UPSC Mains Previous Year Questions 2025: GS3 Science & Technology

Q1: The fusion energy programme in India has steadily evolved over the past few decades. Mention India's contributions to the international fusion energy project International Thermonuclear Experimental Reactor (ITER). What will be the implications of the success of this project for the future of global energy? (150 words)
Ans:
India's fusion program, via IPR and SST-1 tokamak, has advanced since 1980s, joining ITER in 2005 with 9.1% contribution.

India's Contributions to ITER:

1. Cryostat: World's largest stainless-steel vacuum vessel, fabricated and delivered.
2. Cooling systems: Cryo-distribution lines and in-wall shielding.
3. Diagnostics: Tools for plasma measurement.
4. R&D: Superconducting magnets and tritium breeding tech.

Implications of Success:

1. Limitless Clean Energy: Fusion provides safe, zero-emission power, reducing fossil dependence.
2. Energy Security: Fuels like deuterium abundant, ending import vulnerabilities.
3. Climate Mitigation: No CO₂, aiding 1.5°C goal.
4. Economic Transformation: New industries, jobs; DEMO reactors by 2050.

ITER's success will revolutionize global energy, fostering sustainable development.

Q2: How can India achieve energy independence through clean technology by 2047? How can biotechnology can play a crucial role in this endeavour? (150 words)
Ans:
India aims for energy independence by 2047 via clean tech, targeting 500 GW non-fossil capacity and net-zero by 2070, reducing imports (85% oil).
Achieving Independence:

1. Scale renewables: Solar/wind to 1 TW, with green hydrogen hubs.
2. Electrify transport: Aim for 30% EV penetration in vehicle sales by 2030, with higher targets for two-wheelers (80%) and commercial vehicles (70%)"
3. Nuclear expansion: 100 GW capacity.
4. Efficiency measures: LED adoption, smart grids.

Role of Biotechnology:

1. Biofuels: Algae-based biodiesel, enzyme-enhanced ethanol from waste.
2. Bioenergy: GM crops for higher biomass yields.
3. Carbon sequestration: Microbial tech for soil CO₂ capture.
4. Sustainable agriculture: Reducing methane via biotech feeds.

Biotech integrates with clean tech for resilient, low-carbon energy, aligning with Amrit Kaal vision.

Q3: How does nanotechnology offer significant advancements in the field of agriculture? How can this technology help to uplift the socio-economic status of farmers? (250 words)
Ans:
Nanotechnology revolutionizes agriculture by enabling precision farming, addressing challenges like low productivity and climate variability in India, where agriculture employs 45% workforce but contributes 18% GDP. Nano-tools enhance efficiency, reducing input costs.

Advancements in Agriculture:

1. Nano-Fertilizers and Pesticides: Controlled release (e.g., nano-urea) improves nutrient uptake by 80%, minimizing leaching and pollution.
2. Precision Monitoring: Nanosensors detect soil moisture, pH, pathogens in real-time, enabling data-driven decisions via IoT.
3. Crop Protection: Nano-encapsulated herbicides target weeds, reducing chemical use by 50%; nano-coatings extend shelf life.
4. Genetic Enhancement: Nano-delivery systems for genes/seeds boost drought-resistant varieties, increasing yields.
5. Water Management: Nano-membranes purify irrigation water; hydrogels retain soil moisture in arid areas.

Uplifting Socio-Economic Status of Farmers:

1. Increased Productivity and Income: Higher yields (20-30% via nano-inputs) raise incomes; reduced losses from pests enhance market value.
2. Cost Reduction: Lower agrochemical needs cut expenses by 40%; affordable nano-kits empower smallholders.
3. Sustainable Practices: Eco-friendly methods preserve soil health, ensuring long-term viability; access to markets via quality produce.
4. Employment and Skills: Nano-agri creates jobs in rural tech; training programs build digital literacy.
5. Resilience to Climate Change: Adaptive tech mitigates risks, stabilizing earnings; government schemes like Nano Mission integrate subsidies.

By bridging yield gaps and promoting inclusivity, nanotechnology can transform farmers into agri-entrepreneurs, aligning with SDGs for poverty alleviation and food security.

Q4: India aims to become a semiconductor manufacturing hub. What are the challenges faced by the semiconductor industry in India? Mention the salient features of the India Semiconductor Mission. (250 words)
Ans:
India's semiconductor push targets a $1 trillion digital economy by 2025, but the industry, valued at $27 billion (design-focused), faces hurdles in fabrication amid global shortages. With 20% global design talent, scaling manufacturing is key.

Challenges Faced:

1. High Capital Intensity: Fab setup costs $10-12 billion; long gestation (3-5 years) deters investors.
2. Infrastructure Deficits: Requires ultra-pure water (millions liters/day), stable power; seismic zones and logistics issues in sites like Gujarat.
3. Talent and Technology Gaps: Shortage of 300,000 skilled engineers; limited IP and advanced tech transfer from global leaders.
4. Supply Chain Dependencies: 100% imports for raw materials like silicon wafers; geopolitical risks (Taiwan dominance).
5. Regulatory and Execution Hurdles: Delays in approvals; competition from China, Vietnam with established ecosystems.

Salient Features of India Semiconductor Mission (ISM):

1. Financial Incentives: 50% fiscal support for fabs, ATMP, and design; $10 billion outlay.
2. Scheme Components: Production Linked Incentive (PLI) for design; support for compound semis and packaging.
3. Ecosystem Development: Partnerships for skill training (1 million workforce by 2030); R&D hubs like Semi-Conductor Laboratory upgrade.
4. Strategic Projects: Approved 10 units (e.g., Tata's Assam fab, Micron's Gujarat ATMP) worth $18 billion.
5. Global Integration: Alliances like US-India iCET for tech transfer; focus on self-reliance via Deep Tech Alliance ($1 billion fund).

ISM's holistic approach can overcome challenges, positioning India as a global hub by fostering innovation and jobs.