Why the World Needs Better Green Technologies

Costs of Green Hydrogen 

• Green Hydrogen: Produced by electrolysis of water using electricity from renewable sources (e.g., solar, wind).

• Electrolysis: Process of splitting water (H₂O) into hydrogen (H₂) and oxygen (O₂) using electric current.

Environmental Advantage

• No greenhouse gas (GHG) emissions when green hydrogen is combusted.

• Considered a clean energy carrier for decarbonising sectors like steel, transport, and chemicals.

Cost and Energy Concerns

• High Energy Input: Current electrolysis technologies consume more energy than the usable energy value of hydrogen produced.

• Inefficient Silicon Photovoltaics: Widely used solar panels (silicon-based) are less efficient compared to other emerging solar technologies.

Storage and Transportation Challenges

• Low Density of Hydrogen:

  • Leads to leakage.

  • Difficult to store and transport safely and economically.

• Requires high-pressure tanks or liquefaction at −253°C, which adds to costs.

Use of Carriers: Ammonia & Methanol

• Green Ammonia (NH₃) and Green Methanol (CH₃OH) used as hydrogen carriers for easier transport.

• Hydrogen is extracted from them at destination.

But:

• Conversion into ammonia/methanol and reconversion back to hydrogen also requires significant energy.

• Additional steps reduce overall efficiency.

Net Energy Chain and Efficiency Loss

• Multiple steps lead to cumulative energy losses:

  1. Solar energy (from silicon PV)

  2. Electrolysis

  3. Conversion to carrier (NH₃/CH₃OH)

  4. Transport and Storage

  5. Re-conversion or usage

• Each stage adds to costs and reduces the ‘greenness’.

CO₂ Recycling and Artificial Photosynthesis (APS):

• CO₂ Recycling: Using carbon dioxide as a raw material to synthesize fuels like green methanol or green ammonia, instead of releasing it into the atmosphere.

• Artificial Photosynthesis (APS): Mimics natural photosynthesis by converting sunlight, water, and carbon dioxide into energy-rich compounds, mainly fuels.

Potential Applications:

• Green Methanol (CH₃OH) and Green Ammonia (NH₃) can be synthesized from:

  • Water (H₂O)

  • Sunlight (solar energy)

  • CO₂ (from air or industrial emissions)

  • Nitrogen (from air)

Advantages:

• Reduces greenhouse gases by capturing CO₂.

• Promotes circular carbon economy.

• Reduces dependency on fossil fuels.

• Produces easily storable and transportable fuels.

Challenges:

• APS is still in experimental/laboratory stage.

• High energy inputs required.

• Low efficiency and cost-effectiveness compared to conventional fuels.

• Needs significant R&D investment for commercial viability.

Renewable Fuels of Non-Biological Origin (RFNBO):

• RFNBOs are fuels produced without using biomass, instead using renewable electricity and inorganic feedstocks (e.g., water, CO₂, nitrogen).

• Example fuels: green hydrogen, green ammonia, synthetic methane, e-fuels.

Status:

• Europe is leading RFNBO development and regulations (under EU Renewable Energy Directive).

• India is in early stages but has strategic interest due to high energy import dependence (~85%).

Importance for India:

• Reduces energy imports and improves energy security.

• Supports net-zero emissions targets by 2070.

• Helps mitigate climate-related and geopolitical risks in energy supply.

Policy Suggestion:

• Increased investment in research and innovation.

• Public-Private Partnerships (PPP) in clean energy R&D.

• Strong regulatory framework and global collaboration.

Insights:

• Diverse technologies, not just a few like green hydrogen or solar PV, are necessary to meet future energy and climate goals.

• Energy efficiency and practicality are critical for any green fuel.

• Technologies like APS and RFNBO can revolutionize the energy sector, but require:

  • Long-term R&D

  • Regulatory support

  • Industrial scalability