Geoengineering & Carbon Capture Technologies | Science & Technology for UPSC CSE PDF Download

Introduction

Climate change, driven by GHG emissions, has warmed the planet by ~1.3°C (2024) above pre-industrial levels, necessitating urgent mitigation. Geoengineering offers potential solutions to cool the planet, while carbon capture technologies reduce emissions from coal, cement, and other industries. India, with its 1.4 billion population, 7,516 km coastline, and monsoon-dependent agriculture, faces severe climate risks (e.g., 10% of global cyclones). The Intergovernmental Panel on Climate Change (IPCC) AR6 (2021–2023) emphasizes CCS/CCU and cautious geoengineering to limit warming to 1.5°C. India’s efforts, supported by the International Solar Alliance (ISA) and Coalition for Disaster Resilient Infrastructure (CDRI), align with SDG 13 (Climate Action). Recent developments, like NTPC’s CCS pilot (2024) and global geoengineering trials, underscore their growing relevance. This topic is critical for understanding India’s climate strategy and global innovation.

Geoengineering: Principles and Methods

Geoengineering involves large-scale interventions to counteract climate change by reflecting sunlight or removing CO2. It is categorized into two approaches:

1. Solar Radiation Management (SRM)

• Principle: Reflects sunlight to reduce global temperatures, without addressing CO2 levels.

• Methods:

  • Stratospheric Aerosol Injection (SAI): Injecting sulfur aerosols into the stratosphere to reflect sunlight (mimics volcanic cooling, e.g., 1991 Mount Pinatubo eruption reduced temperatures by 0.5°C).

  • Marine Cloud Brightening: Spraying seawater to whiten clouds, enhancing reflectivity.

  • Surface Albedo Enhancement: Painting roofs white or deploying reflective materials in deserts.

• Advantages: Rapid cooling (within months); relatively low cost (~$10 billion/year globally).

• Risks: Does not reduce CO2; potential side effects (e.g., altered monsoons, acid rain); “termination shock” if stopped abruptly.

2. Carbon Dioxide Removal (CDR)

• Principle: Removes CO2 from the atmosphere for long-term storage or use.

• Methods:

  • Afforestation/Reforestation: Planting trees to absorb CO2 (e.g., India’s Green India Mission targets 6 million hectares by 2030).

  • Bioenergy with Carbon Capture and Storage (BECCS): Burning biomass and capturing CO2 for storage.

  • Direct Air Capture (DAC): Using chemical scrubbers to extract CO2 from air.

  • Ocean Fertilization: Adding iron to oceans to boost phytoplankton CO2 absorption.

  • Enhanced Weathering: Spreading minerals (e.g., basalt) to absorb CO2 via chemical reactions.

• Advantages: Addresses root cause (CO2); supports net-zero goals.

• Risks: High costs (DAC: $600/ton CO2); land/ocean ecosystem impacts; slow scalability.

India’s Geoengineering Efforts

• Limited Engagement: India focuses on CDR (e.g., afforestation) over SRM due to monsoon risks. The Green India Mission has afforested 2 million hectares (2025).

• Research: Indian Institute of Science (IISc) and IIT Delhi study DAC and enhanced weathering; 2025 pilot in Gujarat tests basalt weathering.

• Policy Caution: India opposes SRM at UNFCCC forums, citing risks to monsoons (70% of agriculture dependent).

Carbon Capture Technologies: CCS and CCU

1. Carbon Capture and Storage (CCS)

• Principle: Captures CO2 from point sources (e.g., power plants, cement factories) and stores it underground in geological formations.

• Process:

  • Capture: Post-combustion (amine scrubbing), pre-combustion (gasification), or oxy-fuel combustion.

  • Transport: Pipelines or ships move CO2 to storage sites.

  • Storage: Injection into deep saline aquifers, depleted oil/gas fields, or basalt formations (1–2 km underground).

• Capacity: Global CCS captures ~45 MtCO2/year (2024); IPCC AR6 estimates 1–10 GtCO2/year needed by 2050.

• India’s Efforts:

  • NTPC’s 10 MW CCS pilot at Vindhyachal (2024) captures 20,000 tCO2/year.

  • ONGC explores storage in Gujarat’s Cambay Basin; 2025 feasibility study targets 1 MtCO2/year by 2030.

  • Coal-based plants (50% of India’s energy mix) prioritized for CCS retrofitting.

2. Carbon Capture and Utilisation (CCU)

• Principle: Captures CO2 and converts it into products like fuels, chemicals, or building materials.

• Applications:

  • Fuels: Synthetic methane, methanol (e.g., IndianOil’s 2025 methanol pilot).

  • Chemicals: Urea, polymers (e.g., Reliance’s CO2-to-plastics pilot, 2024).

  • Construction: Carbonated concrete, aggregates (e.g., CarbonCure technology tested in India, 2025).

• India’s Efforts:

  • Carbon Clean Solutions: Indian startup’s CCU plant in Tuticorin (2024) converts CO2 into soda ash.

  • Dalmia Cement: 2025 pilot converts CO2 into building materials, targeting 0.5 MtCO2/year by 2030.

  • Green Hydrogen Synergy: CCU produces synthetic fuels using green hydrogen (National Green Hydrogen Mission, 5 MMT by 2030).

Recent Developments (2024-2025)

• Budget 2025-26: ₹10,000 crore for CCS/CCU pilots; ₹1.97 lakh crore for clean energy, including CCU scaling.

• India-US Collaboration: 2025 agreement under iCET for CCUS technology transfer; pilot at NTPC Dadri.

• Private Sector: Reliance, Adani invest ₹5,000 crore in CCU (2024–25); focus on CO2-to-fuels.

• ISRO Support: Satellites (e.g., INSAT-3D) monitor CO2 emissions, aiding CCS site selection.

India’s Role and Policy Framework

Climate Vulnerability

• Emissions: 2.9 GtCO2e (7% of global total, 2024); per capita 2.1 tCO2e (vs. global 4.7 tCO2e).

• Risks: Cyclones (10% of global total), floods (₹1 lakh crore annual loss), Himalayan glacier retreat (30% by 2050), and agricultural yield declines (10–15% for rice by 2050).

Policy Integration

• NAPCC (2008): National Mission for Enhanced Energy Efficiency promotes CCS in industries; Green India Mission supports CDR via afforestation.

• National Green Hydrogen Mission (2023): Synergizes with CCU for synthetic fuel production.

• National Carbon Market: Launched 2025, incentivizes CCS/CCU via carbon credits (₹50/ton CO2).

• ISA and CDRI: India leads global efforts, sharing CCU tech with Global South.

Key Initiatives

• NTPC and ONGC Pilots: CCS at coal plants; storage in Gujarat’s geological formations.

• Private Sector: Startups like Carbon Clean and established firms (Tata, Reliance) drive CCU innovation.

• Research: IITs, IISc lead DAC and weathering studies; 2025 budget allocates ₹2,000 crore for R&D.

• International Commitments: India’s NDCs (2023 update) target 50% non-fossil energy by 2030, with CCS/CCU as key enablers.

Global Context and Comparisons

Global Trends

• CCS Scale: 45 MtCO2/year captured (2024); US leads with 20 projects (15 MtCO2). Norway’s Longship project stores 1.5 MtCO2/year.

• CCU Growth: Global market $4 billion (2024), projected $15 billion by 2030. China leads in CO2-to-methanol.

• Geoengineering: US (Harvard’s Solar Geoengineering Research) and China test SAI; DAC plants operational in Iceland (Climeworks, 4,000 tCO2/year).

• IPCC AR6 (2021–2023): Recommends 1–10 GtCO2/year CCS by 2050; cautious on SRM due to risks.

Comparisons

• US: $50 billion in CCS/CCU via 45Q tax credits; leads DAC with 10 plants. India lags in scale but excels in low-cost CCU (e.g., Tuticorin plant).

• China: 10 MtCO2/year CCS; 50% of global CCU capacity. India’s thorium and hydrogen synergies offer unique potential.

• EU: 5 MtCO2/year CCS; focus on DAC and BECCS. India’s afforestation scale (2 million hectares) surpasses EU efforts.

• India’s Edge: Low-cost innovation (CCU at ₹100/ton vs. $200 globally); vast thorium reserves for clean energy integration.

Challenges, Future Prospects, and Significance

Challenges

• High Costs: CCS ($50–100/ton CO2), DAC ($600/ton) are expensive; India’s budget constraints limit scaling.

• Infrastructure: Lack of CO2 pipelines and storage sites (only 2 identified in India).

• SRM Risks: Potential monsoon disruption; India opposes SRM at COP30 (2025).

• Public Perception: Resistance to CCS storage (e.g., Gujarat communities fear leaks).

• Technology Access: Dependence on foreign DAC/CCS tech; limited domestic R&D capacity.

Future Prospects

• CCS/CCU Scale-Up: India targets 10 MtCO2/year capture by 2030; ₹20,000 crore investment planned.

• DAC Development: Pilot plants by 2030; IISc targets $100/ton CO2 by 2035.

• Geoengineering Research: Limited SRM trials; CDR focus via afforestation, BECCS by 2040.

• Private Sector: Reliance, Adani to invest ₹10,000 crore in CCU by 2030.

• Global Leadership: India to share low-cost CCU tech via ISA, CDRI by 2030.

Significance for India

• Climate Resilience: Mitigates impacts on 1.4 billion (e.g., coastal flooding, agricultural losses).

• Energy Security: CCS enables coal use during transition; CCU supports green hydrogen economy.

• Economic Growth: CCU market adds $50 billion to GDP by 2035; aligns with $1 trillion clean energy goal.

• Global Standing: Leadership in low-cost CCU and ISA strengthens India’s UNFCCC role.
  

Geoengineering and carbon capture technologies offer critical tools for India to combat climate change while sustaining economic growth. CCS and CCU address industrial emissions, with pilots like NTPC’s Vindhyachal plant paving the way for scalability. Geoengineering, particularly CDR via afforestation, aligns with India’s NAPCC, though SRM remains contentious. Recent developments, like the 2025-26 budget and India-US collaborations, signal robust progress. By overcoming challenges like cost and infrastructure, India can leverage these technologies to meet its net-zero and renewable energy goals, cementing its role as a global climate leader. This topic is essential for UPSC aspirants, highlighting India’s climate innovation and international influence.