About green hydrogen

• Green hydrogen is defined as hydrogen produced by splitting water into hydrogen and oxygen using renewable electricity. 
• Green hydrogen could be a critical enabler of the global transition to sustainable energy and net zero emissions economies.

Other types of hydrogen

• Brown hydrogen is produced using coal where the emissions are released to the air.
• Grey hydrogen is produced from natural gas where the associated emissions are released to the air.
• Blue hydrogen is produced from natural gas, where the emissions are captured using carbon capture and storage.
• Turquoise hydrogen is made using a process called methane pyrolysis to produce hydrogen and solid carbon. As a result, there is no requirement for carbon capture and storage (CCS) and the carbon can even be used in other applications. Where the electricity driving the pyrolysis is renewable, the process is zero-carbon.

National Green Hydrogen Mission

• The National Green Hydrogen Mission was launched recently to make the country a production and export hub of green hydrogen.
• It is aimed at producing 5 MMT (million metric tonne) of green hydrogen per annum with an associated renewable energy capacity addition of about 125 GW (giga watt) by 2030.
• The Mission will have wide ranging benefits- 
  • Creation of export opportunities for Green Hydrogen and its derivatives; 
  • Decarbonisation of industrial, mobility and energy sectors; 
  • Reduction in dependence on imported fossil fuels and feedstock; 
  • Development of indigenous manufacturing capabilities; 
  • Creation of employment opportunities (Over 6 lakh jobs)
  • Development of cutting-edge technologies.  

Challenges associated with green hydrogen

• The challenges to produce and use green hydrogen are
• Electrolyser challenge
  • India to achieve its 2030 target, it would need 12 times the current global electrolyser production capacity. 
  • The factors that could hinder scaling up electrolyser manufacturing capability in India are
    • Negligible actual number of projects to manufacture electrolysers, 
    • Limited access to critical minerals such as nickel, platinum group metals and rare earth metals such as lanthanum, yttrium and zirconium which are concentrated in countries such as China, Democratic Republic of Congo (DRC), Australia, Indonesia, South Africa, Chile and Peru.
    • Limited processing capabilities in these minerals 
• Energy source challenge: As per current estimates a completely efficient electrolysis system would require 39 kWh of electricity to produce 1 kg of hydrogen.
  • Green hydrogen requires renewable energy as a source of electricity, however India has only achieved 119 GW of the 175 GW targeted capacity using solar, wind, bio-power and small hydro so far.
• End use challenge: Currently, most of the demand for hydrogen comes from the chemical industry to produce ammonia for fertilizers, followed by refining for hydrocracking and the desulphurisation of fuels. 
  • It can be a source of heat for industry, especially in sectors such as steel, cement and aluminum production. 
  • In the transport sector, it can be used as fuel for heavy duty vehicles, aviation and shipping. 
  • The conversion efficiency from one form of energy carrier to another in the end use application will determine the scale of green hydrogen’s applicability.
• Endogenous resources challenge: It has been estimated that the production of one kg of hydrogen by electrolysis requires around nine litres of water. 
  • Several parts of India are already severely water-stressed.
  • Solution to cater this additional demand such as desalination apart from increasing the physical footprint of the required infrastructure, it also add to competition for land use, impacts biodiversity and creates challenges and limitations in the location of electrolysers.  

How to address these challenges?

• India should set up large scale electrolyser manufacturing, secure geo-political partnerships for procurement of critical minerals and improve overall technical and economic viability of electrolysers year-over-year while competing with other global players.
• India should add close to 100 GW of overall renewable energy capacity per year over the next seven years and make available dispatch corridors and mechanisms.
• It is critical to establish safety standards for storage and transportation if green hydrogen has to be produced and stored in different forms for later use.
• The proposed green hydrogen hubs have to strike a fine balance between being renewable energy rich, water resource rich and being close to hydrogen demand (end-use) centers for them to be economically feasible. 

Conclusion

• The International Renewable Energy Agency (IRENA) estimates that hydrogen and its derivatives will account for 12 percent of global final energy consumption by 2050 with two-thirds coming from green hydrogen. 
• As India aims to produce green hydrogen in the range of Rs 100-150/kg by 2030 which is much below the currently global levelised cost of producing it. (Rs 250-650/kg).
• This would mean India will have to address all the challenges listed above as well as coordinate across multiple institutional bodies both public and private in record time. 

https://indianexpress.com/article/opinion/columns/indias-green-hydrogen-challenge-8435339/