Harnessing Hydrogen

Tokyo 2020 Olympics was all set to unravel the  unique  achievements of Japan  in harnessing hydrogen energy. In fact the tagline of the Tokyo Olympics was  to be Hydrogen Olympics.  Japan was ready with its fleet of hydrogen powered vehicles, hydrogen refueling stations and   hydrogen powered athletes' villages. But unfortunately the event had to be called off due to the pandemic. But Japan is not disappointed. Tokyo Olympics was just one of the milestones in  Japan's roadmap  to  green eneergy.  Japan is bent upon  erasing its carbon footprints as much as possible  by  2050.  To reach  this final destination Japanese  academic and industrial research institutions  are working overtime , in close collaboration.  

Concept of a fuel cell

The energy content in 1 kg hydrogen is almost equivalent to 1 gallon(~ 2.8kg) of  gasoline. The concept of hydrogen fuel cells was demonstrated way back in 1932 and since then has been  tapped in  limited edition applications.  In its simplest form an hydrogen fuel cell consists of anode and cathode separated by an electrolyte. Hydrogen is introduced at the anode and air/oxygen at the cathode. At the anode a catalyst  splits  hydrogen atoms  into protons  and electrons. The protons move through the electrolyte  towards cathode, combine with oxygen and form water.  Electrons flow through the external circuit generating an electric current.   Simple though it is,  there are several complex technical challenges to overcome to make the process commercially feasible. Challenges begin   from the  primary production stage to  storage, transportation, delivery and ultimate use. 

Hydrogen is abundant in nature but is always  in chemically combined form such as in water or in hydrocarbons. Hence it is necessary to have cost effective processes to strip hydrogen free. Then comes the storage needs. While for on-site applications, perhaps hydrogen can be stored in gaseous form, for long distance distributed applications  appropriately designed network of  gas pipelines is necessary. That calls for huge investments in infrastructure development.  Storage and distribution as  liquid  hydrogen is another possibility but requires cooling the gas to  -263 degC making it  an energy intensive, expensive process.  Fixing hydrogen gas as ammonia  is often preferred because  ammonia is easy to liquify and transport, and later hydrogen can be reclaimed through   catalytic cracking  of ammonia.  

Chiyoda Corporation  believes in  Energy and Environment in Harmony. Scientists and Technologists at  Chiyoda have come up with a more attractive alternative.  They  have perfected the technology of reversibly  hydrogenating toluene to methyl cyclohexane (MCH) using  platinum nanoparticles as catalysts. The advantage with MCH is that the existing petroleum refinery set up and associated storage/distribution network system could be used as such with minimal modification. That spells a huge saving.  In April 2020 Chiyoda  joined hands with  Mitsubishi Corporation, Mitsui & Co. Ltd. and NYK Shipping Line  and   transported MCH produced at  Darussalam, Brunei  to Kawasaki refineries in Japan. In fact  Kawasaki  is   involved in all 4 stages: production, storage, transportation and utilisation. While Mitsubishi  is  experimenting with  hydrogen gas turbines,  ENEOS, the mammoth energy company will be setting up hydrogen refilling stations for automobiles.  Japan is dead serious about  its Mission Hydrogen. It has even set a target price  of  US$ 2.0 per kg by 2050.   

Tailpiece:

In the meanwhile hydrogen is getting color-coded  depending upon how it is produced. 

   

Grey Hydrogen:      Natural gas is split into hydrogen and CO2   .  Hydrogen is collected and                                          stored, but CO2 is let out into the atmosphere.  This is the current process.

Blue Hydrogen:       Process is the same as for Grey Hydrogen but CO2 is  not let out into the                                      atmosphere but fixed in appropriate manner.

Green Hydrogen:     Hydrogen is produced by electrolysis of water using energy from a                                                combination of  renewable resources such as  wind and solar 

Pink Hydrogen:        Electrolysis of water using  nuclear power.

Yellow Hydrogen:     Electrolysis of water using exclusively  solar power.

REFERENCES:

1. Focal point : Hydrogen Energy in Japan : Nature 25th March 2021

2. Alternate Fuels Data Centre

3. Transitioning to hydrogen

4. Australia's pathway to $2 per kg hydrogen

5. The hydrogen color spectrum