Canada

The major problems with hydrogen-electric cars are that hydrogen tanks are expensive and difficult to build, and that refuelling stations aren't exactly common.

Hydrogen-electric trains make much more sense, as the tanks scale well-- large tanks are more efficient storage than small ones-- and the fact that trains have set routes makes adding hydrogen infrastructure much simpler. As well, it likely wouldn't be difficult to extend range by simply adding more tanker cars behind the engine.

This is great news, and I hope the pilot project goes well and is expanded

This is not as good of an idea as you may think.

First is where the hydrogen comes from. Most commercially available hydrogen comes from fossil fuels. The most common process involves superheated steam, methane (aka natural gas), and a catalyst. Very little hydrogen comes from renewable energy via hydrolysis.

Second is efficiency. The total process of transforming renewable energy to hydrogen, storing and transporting the gas, then using it to move a locomotive is only about 30% efficient. There are significant losses at every stage, and it’s a very complex supply chain.

Now, compare this to very boring overhead electrified railroads, which have existed for over one hundred years. Modern systems can achieve nearly 85% efficiency from generation to locomotion, are cheap and easy to build, and have some of the most reliable rolling stock around since they’re essentially a really big slot car. The only downside is the big up-front investment in overhead lines, but that quickly pays for itself with the overall efficiency of the railroad system.

If you ask me, this is a bad idea. It’s somewhere between well intentioned but poorly thought through engineering, and the good old fashioned greenwashing of the fossil fuel industry.

I'd pay to not smell diesel fumes on the train.

Hydrogen sucks for cars. It kinda sucks for trains - battery-electric probably still makes more sense. But for jets, hydrogen could be a real winner. So, on that front, we have now tested hydrogen jets:

https://www.theverge.com/2022/11/29/23483889/rolls-royce-easyjet-hydrogen-fuel-jet-engine-test

Also it doesn't entirely matter that most of the hydrogen comes from cracking petrochemicals presently. Of course it's not ideal but you need the infrastructure in place to transition into green hydrogen as production picks up. You also need someone using hydrogen to justify investing in green hydrogen.