Renewable & Alternative Energy

Exploring India's Journey Towards a Sustainable Energy Future and Climate Resilience.

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Understanding Renewable & Alternative Energy

Renewable Energy

Energy sources that are naturally replenished on a human timescale. They are sustainable and generally have a much lower environmental impact (especially lower GHG emissions) compared to fossil fuels.

Examples:

  • Solar energy
  • Wind energy
  • Hydropower
  • Biomass energy
  • Geothermal energy
  • Tidal energy

Alternative Energy

A broader term including renewables and other non-conventional fossil fuel alternatives, focusing on low-carbon options for climate mitigation.

Includes renewables plus:

  • Nuclear energy
  • Some forms of biofuels (from non-renewable biomass)
  • Novel energy technologies

Why Are They Important?

Climate Change Mitigation

Reduce GHG emissions from the energy sector.

Energy Security

Decrease reliance on imported fossil fuels, diversify supply.

Environmental Protection

Lessen air and water pollution from fossil fuels.

Economic Benefits

Create green jobs, foster innovation, lower long-term energy costs.

Energy Access

Power remote and off-grid areas with decentralized systems.

Sustainable Development

Achieve SDGs, especially SDG 7 (Clean Energy) & SDG 13 (Climate Action).

Major Renewable Energy Sources in India

Solar Energy

Converts sunlight into electricity (Photovoltaic - PV) or thermal energy (Concentrated Solar Power - CSP). India has vast potential due to its tropical location (avg. 300 sunny days, 4-7 kWh/m²/day insolation).

Technologies:

  • Solar PV: Crystalline silicon (mono, poly), thin-film. Used for grid-power, rooftops, off-grid applications.
  • Solar Thermal: Low-temp (water heaters, cookers), CSP (electricity generation).

Potential in India:

Vast Potential (est. 748 GW)

Estimated potential indicates significant capacity.

Key Initiatives in India
  • Jawaharlal Nehru National Solar Mission (JNNSM) (2010): Catalyzed solar deployment.
  • Significant capacity addition targets.
  • Solar Parks & Ultra Mega Solar Power Projects: Large-scale grid-connected plants.
  • PM-KUSUM: Solar for agriculture (pumps, grid-connected).
  • Rooftop Solar Programme: Incentives for residential, commercial, industrial rooftops.
  • International Solar Alliance (ISA): Co-founded by India, promoting global solar energy.
Advantages
  • Abundant resource
  • Decreasing PV costs
  • Modular deployment
  • Low maintenance (PV)
  • Clean during operation
Challenges
  • Intermittency (sunlight dependent)
  • Land requirement for large plants
  • Energy storage costs (batteries)
  • PV cell efficiency & dust
  • Grid integration issues

Wind Energy

Converts kinetic energy of wind into electricity using turbines. Significant potential in coastal states (TN, GJ, MH, KA, RJ, AP, MP). HAWTs are common; offshore potential emerging.

Key Initiatives & Policies
  • Feed-in Tariffs (historically) & Competitive Bidding (currently)
  • Generation-Based Incentives
  • Renewable Purchase Obligations (RPOs)
  • Development of Wind Parks
  • Focus on Offshore Wind Energy Potential
Advantages
  • Clean energy source
  • No operational emissions
  • Mature technology
  • Land co-use possible
Challenges
  • Intermittency (wind dependent)
  • Visual impact & noise
  • Bird/bat impact (siting)
  • Land acquisition
  • Grid integration/stability

Hydropower

Uses energy of flowing/falling water. Considerable potential in Himalayan region & Western Ghats. Types: Large (>25MW), Small (≤25MW), Run-of-river, Storage (dam-based).

Advantages
  • Renewable, no direct operational GHG emissions
  • Dispatchable power (especially storage)
  • Long operational life
  • Ancillary benefits (flood control, irrigation)
Challenges
  • Environmental impacts (land submergence, biodiversity)
  • Social impacts (displacement)
  • High upfront costs, long gestation
  • Geological risks, climate change impacts on water flow
  • Methane from reservoirs (tropical areas)

Biomass Energy

Energy from organic matter (plants/animals). Sources: Agri/forest residues, energy crops, manure, organic waste. Technologies: Direct combustion, gasification, anaerobic digestion, biofuels.

Biofuels Spotlight
  • Ethanol: From sugars/starches (sugarcane, corn). Blended with petrol (EBP Programme).
  • Biodiesel: From vegetable oils (Jatropha, Pongamia), animal fats. Blended with diesel.
  • Advanced Biofuels (2nd/3rd Gen): From non-food feedstocks (lignocellulosic biomass, algae) to reduce food vs. fuel debate.
Advantages
  • Renewable (if sustainably sourced)
  • Potentially carbon neutral
  • Utilizes waste materials
  • Rural employment, biofuels for existing engines
Challenges
  • Sustainability of supply (deforestation, food competition)
  • Land use for energy crops
  • Combustion emissions (PM, NOx)
  • Conversion efficiency/cost, logistics
  • Food vs. Fuel debate (1st gen biofuels)

Geothermal & Ocean Energy

Geothermal Energy

Uses heat from Earth's interior. Potential in Puga Valley (Ladakh), Tattapani (Chhattisgarh), etc.

Advantages: Reliable, small land footprint, low GHG emissions.

Challenges: High upfront costs, site-specific, limited commercial deployment in India.

Ocean Energy

Energy from oceans (Tidal, Wave, OTEC, Salinity Gradient). India has potential but still in R&D/pilot stages.

Advantages: Vast potential, predictable (tidal).

Challenges: High costs, tech immaturity, harsh marine environment, marine ecosystem impacts.

Alternative Low-Carbon Source: Nuclear Energy

Nuclear Energy in India

Uses heat from nuclear fission (Uranium) for electricity. India has an established program (PHWRs, BWRs) and developing FBRs (three-stage program).

Advantages
  • Very low GHG emissions (operation)
  • High power output (high energy density)
  • Provides baseload power (reliable)
  • Reduces fossil fuel import dependence
Challenges & Concerns
  • Safety (accident risk)
  • Radioactive waste management
  • Nuclear proliferation concerns
  • High capital costs, long construction
  • Public perception & acceptance
  • Fuel availability (Uranium constraints)

Emerging Energy Technologies

Green Hydrogen

Hydrogen from electrolysis using renewable electricity (zero-emission fuel). Uses: transport, industry, power, storage.

National Hydrogen Mission:

Aims for India to be a global hub for green hydrogen production/export.

Challenges:

High electrolysis cost, energy losses, storage/transport, infrastructure.

Fuel Cells

Electrochemical devices converting chemical energy (hydrogen, natural gas, methanol) directly to electricity with high efficiency, low emissions.

Advanced Energy Storage

Crucial for grid stability with intermittent renewables.

  • Batteries (Li-ion, flow, solid-state)
  • Pumped hydro storage
  • Compressed air energy storage (CAES)
  • Hydrogen storage

Key Government Initiatives & Policies

MNRE

Ministry of New and Renewable Energy - Nodal agency.

Ambitious Targets

e.g., 500 GW non-fossil fuel capacity by 2030 (Panchamrit).

Solar Missions

National Solar Mission, PM-KUSUM, Rooftop Solar schemes.

Wind Policies

Competitive bidding, National Offshore Wind Energy Policy.

Biofuel Policy

National Policy on Biofuels.

Hydrogen Mission

National Hydrogen Mission for green hydrogen.

RPOs

Renewable Purchase Obligations for Discoms & consumers.

Financial Incentives

Subsidies, tax benefits, VGF, concessional finance.

Green Energy Corridors

Transmission infra for RE power evacuation.

ISTS Charge Waiver

For inter-state transmission of solar/wind power.

UPSC Examination Relevance

Prelims Focus

  • Types of RE sources (principles, potential, pros/cons).
  • Key technologies (PV, CSP, turbines, biofuels).
  • Major government schemes (JNNSM, PM-KUSUM, NBM, ISA, RPOs).
  • Nuclear energy basics, India's program.
  • Green Hydrogen concepts.

Mains Focus (GS Paper III)

  • India's RE potential, initiatives, and challenges.
  • Role of solar energy in energy security & climate mitigation.
  • Green Hydrogen: potential and National Hydrogen Mission.
  • Critical analysis of nuclear energy.
  • Linkages: RE, energy transition, economy, SDGs.

Related Previous Year Questions (PYQs)

Prelims Example:

"With reference to 'Indian Renewable Energy Development Agency Limited (IREDA)', which of the following statements is/are correct?" (UPSC Prelims 2015)

Mains Example:

"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?" (UPSC Mains 2022, GS Paper III)