Those trains already exist. Germany is also testing battery electric trains: https://www.alstom.com/press-releases-news/2022/1/alstom-and-deutsche-bahn-test-fir

Those trains already exist. Germany is also testing battery electric trains: https://www.alstom.com/press-releases-news/2022/1/alstom-and-deutsche-bahn-test-first-battery-train-passenger-operation https://www.alstom.com/press-releases-news/2022/1/alstom-and... Hydrogen cost is going to be decisive. Right now most hydrogen is produced using natural gas (so called grey hydrogen). Green hydrogen production with renewables is only happening on a small scale and is typically still more expensive than grey hydrogen. Long term (decades) this might become the cheapest and dominant way to produce hydrogen though. But for now, it's not an option for most hydrogen consumers. Blue hydrogen (grey with carbon capture) is something oil and gas companies love talking about but otherwise is not something that seems to be implemented at scale in the real world by anyone. And that too is going to be more expensive than grey hydrogen as it is basically the same process plus cost for capturing carbon. So, as gas prices are high right now and there's a shortage. Hydrogen prices are going to be higher and using it for transport is not going to have a high priority. And when it comes to efficiency, you are actually better off just burning natural gas as fuel than using it to produce hydrogen. You release less CO2, the emissions aren't that bad, and it's a much more efficient way to use the gas. So, these hydrogen trains are anything but green or affordable right now. They would be nice if we had cheap green hydrogen. But we don't just yet. And we probably won't have that for quite some time. So, yes, battery electric trains are the obvious move from a cost point of view. The charging infrastructure is already there. Just ride the train onto any rail segment that is electrified and take some juice in. It's probably not a whole lot more complicated than that. And you could electrify rails around e.g. stations so trains can charge while they stop there.