Last Updated on: 18th August 2025, 11:38 am

Alstom’s hydrogen train experiment has hit the buffers again, with operators in Germany reverting to diesel because replacement fuel cells are not available. Only four of the 14 Coradia trains Lower Saxony purchased are in operation. It is tempting to dismiss this as a simple supply chain hiccup, but the problem runs deeper. Following the thread back reveals not only the weakness of hydrogen in transportation but also a structural material constraint that makes it even less viable.

The Coradia iLint trains were always meant to be a flagship for hydrogen mobility. They use fuel cells supplied by Cummins, built out of its Hydrogenics legacy in Canada and Europe. Each train carries two modules rated at about 200 kW each. Fuel cells of that scale require 0.4 to 0.6 grams of platinum per kilowatt to achieve the durability demanded in rail service. That works out to about 0.2 kg of platinum per train. At today’s prices, that costs about $8,700, around 5% of the cost of the fuel cell. It sounds small until you set it against global production.

At the heart of every PEM fuel cell sits a thin membrane coated with platinum, and its role is both simple and irreplaceable. Platinum acts as the catalyst that splits incoming hydrogen molecules into protons and electrons. The protons migrate through the membrane while the electrons are forced around an external circuit, producing usable electricity. On the other side of the membrane, platinum again makes the reaction possible by speeding up the sluggish process of combining oxygen, protons, and electrons into water. These two reactions are fundamental to the device, and platinum’s unique surface chemistry allows them to happen at practical rates and with the necessary durability. Without platinum, the cell either fails to run efficiently or falls apart too quickly. That catalytic function is why every gram of platinum in a fuel cell stack is indispensable, and why fuel cells cannot escape their dependence on a scarce and volatile metal.

The platinum market produces about 250 to 280 tons per year. Roughly a third goes into automotive catalysts, primarily for diesel cars and trucks...