India's first green hydrogen train on track: It generates electricity & emits water vapour

INdia's number one hydrogen-powered rail ran a invigorated go down of trials betwixt New Delhi and Jind on Friday, with engineers tracking emergency braking distance and oscillation as the project moves closer to commercial service.The train touched a top speed of 120kmph on the Jind-Sonipat section during testing, though its operational speed will be set at 75kmph. An earlier round of trials had already been completed between Sonipat and Jind.The Railway Board had cleared the introduction of the ten-coach trainset in a May 22 letter. The railways ministry's announcement of the approval followed five days later, on May 27, but it is yet to announce a date for starting passenger services.Here's what is known about the project so far and how the technology works:The projectThe trainset is a retrofitted diesel electric multiple unit (DEMU) — a type of rake already common on short and medium-distance routes in India — which has been converted to run on hydrogen fuel cells instead of diesel.The retrofit was contracted to Medha Servo Drives, the Hyderabad-based railway electronics manufacturer, which partnered with Canada's Ballard Power Systems for the fuel cell technology.The train will have two driving power cars (DPCs) of 1,200 kW each, and the remaining eight carriages will be passenger cars. On this basis, the Railways says it will be the longest and most powerful (2,400 kW) hydrogen trainset in the world on a broad-gauge line.The railways intends to electrify most of its network, so hydrogen trains are largely being planned for lines that are difficult to electrify or involve heritage routes. For now, only 35 such train routes are being envisaged under the 'Hydrogen for Heritage' programme.Refuelling will be handled by a plant set up at Jind, where a 1 MW polymer electrolyte membrane (PEM) electrolyser produces roughly 420-430 kg of hydrogen a day, according to GreenH Electrolysis, the joint venture between Spain's H2B2 Electrolysis Technologies and the GR Promoter Group that built the facility under a 2023 contract with Medha.The site has 3,000kg of storage capacity and two dispensers for faster refuelling.On one cycle of fuell, the train can run about 250km.For now, the cost is estimated at ₹80 crore for each train and ₹70 crore for route infrastructure, besides the other developments. In a written Lok Sabha reply in December 2025, railways minister Ashwini Vaishnaw said a fair cost comparison with conventional traction systems was not yet possible, since the project and its infrastructure were still being developed on a pilot basis. Also read: India’s next great electrificationWhy it mattersMainly because it's clean technology. A hydrogen fuel cell produces electricity through a chemical reaction with oxygen, and the only by-product is water vapour, so the train has no carbon emissions at the point of use.This project puts India among a small group of countries that have built or are building hydrogen-powered passenger trains, alongside Germany, Japan, China and the US. Germany's Alstom Coradia iLint, which entered commercial service in 2018, was the first in the world.For Indian Railways, which has set itself a target of becoming a net-zero carbon emitter, electrification is the main priority and hydrogen is being pitched as the answer for the remaining gaps. These include non-electrified stretches, difficult terrain and heritage lines such as those in the Nilgiris, Darjeeling and Kangra valley.Also read: Pune celebrates iconic Deccan Queen’s 96 years of grand serviceHow a hydrogen train runsA hydrogen fuel cell works, in effect, like electrolysis in reverse. Where electrolysis uses electricity to split water into hydrogen and oxygen, a fuel cell combines hydrogen stored on board with oxygen drawn from the air, generating electricity and releasing water vapour and heat as the only by-products.This electricity then drives the train's traction motors, the same way an electric locomotive's motors are driven by current from an overhead wire, except that the hydrogen train manufactures its own supply rather than drawing on one.The positioning of the hydrogen tanks and fuel cells on board varies by design. Germany's Coradia iLint mounted its fuel cells and tanks on the roof of two of its cars, reasoning that hydrogen is far lighter than air and disperses upward quickly if it leaks, reducing the risk of an explosion, a 2024 peer-reviewed article published in ScienceDirect said.Switzerland's Stadler dedicated an entire carriage on its FLIRT H2 trainset to storage and fuel cells, isolating that equipment from passenger carriages altogether.Batteries are a standard part of the package in nearly every design, including India's. They store surplus electricity generated by the fuel cells and energy recovered through regenerative braking, supplying extra power during acceleration when the fuel cells alone cannot keep up, the ScienceDirect review said. Also read: Indian Railways to upgrade 100 Shatabdi, Jan Shatabdi trainsThe limitationsHydrogen rail is not a new technology being rushed into service. Alstom has been running hydrogen trains commercially in Germany since 2018, and Stadler's FLIRT H2 set a Guinness World Record by running 2,803km over more than 46 hours without refuelling.Green hydrogen, produced by splitting water using renewable electricity, is the only version of the fuel consistent with genuine decarbonisation. Most hydrogen made today is ‘grey’, i.e. Derived from natural gas or other traditional fuels. Producing green hydrogen at scale remains expensive, largely because of the cost of electrolysers and renewable power.Another concern is storage and compression. Hydrogen has very low volumetric energy density and must be compressed to high pressures, typically 350-700 bar, to be practical for onboard storage. That compression itself consumes roughly 6-10% of the gas's own energy content, according to US Department of Energy's hydrogen programme records.Hydrogen's small molecular size also permeates metals, a phenomenon called hydrogen embrittlement, which can weaken storage cylinders over repeated use and is a recognised safety concern in industries that handle compressed hydrogen, according to reviews in the International Journal of Hydrogen Energy and PubMed Central (PMC).Corrosion of metal storage and refuelling components from prolonged exposure to hydrogen is a related, long-documented problem, both the reviews said. It is why newer pressure vessel designs are increasingly shifting to composite materials rather than metals only.A third worry is operational stress. India's climate extremes and demanding duty cycles could test the resilience of fuel cells in ways that have not been fully proven outside more temperate operating environments such as Germany's.Cost efficacy and scalability of hydrogen-powered trains appears to be a long-standing issue. Despite the technology having been around for years, it is yet to catch up to public transportation powered by traditional fuels or renewables.