India (Large Hydro, Small Hydro, Pumped Storage)

Hydropower is important not only for "renewable capacity" but also for grid stability. It can provide peaking power and frequency support, which becomes more valuable when solar and wind share rises.

6.1 Classification (25 MW Rule)

In India, hydropower plants with capacity of 25 MW or below are classified as Small Hydro.

6.2 India's Installed Hydro Capacity (2024–2025 data)

MNRE reports (as on 31.12.2025): Large Hydro about 50.91 GW and Small Hydro about 5.16 GW.

MNRE notes that large hydro includes pumped storage capacity (about 7175.6 MW) within the large hydro number.

6.3 Pumped Storage Hydropower (PSH) — The "Grid Battery" Concept

Pumped storage is a proven long-duration storage method. It uses cheap or surplus electricity to pump water uphill, and later releases it to generate electricity during peak demand. This is why pumped storage is increasingly discussed as a solution for renewable integration.

6.4 Hydropower Benefits

• Peaking power and grid balancing for solar and wind.
• Low operating cost once built.
• Long project life compared to many other power assets.

6.5 Hydropower Concerns (Write Balanced Answers)

• Ecological impact: river flow change, fish migration issues, biodiversity loss.
• Social impact: displacement, rehabilitation challenges.
• Sedimentation reduces reservoir capacity over time.
• Climate risks in Himalayas: extreme rainfall events, glacial lake risks, landslides.

7) Biomass Energy and Biofuels in India (Biomass Power, SATAT, Ethanol Blending)

Biomass is a unique renewable source because it sits at the intersection of energy + agriculture + waste management. It can also provide more "dispatchable" power than solar and wind if the fuel supply is stable.

7.1 Biomass Power and Bagasse Cogeneration

Bagasse cogeneration is especially important in sugarcane states (like Maharashtra, Uttar Pradesh, Karnataka, Tamil Nadu). Sugar mills can generate electricity using bagasse and sometimes export surplus power to the grid. MNRE's state-wise data (as on 31.12.2025) shows bio-power (including bagasse, non-bagasse, and waste-to-energy) totals across states and a national bio-power total of about 11.61 GW.

7.2 SATAT (Compressed Biogas / CBG) — Biomass to Transport Fuel

SATAT (Sustainable Alternative Towards Affordable Transportation) promotes production and utilization of Compressed Bio Gas (CBG), creating an ecosystem for CBG as a transport and industrial fuel. A government year-end review notes that SATAT was launched on 1 October 2018 to promote production and use of CBG.

Why SATAT matters for UPSC:

• Helps manage organic waste and cattle dung.
• Supports farmers through new income streams (waste → energy).
• Reduces dependence on imported natural gas and crude oil products.

7.3 Ethanol Blending Programme (E20) — Target and Latest Progress

Ethanol blending is a major biofuel policy because it links agriculture (sugarcane, grains, biomass) with fuel security. PIB notes that India achieved 15% ethanol blending in 2024 and targets 20% by 2025.

In 2025, the government reported that during the ongoing Ethanol Supply Year (ESY 2024–25), Oil Marketing Companies achieved an average blending of 19.05% as on 31.07.2025, and 19.93% blending was achieved in July 2025.

Another PIB release states that the target of 20% blending (E20) by 2025 has already been achieved in the current Ethanol Supply Year.

7.4 Benefits of Biomass and Biofuels (Write in Mains)

• Energy security: replaces part of petrol/diesel/gas use.
• Rural income: creates markets for residue and organic waste.
• Waste management: supports circular economy.
• Potential pollution reduction if managed with modern emission controls and sustainable feedstock.

7.5 Risks and Challenges (Important for Balanced Mains Answers)

• Feedstock supply chain: collection, storage, transport can be costly.
• Competing uses: residues may be needed for fodder, compost, or soil health.
• Air pollution concerns if biomass is burnt inefficiently (need strict emission standards).
• Water and land stress concerns if biofuel feedstocks expand unsustainably.

8) Geothermal Energy in India (Emerging but Important)

Geothermal energy is not yet a big part of India's installed capacity, but UPSC may ask it because India has identified potential sites and has begun policy focus. MNRE notes geothermal as a 24×7 renewable source and mentions India's tentative potential around 10 GW.

Government information in 2024 also highlighted that GSI studied 381 thermally anomalous areas, published the Geothermal Atlas of India (2022), and estimated about 10,600 MW geothermal power potential.

Examples of geothermal hotspots you can mention in answers: Puga/Chumathang (Ladakh), Manikaran (Himachal Pradesh), Tattapani (Chhattisgarh), and other hot spring regions.

9) Green Hydrogen and Renewables (Solar/Wind → Hydrogen)

Green hydrogen is best understood as an energy carrier. It is produced using renewable electricity and then used where direct electrification is difficult. India's National Green Hydrogen Mission has an initial outlay of ₹19,744 crore.

MNRE states the mission targets 5 MMT green hydrogen production capacity per annum by 2030.

Major applications you can write in Mains:

• Fertilizers: green ammonia (reduce natural gas use).
• Refineries: replace grey hydrogen.
• Steel: green steel using hydrogen-based processes.
• Heavy transport: long-distance trucks, shipping (future), buses in pilots.
• Seasonal storage: convert surplus renewable power into hydrogen for later use.

10) Role of Key Institutions (MNRE, SECI, IREDA) — UPSC-Friendly Notes

MNRE is the nodal ministry for renewable energy policy, targets, schemes, standards, and coordination with states and other ministries.

SECI (Solar Energy Corporation of India) is a key implementing agency. SECI acts as a power procurement intermediary: it signs PPAs with renewable developers and PSAs with DISCOMs, helping provide payment security and scale up renewable procurement.

SECI is also associated with major initiatives under solar parks and has been linked with large projects such as 2245 MW Bhadla and 2050 MW Pavagada in its official brief.

IREDA (Indian Renewable Energy Development Agency) is a Government of India enterprise under MNRE and a non-banking financial institution. IREDA's role is to provide financial assistance for projects related to renewable energy and energy efficiency.

In simple words: MNRE sets direction, SECI helps execute and aggregate demand, and IREDA helps finance.

11) State-wise Renewable Energy Capacity Leaders (As on 31.12.2025)

UPSC often asks which states lead in solar and wind, and what explains the pattern. MNRE's state-wise installed capacity table (as on 31.12.2025) provides clear leaders.

11.1 Top States by Total Renewable Energy Capacity (Approximate Leaders)

• Gujarat: ~42.58 GW total RE
• Rajasthan: ~42.53 GW total RE
• Maharashtra: ~30.31 GW total RE
• Tamil Nadu: ~27.11 GW total RE
• Karnataka: ~25.98 GW total RE

These totals (and technology-wise splits) are from MNRE's state-wise table (31.12.2025).

11.2 Top States by Solar Capacity

• Rajasthan: ~36.66 GW solar
• Gujarat: ~25.53 GW solar
• Maharashtra: ~18.06 GW solar
• Tamil Nadu: ~11.66 GW solar
• Karnataka: ~10.68 GW solar

These figures are taken from MNRE state-wise installed capacity (31.12.2025).

11.3 Top States by Wind Capacity (Key Wind Corridors)

• Gujarat: ~14.82 GW wind
• Tamil Nadu: ~12.08 GW wind
• Karnataka: ~8.41 GW wind
• Maharashtra: ~5.82 GW wind
• Rajasthan: ~5.23 GW wind

This directly supports the UPSC statement: key wind corridors are in Gujarat, Tamil Nadu, Maharashtra (also Karnataka and Rajasthan).

11.4 Top Large Hydro States (Illustrative Leaders)

• Himachal Pradesh: ~11.42 GW large hydro
• Uttarakhand: ~4.79 GW large hydro
• Karnataka: ~3.69 GW large hydro
• Jammu & Kashmir: ~3.36 GW large hydro
• Andhra Pradesh: ~3.29 GW large hydro

These are from the MNRE state-wise RE installed capacity table (31.12.2025).

12) Two Mandatory Comparison Tables

12.1 Comparison Table 1 — Types of Renewable Energy Sources with Pros/Cons

12.2 Comparison Table 2 — India vs Global Renewable Energy Capacity (Latest Available)

Global renewable power capacity (end-2024) as per IRENA: 4,448 GW, including solar 1,865 GW, wind 1,133 GW, hydropower 1,283 GW, bioenergy 151 GW, geothermal 15 GW (marine ~0.5 GW).

India renewable capacity shown here is as on 31.12.2025 from MNRE.

13) Key Government Schemes to Mention in Mains

• National Solar Mission: policy push for solar diffusion nationwide.
• Solar Parks Scheme: enables large-scale solar through plug-and-play parks (Bhadla, Pavagada).
• Grid Connected Rooftop Solar Programme: objective of 40,000 MW rooftop; Phase-II extended till 31.03.2026.
• PM-KUSUM: decentralised solar for agriculture; target 34,800 MW by March 2026; components A, B, C.
• SATAT: ecosystem for Compressed Bio Gas (CBG), launched 1 Oct 2018.
• Ethanol Blended Petrol (EBP) Programme: targets E20, achieved major progress by ESY 2024–25.
• National Green Hydrogen Mission: ₹19,744 crore outlay; 5 MMT by 2030 target.

14) Core Challenges and Practical Solutions (Write This as a Mains "Way Forward")

14.1 Intermittency (Solar/Wind)

Problem: Solar and wind output changes with weather and time of day. Evening peak demand often comes when solar generation falls.

Solutions: storage (batteries, pumped storage), better forecasting, hybrid projects (wind + solar + storage), demand response, and stronger inter-state transmission.

14.2 Land Acquisition and Land Use

Problem: Large solar parks and wind farms need land. This can create conflicts with agriculture and local livelihoods.

Solutions: use wastelands where feasible, encourage agrivoltaics (dual land use), transparent land leasing models (like some solar parks), and faster but fair clearances.

14.3 Grid Integration and Transmission

Problem: Renewable projects are often far from demand centers. If transmission is delayed, power gets curtailed and projects become risky.

Solutions: green energy corridors, synchronized planning of generation and evacuation, and modern grid management (flexible dispatch, ancillary services).

14.4 Financing and DISCOM Payment Risk

Problem: Renewable projects are capital intensive. High interest rates and delayed payments hurt viability.

Solutions: stronger payment security mechanisms, predictable tendering, better DISCOM reforms, and specialized financing institutions like IREDA.

15) UPSC Previous Year Questions (3) — With Answers and Explanations

16) Practice MCQs (10) — 4 Options Each, Answers + Detailed Explanations

MCQ 1

Question: Which of the following best describes India's renewable energy capacity status as on 31.12.2025 (MNRE data)?

• (A) Solar is about 54.5 GW and wind is about 135.8 GW
• (B) Solar is about 135.8 GW and wind is about 54.5 GW
• (C) Solar is about 50.9 GW and large hydro is about 135.8 GW
• (D) Total renewable energy is less than 150 GW

Answer: (B)

Explanation: MNRE reports solar around 135.81 GW and wind around 54.51 GW as on 31.12.2025. Total renewable energy is about 258.01 GW, so options A, C, and D are incorrect.

MCQ 2

Question: In India, a hydropower project is classified as "Small Hydro" if its capacity is:

• (A) Below 10 MW
• (B) 25 MW or below
• (C) 50 MW or below
• (D) 100 MW or below

Answer: (B)

Explanation: MNRE states that in India, hydro power plants with capacity of 25 MW or below are classified as Small Hydro.

MCQ 3

Question: Which of the following statements about PM-KUSUM is/are correct?

• 1. It has components that include decentralised grid-connected renewable plants and solar pumps.
• 2. MNRE notes a target of adding 34,800 MW by March 2026 under PM-KUSUM.
• (A) 1 only
• (B) 2 only
• (C) Both 1 and 2
• (D) Neither 1 nor 2

Answer: (C)

Explanation: MNRE describes PM-KUSUM with multiple components (A, B, C) including decentralized grid-connected plants and solar pumps, and mentions a target of 34,800 MW by March 2026.

MCQ 4

Question: The primary role of SECI in many renewable tenders is best described as:

• (A) Regulator that sets electricity tariffs for states
• (B) Power procurement intermediary signing PPAs with developers and PSAs with DISCOMs
• (C) Manufacturer of solar PV modules
• (D) Agency that only builds hydropower projects

Answer: (B)

Explanation: SECI acts as an intermediary by signing PPAs with developers and PSAs with DISCOMs, supporting renewable procurement at scale and improving bankability.

MCQ 5

Question: Which pair is correctly matched with the state that leads India in installed wind capacity (as on 31.12.2025)?

• (A) Gujarat — highest wind capacity
• (B) Rajasthan — highest wind capacity
• (C) Kerala — highest wind capacity
• (D) Bihar — highest wind capacity

Answer: (A)

Explanation: MNRE state-wise data shows Gujarat has the highest installed wind capacity (~14.82 GW), followed by Tamil Nadu, Karnataka, Maharashtra, and Rajasthan.

MCQ 6

Question: According to IRENA (end-2024), which renewable source has the largest share of global renewable power capacity?

• (A) Solar
• (B) Wind
• (C) Bioenergy
• (D) Geothermal

Answer: (A)

Explanation: IRENA highlights show that at the end of 2024, global renewable power capacity was 4,448 GW and solar had the largest share with 1,865 GW, higher than wind (1,133 GW) and hydropower (1,283 GW).

MCQ 7

Question: Which of the following is the most appropriate context for "pumped storage hydropower"?

• (A) A method of drip irrigation
• (B) Long-duration energy storage for grid balancing
• (C) A method of producing ethanol
• (D) A policy to reduce GST on solar panels

Answer: (B)

Explanation: Pumped storage is a hydro-based storage system used to store electricity by pumping water to a higher reservoir and generating power later during peak demand. It is widely discussed as long-duration energy storage, including in UPSC context.

MCQ 8

Question: Which of the following statements about the National Green Hydrogen Mission is correct?

• (A) It targets 5 MMT per annum by 2040 and has an outlay of ₹5,000 crore
• (B) It targets 5 MMT per annum by 2030 and has an initial outlay of ₹19,744 crore
• (C) It targets only blue hydrogen and excludes electrolysis
• (D) It is implemented only by state governments without MNRE involvement

Answer: (B)

Explanation: MNRE notes the National Green Hydrogen Mission has an initial outlay of ₹19,744 crore and targets 5 MMT green hydrogen production capacity per annum by 2030.

MCQ 9

Question: Which statement best captures the latest reported ethanol blending progress in ESY 2024–25 (as per government release)?

• (A) Blending stayed below 5% in July 2025
• (B) Blending was 10% as on 31.07.2025
• (C) Blending averaged about 19.05% as on 31.07.2025 and reached about 19.93% in July 2025
• (D) Ethanol blending was stopped in 2025 due to vehicle issues

Answer: (C)

Explanation: A PIB note reported that during ESY 2024–25, average blending reached 19.05% as on 31.07.2025, and 19.93% in July 2025.

MCQ 10

Question: Which of the following correctly explains why rooftop solar is important for India's energy transition?

• (A) It always produces electricity at night
• (B) It produces electricity close to consumers, reduces transmission losses, and supports decentralised clean power
• (C) It can only be installed in deserts
• (D) It reduces the need for any grid planning

Answer: (B)

Explanation: Rooftop solar is decentralised generation. It produces power near consumption, can reduce losses, and helps households and small businesses participate in clean energy. MNRE's rooftop programme targets large-scale rooftop capacity expansion.

17) How to Write a Strong Mains Answer (Ready Framework)

Introduction (2–3 lines): Define renewables and connect to India's goals (energy security + climate + jobs). Mention 500 GW by 2030 and net zero 2070.

Body (structured):

• Solar: largest capacity; solar parks (Bhadla, Pavagada); rooftop; PM-KUSUM; issues of intermittency and land.
• Wind: corridor states (Gujarat, Tamil Nadu, Maharashtra); transmission and policy stability; repowering.
• Hydro: balancing and peaking; small vs large classification; pumped storage for long-duration storage; ecological concerns.
• Biomass: dispatchable renewable; SATAT; ethanol blending progress; sustainability challenges.
• Green Hydrogen: industrial decarbonisation and storage; 5 MMT by 2030; ₹19,744 crore outlay.

Conclusion: Stress that renewables growth must be paired with grid upgrades, storage, finance reforms, and stable procurement to convert capacity into reliable clean electricity.