> the railway was fitted with 48 specially-designed solar panels with a combined power of 18 kWp.
18 kW is less than what gets installed on a lot of houses. It took 100 meters to do this. The farther the panels get from the interconnect, the higher the losses along the line.
It’s easy to set up 18kW of panels in one spot. Covering an entire railway with panels would require a different transmission setup to get the power back to somewhere useful.
I really wish we could just forget all of these ideas to put solar panels in places that are highly trafficked and serving double duty. Just put them in unused space that isn’t used for anything else: Rooftops, empty fields, or over parking garages. I often get downvoted for saying this because a lot of people like these ideas of putting solar panels in space that they see, like sidewalks or roads or railways, but we have so much unused space that isn’t near foot traffic, road traffic, or railways that is so much cheaper and easier to use for solar. These projects usually turn into political grifts to get government funding because the ideas are not economically viable alternatives.