The Indian Railways lately introduced {that a} hydrogen-powered prepare, developed at the Integral Coach Factory in Chennai, has efficiently accomplished all assessments. This is a welcome signal of progress for the National Green Hydrogen Mission, which goals to supply no less than 5 million metric tonnes of green hydrogen per 12 months by the 12 months 2030, a milestone on the option to attaining nationwide internet zero emissions by 2070.
The prepare will quickly be carrying passengers between Jind and Sonipat on an 89-km route in Haryana. This venture will depend on hydrogen produced in Jind by a 1-MW polymer electrolyte membrane electrolyser that produces 430 kg of hydrogen daily. The hydrogen will refill gas tanks on the prepare, the place gas cells will convert the hydrogen to electrical energy that runs the prepare’s electrical motors.
The precept is sort of easy. An electrolyser splits a water molecule into oxygen, protons, and electrons. In an electrochemical response at the destructive electrode (referred to as the anode), molecular oxygen is launched, and the electrons liberated are performed to the cathode by way of an exterior circuit. The polymer electrolyte membrane between the cathode and the anode is selective and solely permits protons to move by means of to the cathode, the place they unite with the electrons to kind hydrogen molecules. These rise as a gasoline and are collected, compressed, and saved. The membrane, sometimes a fluoropolymer comparable to Nafion (associated to Teflon) is a wonderful insulator, and electrons won’t move. The hydrogen and oxygen shaped are clearly separated.
In the locomotive, as in a hydrogen-powered vehicle, the above response is reversed in the hydrogen gas cell. Hydrogen is delivered to the anode, the place every molecule is catalytically break up into two protons and two electrons. The protons move by means of the membrane to the cathode, the place they meet oxygen in air and the electrons which can be introduced by means of an exterior circuit from the anode. Water is shaped. The electrons flowing by means of the exterior circuit represent the electrical present that powers the locomotive.
There is a key distinction between the chemical reactions in the gas cell and in the electrolyser. The chemistry between hydrogen and oxygen is spontaneous, a response ready to occur. Water, nevertheless, won’t break up into the two parts by itself. Electrical present have to be provided to offer the vitality for this electrochemical response.
To produce green hydrogen, the electrical energy for the electrolysers has to return from renewable sources, comparable to photo voltaic panels or wind generators. New sources of renewable vitality will likely be wanted to satisfy the objectives of the National Green Hydrogen Mission. Also underneath manner are thrilling makes an attempt to supply hydrogen in microbial electrolytic cells, the place electrochemically energetic microbes develop on anodes and oxidize natural matter — agricultural residues, even wastewater — and move the electrons generated to the anode (Current Science, vol. 128, p. 133, 2025).
The catalysis steps require costly supplies comparable to platinum, iridium, and many others. Ongoing analysis is geared toward changing these with cheap nickel, cobalt, and even iron. In early work in the direction of low cost hydrogen technology, the group of C.N.R. Rao at the Jawaharlal Nehru Centre for Advanced Scientific Research designed nickel-nickel hydroxide-graphite electrodes with a water-splitting functionality akin to platinum electrodes (Proc. Natl. Acad. Sci., USA, vol. 114, 2017). Combining such developments with photo voltaic, and microbe-driven processes can produce a gas that’s each green and cheap.
The article was written in collaboration with Sushil Chandani sushilchandani@gmail.com
