The Problem with Diesel on Heritage Lines
India's heritage railway lines, like the Kalka-Shimla and Darjeeling Himalayan Railway, are treasured for their scenic beauty and historical significance. However, most trains on these narrow-gauge tracks run on diesel engines. These locomotives, while
powerful, release a cocktail of pollutants, including particulate matter, nitrogen oxides, and carbon emissions. This not only affects the air quality for passengers and local communities but also poses a long-term threat to the pristine natural environments and the structural integrity of decades-old bridges and tunnels that make these routes so special. Electrification, the usual solution, is often impractical on these challenging terrains with sharp curves and numerous tunnels, and installing overhead cables would spoil the very beauty these lines are famous for.
How Hydrogen Power Offers a Clean Solution
Hydrogen-powered trains are essentially electric trains that create their own power onboard. The technology at their core is the hydrogen fuel cell. Inside the fuel cell, hydrogen stored in high-pressure tanks reacts with oxygen taken from the air. This electrochemical reaction generates electricity to power the train's motors. The beauty of this process is its only by-product: pure water vapour. There is no combustion, no smoke, and no harmful tailpipe emissions, making it a true zero-emission solution at the point of use. Many designs also include batteries to store excess energy, such as that captured during braking, which helps manage power for acceleration and climbing steep gradients.
Hydrogen for Heritage: The Vision
Recognising both the problem and the potential, Indian Railways launched the 'Hydrogen for Heritage' project. The initiative aims to run 35 specially designed hydrogen trains on ecologically sensitive and iconic routes. The primary goal is to replace ageing diesel locomotives and offer a clean, quiet, and sustainable travel experience. The Kalka-Shimla route, a UNESCO World Heritage site, is a prime candidate, along with other famous lines like those in Darjeeling and Ooty. By choosing these high-visibility routes, the project not only tackles pollution where it is most damaging but also showcases India's commitment to green technology and sustainable tourism on a global stage.
India's Progress on Hydrogen Rail
This vision is already becoming a reality. In July 2026, India launched its first hydrogen-powered train on the Jind-Sonipat route in Haryana. This pilot project serves as a crucial technology demonstrator, allowing Railways to gain valuable operational experience and build the necessary infrastructure for hydrogen production, storage, and refuelling. The experience gained from the Jind-Sonipat line is intended to be directly applied to the more complex heritage routes. While the initial operational speed is set conservatively, trials have been successfully conducted at higher speeds, proving the technology's capability.
Challenges and the Bigger Picture
Despite the promise, there are challenges. The cost of producing 'green' hydrogen—which uses renewable energy for electrolysis—is currently high. Building a robust infrastructure for production and refuelling across remote heritage locations also requires significant investment. However, these hurdles are part of a larger national strategy. The 'Hydrogen for Heritage' project aligns with India's ambitious National Green Hydrogen Mission and the broader goal for Indian Railways to become a net-zero carbon emitter by 2030. As technology matures and production scales up, costs are expected to decrease, making hydrogen a more viable fuel for wider application.
