India's First Hydrogen Train Explained: Jind–Sonipat Run, Fuel Cell Technology and Hydrogen for Heritage

A new propulsion era: Railways worldwide have moved from steam in the 19th century to diesel and electric traction in the 20th century. Hydrogen-powered trains represent a third generation of propulsion in which hydrogen fuel cells generate electricity on board, eliminating both diesel combustion and the need for overhead electric wires. With this launch, India joins a select group of nations — the Prime Minister noted that only three or four countries currently have the capability to run hydrogen trains.

India's specific achievement: India's train is distinctive on two counts. First, scale: while hydrogen trains abroad run with two to four coaches, India's train has ten coaches with 3,200 horsepower, making it the most powerful and longest hydrogen train in the world. Second, indigenisation: the train was designed, engineered, and integrated in India, reflecting Atmanirbhar Bharat in advanced railway technology.

The fuel cell principle: A fuel cell is an electrochemical device that converts the chemical energy of hydrogen directly into electricity. Hydrogen is fed to the anode and oxygen from air to the cathode; across an electrolyte membrane, they combine in a controlled reaction that produces electricity, water vapour, and heat — with no carbon emissions. This electricity drives the train's traction motors, typically supported by batteries that store surplus energy and assist during acceleration.

Onboard configuration: In the Jind–Sonipat train, hydrogen is stored in cylinders at 350 bar pressure in the two driving power cars (220 kg each, 440 kg total). The fuel cells in these power cars convert hydrogen into electrical energy that powers the entire 10-coach rake. Since the only by-product is water vapour, the train is a genuinely zero-emission mode of transport at the point of use.

Fuelling infrastructure: A hydrogen plant with a storage capacity of 3,000 kg has been set up at Jind, where hydrogen is produced through the electrolysis of water — the process that splits water into hydrogen and oxygen using electricity, and the key element of green hydrogen generation. A stable 11 kV power supply has been ensured for the plant, and refilling the train's onboard cylinders takes about four hours.

DEMU retrofit model: Rather than building an entirely new trainset, Indian Railways retrofitted an existing Diesel Electric Multiple Unit (DEMU) rake — replacing its diesel engines with the hydrogen-electric propulsion system. This retrofit approach lowers costs and demonstrates that legacy diesel stock can be converted to clean traction.

Institutions involved: The project was executed to specifications framed by the Research, Design and Standards Organisation (RDSO), with the hydrogen-powered driving power cars tested at the Integral Coach Factory (ICF), Chennai. A sum of about ₹111.83 crore was sanctioned for the pilot, covering the DEMU conversion along with hydrogen production, storage, and refuelling infrastructure. Loco pilots were trained at Shakurbasti (Delhi) and ICF Chennai; operationally, driving the hydrogen train closely resembles driving a DEMU.

Layered detection and auto-shutdown: Since hydrogen is highly flammable, safety standards on the train are stringent. The train is fitted with 15 hydrogen leak detectors, seven heat detectors, and three flame detectors; if any incident is detected, the system shuts down automatically. Each driving power car has eight fans (for ventilation and dispersal of any leaked hydrogen) and six CCTVs. Hydrogen leak and flame detectors are installed at the fuelling plant as well, creating end-to-end safety coverage from production to propulsion.

The scheme: Announced in the Union Budget 2023–24, Hydrogen for Heritage envisages running 35 hydrogen trains on various heritage and hill routes of Indian Railways, at an estimated cost of about ₹80 crore per train plus around ₹70 crore per route for ground infrastructure.

Why heritage and hill routes: Heritage lines such as the Matheran Hill Railway, Darjeeling Himalayan Railway, Kalka–Shimla Railway, Kangra Valley, Bilimora–Waghai, Mhow–Patalpani, Nilgiri Mountain Railway, and Marwar–Devgarh run through environmentally sensitive terrain where electrification with overhead wires is difficult and costly. Hydrogen trains need no overhead electrification, making them ideal for such non-electrified, ecologically fragile sections while eliminating diesel smoke from scenic tourist routes.

Jind–Sonipat as the testbed: The Jind–Sonipat pilot precedes the heritage rollout. Its operational data — hydrogen consumption, reliability, maintenance, refuelling logistics, and running costs — will shape the wider deployment. Initial running costs of hydrogen trains are expected to be higher and to fall as numbers scale up.

The Mission: The National Green Hydrogen Mission was approved on 4 January 2023 with an outlay of ₹19,744 crore, targeting production of 5 million metric tonnes (MMT) of green hydrogen per annum by 2030, along with about 125 GW of associated renewable energy capacity. It aims to make India a global hub for green hydrogen production, usage, and export, supporting energy independence by 2047 and net zero by 2070.

Types of hydrogen: Hydrogen is classified by production pathway: green hydrogen is produced by electrolysis of water using renewable electricity (near-zero emissions); grey hydrogen comes from natural gas without carbon capture; blue hydrogen is fossil-based but with carbon capture and storage; brown/black hydrogen comes from coal gasification. The Jind plant's electrolysis-based production aligns the train with the green hydrogen pathway.

Railways' decarbonisation goals: Indian Railways has achieved nearly complete electrification of its broad gauge network — the Prime Minister cited 99% electrification — and aims to become a net zero carbon emitter. Hydrogen traction complements electrification by decarbonising the residual non-electrified and heritage sections, while insulating operations from imported fuel shocks, a point underscored amid the West Asia conflict and the Strait of Hormuz disruptions.

Global pioneers: Germany ran the world's first hydrogen-powered passenger train, the Coradia iLint (developed by Alstom), which entered service in 2018, and later operated hydrogen trains on regular routes in Lower Saxony. China and a few European countries have also demonstrated hydrogen trainsets. Globally, however, hydrogen rail is still in early stages — the technology has existed for only about 7–8 years, and most operational trains abroad are short, two-to-four-coach units.

India's differentiators: India's entry combines the largest capacity (2,600 passengers), the longest consist (10 coaches), the highest power (3,200 HP), indigenous design, and a retrofit pathway that can convert existing DEMU stock — a model relevant to other developing rail networks.

Significance: The project advances India's climate commitments under the Paris Agreement, showcases indigenous capability in a frontier clean technology, creates a domestic ecosystem for electrolysers, fuel cells, and hydrogen storage, and offers a template for clean mobility in hard-to-electrify transport segments such as heritage railways, and potentially shipping and heavy trucking.

Challenges: Green hydrogen remains costly relative to diesel and grid electricity; producing, compressing, storing, and handling hydrogen safely requires specialised infrastructure; refuelling times (about four hours) constrain fleet utilisation; and lifecycle emissions depend on the electricity source used for electrolysis. Scaling from one pilot to 35 heritage trains will test cost reduction, supply chains, and safety regulation.

The Jind–Sonipat pilot must now generate rigorous operational evidence — on hydrogen consumption, fuel cell durability, refuelling turnaround, and per-kilometre costs — to guide the rollout of the 35 trains under Hydrogen for Heritage. Indian Railways should co-locate green hydrogen production with railway solar and renewable capacity so that the fuel remains genuinely green, and progressively indigenise electrolysers, fuel cell stacks, and high-pressure storage under the National Green Hydrogen Mission's manufacturing incentives. Safety regulation for hydrogen handling at stations and depots should be codified into national standards through RDSO, and refuelling times reduced through higher-capacity dispensing systems. Converting heritage steam and diesel routes to hydrogen will marry conservation of railway heritage with climate goals, while lessons from rail can seed hydrogen use in buses, trucks, and shipping. With sustained research on cost and efficiency, hydrogen traction can become a durable complement to electrification, taking Indian Railways towards its net zero ambition and India towards energy independence by 2047.