S&T Decoder: The Future is Green

Phase 1: The Foundation (Renewable Sources)

Energy that never runs out. As long as the Sun shines and the Wind blows, we have power.

1. Solar Energy

• Photovoltaic (PV) Cells: Convert sunlight directly into electricity using Silicon.
• India's Goal: Target of 500 GW non-fossil fuel capacity by 2030 (COP26).

2. Other Clean Sources

• Wind Energy: India is the 4th largest in wind power capacity.
• Green Hydrogen: Produced by electrolysis of water using renewable energy. Zero carbon emissions.
• Fuel Cells: Generate electricity via chemical reaction (Hydrogen + Oxygen $ightarrow$ Water + Power).

Phase 2: The Core Logic (Nano & Robotics)

1. Nanotechnology (Thinking Small)

• Scale: 1 to 100 nanometers ($10^{-9}$ meters).
• Applications: Targeted drug delivery, lighter aircraft, water purification.
• Carbon Nanotubes: 100 times stronger than steel but 6 times lighter.

2. Robotics

• Components: Sensors (Senses), Controller (Brain), Actuators (Muscles).
• Isaac Asimov's Laws: Safety rules for robots to protect humans.

Phase 3: The Exam Edge (Sustainable Living)

1. Green Buildings

• Designed to use minimum water, energy, and resources. GRIHA and LEED are certification systems.

2. Solid Waste Management

• The 3 R's: Reduce, Reuse, Recycle.
• Biogas: Produced from organic waste (Anaerobic digestion). Mainly Methane ($CH_4$).

[!TIP]
International Solar Alliance (ISA): Jointly launched by India and France to promote solar energy in "Sun-rich" countries.