Detailed Explanation:

Answer: Option 3 — All three

Green hydrogen, produced from renewable energy sources through electrolysis, is a versatile clean fuel that can be utilized in multiple ways. All three statements regarding its applications are correct.

✅ Statement 1 – Correct: Green hydrogen can be used directly as a fuel in modified internal combustion engines, replacing conventional fossil fuels.
✅ Statement 2 – Correct: Green hydrogen can be blended with natural gas (up to 20% in existing pipelines) and used for heating, power generation, and industrial applications.
✅ Statement 3 – Correct: Green hydrogen is used in hydrogen fuel cells to generate electricity for running electric vehicles, offering zero-emission transportation.

📝 Short Notes: Green Hydrogen

• Definition: Hydrogen produced through electrolysis of water using renewable energy sources (solar, wind, hydro), resulting in zero carbon emissions.
• Production Method: Water (H₂O) is split into hydrogen (H₂) and oxygen (O₂) using electricity from renewable sources in an electrolyzer.
• Color Coding: Green (renewable energy), Grey (fossil fuels without carbon capture), Blue (fossil fuels with carbon capture), Brown/Black (coal).
• Applications: Transportation (fuel cell vehicles), industrial processes (steel, ammonia production), energy storage, power generation, and heating.
• India's Initiatives: National Green Hydrogen Mission (2023) targeting 5 MMT annual production by 2030; focus on making India a global hub for green hydrogen production and export.
• Advantages: Zero emissions at point of use, high energy density, long-term storage capability, and versatile applications across sectors.
• Challenges: High production costs, energy-intensive electrolysis process, storage and transportation infrastructure requirements, and need for renewable energy scale-up.