Hydrogen on the long route: why India is the test case for diesel's replacement

On a freight corridor cutting through Rajasthan, a diesel locomotive still does most of the heavy lifting. That single fact is the starting point for one of the more consequential bets in the global energy transition.

Indian Railways runs one of the largest rail networks in the world, and a sizeable share of its long-haul routes remain on diesel traction because overhead electrification is prohibitively expensive across vast, lightly populated stretches. The logic is straightforward: where the wires do not pay for themselves, an alternative fuel has to. Hydrogen-powered trains, according to industry analysis cited this month by ThePrint, are now the leading candidate to fill that gap. India, on this reading, is not a peripheral market for the technology. It is the test case.

Why the long route matters

Electrification in India has accelerated sharply over the past decade, but the cost curve flattens well before the network is finished. Trunk corridors between the metros are now almost entirely wired, and the marginal economics of stringing catenary over secondary lines in low-density terrain are punitive. Diesel, by contrast, scales lineally with traffic and needs no fixed infrastructure beyond the fuel depot.

The trade-off has long been treated as binary: either the state funds the wire, or it keeps buying diesel. Hydrogen changes the terms. A hydrogen traction package can refuel at a wayside station, draw on indigenous or imported green ammonia, and substitute for diesel without the capital cost of full corridor electrification. For a network that still absorbs a substantial slice of the country's fossil-fuel import bill, that is not a marginal optimisation. It is a structural option.

ThePrint's reporting flags this as the defining logic: countries with vast rail networks and long, expensive-to-electrify routes are the prime candidates for hydrogen-powered trains, and India sits at the top of that list. The framing is not aspirational. The corridors exist. The diesel bill is already on the books. The question is whether the fuel and the rolling stock can be sourced at a price that survives contact with Indian operating economics.

The counter-narrative: batteries and biodiesel first

The hydrogen case is not undisputed inside India. Battery-electric multiple units have made rapid gains on short-haul and suburban services, where dwell times are short and depot charging is workable. Indian Railways has been deploying them in clusters around the largest metros, and the unit economics improve with every passing year as cell costs fall. For routes under roughly 300 kilometres with frequent stops, batteries are now the default argument against hydrogen.

Biodiesel blends, in turn, are the quiet incumbent. India has run blended diesel on portions of its network for years, and the supply chains, the procurement contracts, and the maintenance regimes are already in place. A switch to hydrogen implies writing off at least part of that installed base, and the diesel lobby, concentrated among public-sector fuel retailers, has not been quiet about the implications.

The honest read is that the three technologies are not competing head-to-head across the whole network. They are partitioning it. Hydrogen wins where electrification is too expensive and battery range falls short. Batteries win on dense, stop-heavy corridors. Biodiesel fills the legacy and the politically sensitive middle. Each has a constituency, and each constituency has a number it can put on a slide.

What is actually being built

The early programme is small but deliberate. Indian Railways has signalled interest in hydrogen-powered trains for specific routes in the northeast and for hill railways, where the combination of gradients, curves, and limited corridor width makes catenary expensive to install and visually intrusive in heritage zones. The procurement is at proof-of-concept scale rather than fleet scale, but the procurement is real.

The supply side is moving in parallel. Domestic green hydrogen capacity, built around solar and wind feedstocks in Gujarat, Rajasthan, and Tamil Nadu, has begun to underwrite long-term offtake contracts with industrial users. Rail would be a marginal new buyer in a market dominated by fertiliser and refining, but it would be a high-visibility one. A passenger train running on green hydrogen is a cleaner political artefact than a refinery pipeline.

The technology itself has matured faster than sceptics expected. Alstom's Coradia iLint, running scheduled service in Germany since 2018, established that hydrogen traction is workable in cold-weather, mixed-traffic conditions. Subsequent deployments in France and Italy have widened the operational envelope. The relevant question for India is less whether the technology works and more whether it survives Indian heat, monsoon humidity, and dust loads on traction packages not originally designed for them. None of those are deal-breakers on the available evidence. All of them are reasons to start small.

The stakes

If hydrogen scales on India's long routes, three things follow. First, the country's diesel import bill for rail falls, with the foreign-exchange and emissions consequences that implies. Second, a domestic market of credible scale exists for electrolyser manufacturers, fuel-cell stack makers, and green-ammonia producers, with the export potential that follows. Third, the political case for hydrogen in other large, partially electrified networks, from parts of Africa to Central Asia, becomes far easier to make.

If it does not scale, the more interesting question is why not. The likeliest failure mode is not technological. It is procurement. A programme of this size demands multi-year price commitments, depot-level refuelling infrastructure, and a maintenance regime that does not yet exist. The diesel and battery incumbents will compete hard for the same routes, and the political economy of Indian public procurement is not automatically kind to a fuel that requires a new supply chain.

What remains genuinely uncertain is the unit cost of green hydrogen delivered to a wayside refuelling depot in, say, Jharkhand, in 2030. The trajectories published by industry and by India's own hydrogen mission point in optimistic directions. They have done so for some years. The next eighteen months of actual procurement will do more than a decade of mission statements to settle whether the test case passes.

Desk note: where wire reporting framed hydrogen as a single global headline, this publication read it as a corridor-by-corridor question with Indian operating economics at the centre. The technology is proven; the procurement is not.

Wire provenance

This editorial synthesis draws on the following public wire/social posts:

• https://t.me/thePrintIndia
• https://en.wikipedia.org/wiki/Hydrogen_train
• https://en.wikipedia.org/wiki/Indian_Railways
• https://en.wikipedia.org/wiki/Alstom_Coradia_iLint