[JR1427]

What are the advantages to putting them between the rails, where you need trains to stop running in order to access them?

If it's about using wasted land, why not put them beside the rails, which would make access easier? There is usually a generous margin beside the tracks.

This would also allow bigger panels to be used.

[alnwlsn]

I think the idea is that you can make a machine that goes on the rails and installs them automatically. So you don't need to haul a bunch of equipment on site, you just drive one special train down the track once.

[Scoundreller]

Same for washing the panels. Could even work a system onto already-running trains.

And the RightOfWay is already maintained to keep thin grasses & trees away that may fall on a line.

Often the line is already built-up for flood prevention.

In some (most? All?) countries, the railway has free reign and doesn’t need to answer to city/municipal/states/provinces for approvals on anything.

A main “downside” is the poor production in winter/mornings/evenings on ground-parallel panels. e.g. France has huge solar capacity, they tend to be heavy electricity exporters in summer and heavy importers in winter. One of their new tariffs offers discounts except for 22 days in winter.

https://www.rte-france.com/en/data-publications/eco2mix/powe...

0 degree panels produce the most when electricity is valued the least.

Output should be measured in currency, not MWh.

[red-iron-pine]

"generous margin beside the tracks" is being, well, generous. there often isn't that much space, and it often already has cabling, phoneline, pipes, or other stuff there.

augur cars overturn the soil and lay pipe but now the fiber optic lines would compete with the solar.

meanwhile track lines are untapped, and often use electricity or having wiring for local induction loop

[foxyv]

I think the biggest advantage rails have is that they are electrified and are accessible by rail based maintenance vehicles. Panels have gotten so inexpensive that the major cost is usually the mounting, installation, and electrical access. Some of that is mitigated by installing on railways. You can automate the installation process and connect into the tram lines.