Not disagreeing, genuinely curious and hoping you know more than I do. Haha
You say minimum maintenance, but it seems like this would require almost constant maintenance to me. Animals shitting on them, trains blowing dust, rocks, shards of metal onto them, scratching their surfaces and diminishing their use over time by blocking sunlight from constant debris and scratching. Would it not make more sense to measure the height of the lowest bridge/tunnel on the track's route, and put these on a platform at that height? At that point, they could be angled, or even potentially have those motors that track the sun, while keeping them safe from damage from flying pebbles and dirt, and providing shade for the train to run under? I doubt the shade thing matters that much, but assuming these are passengers trains (I'm a USian, so I've only ever heard of passenger trains in folklore and western movies), it could limit the amount of air conditioning the train needed to keep passengers cool, perhaps?