Or don’t put the panels near a railway at all. We have so much land and even empty rooftops that would be easier and safer to use first. Running panels along a railway means the electricity has to be carried all the way back to some point, meaning either giant cables to handle the current or specialized equipment and high voltage transmission lines. None of that was addressed by this pilot program that was 100 meters long.

You can do a pilot test of solar panels anywhere and call it a success, but the real test is scaling it up in an economically viable way compared to alternatives. None of that was tested.

Putting panels in a line is the worst arrangement. Just put them on roof tops or fields and keep it to places where they don’t have to be armored and reinforced.

Conveniently, there's already an electric cable sized to transport a few MW nearby. This might reduce the cost of installation, also there'll be no land acquisition/impact study issues.

However, I agree that putting solar panels in between or near rails will increase the cost of maintenance: the technicians will need to travel longer times to the work site, and now they also need to be certified to work near railroads.

I'll never understand why people latch onto these kinds of solar "solutions" in search of problems. Like that solar roadways fiasco a decade or so ago.

Just normal-ass solar is already safe proven and effective. Why do we need to remix it when there are still so many easy wins to be achieved?

It does seem kind of silly to put the panels between the rails, more prone to damage there from stuff falling off the trains, derailments, etc. and not angled for optimal sun exposure though I guess it's easy open space.

Before I read the article I was thinking the electricity from the panels would power the trains but doesn't sound like the output is enough.

That video is good - seeing the train-car dropping the panels into place makes it clear that you have some immediate labor savings on the initial deployment. Not sure if the post-installation labor was significant or could be automated away.

Still not sold on the idea. For something with a 20+ year life span, the initial deployment effort seems kind of irrelevant and should be better located somewhere that does not require ongoing activity. Train ballast requires replacement every N years which is going to require ripping up all of those panels.

WTF is the downvote for?

An ETH study says no.

https://lenews.ch/2026/07/04/new-nuclear-plants-a-difficult-...

Cold: the metal boxes going

Hard: the tracks on which we roam

Panels when the dark's not coming

Feel the weight of what we tow

I think these kinds of ideas capture easily impressionable, elected representatives whose technical knowledge is non existent.

And yet it did work, with positive results shown over a year, right? It seems that the reasons why this "could never work" like cracks, dust, and vibrations might have perfectly reasonable solutions. Solar panels have gotten so cheap that it might not be as important to install them in perfect conditions, and other factors like real estate, ease of maintenance, access to the grid come into play in interesting ways. I suppose long term results are yet to be seen, but it doesn't seem ridiculous to me.

People hate the idea of solar in currently-unused space. Even if that space is bare desert. So you can get a big PR boost if you propose "solar, but on a thing" (roadways, water, and now trains).

Yeah, I can understand putting solar on things when it lets them become standalone off-the-grid setups but for something like railroad track it’s just not that much space and the costs are so much higher. Except on the tightest urban lines, just putting rows of normal panels next to the tracks should be significantly more space with much easier engineering.

friends of friends simply need all that sweet government grant money

> idea worth persuing

Remains to be seen, considering how much snake oil there is in the solar market (but to be fair, this makes more sense than solar roads). A news article summary of a press release isn't proof of much.

> Did we really fill up all the area on top of roofs, parkings lots, industrial areas, etc., and we're running out, and we have to put solar cells on railroads?

I guess it is easier to control the deployment since they own the railroads.

They're getting 180 watts per meter, so it would take 50 km of panels to power one high speed train. And that's when the sun is shining. Double this at least if you want to store the energy and run trains in the evening.

> at least the train isn’t driving directly on the thing

It’s just kicking up dust and dripping lubricant onto it.

Maybe this makes sense. I’m deeply sceptical. Especially when you could just be putting vertical panels to the sides.

Being right about things you have no control over is a bit like being right about your favorite flavor of jelly.

These are not ideas worth pursuing from an engineering standpoints. It doesn't make any sense compared to just doing the cheap and proven at scale thing of just placing them in normal fields.

But I will agree that the idea has proven marketing merit. This is a class of truly top tier snake oil. The solar roadways people continue to go unbelievably far on almost the same grift.

> seeing the train-car dropping the panels into place makes it clear that you have some immediate labor savings on the initial deployment.

Dropping panels in place is not the hard part. Getting all of that electricity back to a connection point is one of the many problems created by this idea.

Putting panels in a multiple kilometer long end-to-end row is very inefficient compared to rectangular layouts that can be clustered around connection points.

there may be solutions to it but there are just already existing places to put solar panels that don't even require coming up with solutions.

> It took 100 meters to do this.

Thankfully, Switzerland has lots of meters of railway.

> Covering an entire railway with panels would require a different transmission setup to get the power back to somewhere useful.

There's caternary on 99% of Swiss rail, every few dozen meters, that already transmits power.

I imagine that the cost to install is fairly low since train tracks require regular monitoring and maintenance so it's fairly cheap to add the installation and maintenance on top of the existing schedule.

The manufacturer claims that durability should not be an issue. Time will tell.

Seems likely that safe access for maintenance makes this unappealing economically. Likely easier to have wider rail right of way and then put a panel farm on the side.

> And yet it did work,

You can put panels on anything and generate power for a couple years.

This system was only 18kW. That’s less than what we put on some residential houses. They didn’t address any of the hard parts like a transmission system capable of scaling up along a linear row of panels extending kilometers long.

> Solar panels have gotten so cheap that it might not be as important to install them in perfect conditions, and other factors like real estate, ease of maintenance, access to the grid come into play in interesting ways.

They had to use special panels for this, not the cheap ones you know. Any installation in an area like this requires reinforced and protected panels, which are more expensive than what you’re thinking.

You did identify some of the problems: Maintenance on this is terrible. They’re not going to shut down train routes to fix problems with the solar, so when something breaks it’s probably broken for years until a maintenance window can shut down transpiration.

Access to grid is terrible. You can’t re-use the train power lines, so I guess we’re running new transmission lines? A linear array is the worst possible configuration for a solar array because it maximizes the transmission distance and starts to require high voltage equipment to work.

Would you ever think it would be a good idea if someone suggested we go put solar panels out in the middle of nowhere between towns? Or would you agree it’s better to put them close to the towns on unused space like rooftops where they can feed directly into local loads? I think the visual of putting these on train tracks is misleading a lot of people into thinking we’re getting something for free when really this is an absurdly expensive way to place and connect solar panels.

And all the train depots and train stations are already covered in solar panels, I presume.

This is incorrect, you mean 180 kWp/m.

> in one year, the project has produced around 16,000 kWh.

160 kWh per meter.

  Urban Metro / Trams: 2 to 10 kWh/km

  Commuter Trains (EMUs): 4 to 12 kWh/km

  Regional / Intercity Trains: 6 to 20 kWh/km

  High-Speed Trains: 15 to 60 kWh/km

  Freight Locomotives: 10 to 50+ kWh/km

Of course.

I have tried entrepreneurial stuff twice before, in my 20s, though without much success. Having ideas good enough to get investors interested is a sign that perhaps I should have another go at it.

  Initially, he planned to remove dust from the surface of the photovoltaic cells using a cylindrical brush mounted on the rear of a train. “However, we realised that each time a train passes, it creates an airflow that sweeps away all the dust,” he said.

https://www.swissinfo.ch/eng/emissions-reduction/solar-energ...

It's solar, of course the unit economics are going to pencil out positive in the majority of climates and energy markets. The real question is "why should we put them here instead of somewhere else."

I wonder if the benefits are legal/jurisdiction/political. The total amount of track they could install this on is huge, and it doesn't seem like something that will be disagreeable on the local level. It could just be the easiest place to put it to deal with property law and zoning etc.

Another political benefit is that it means work for a very large number of jurisdictions, as there are suitable tracks just about everywhere.

Can you be wrong about your favorite flavor of jelly?

> Thankfully, Switzerland has lots of meters of railway.

The linear meters of railway are nothing compared to the square meters of rooftops. Putting panels in a long row is the maximally worst arrangement you can come up with.

> There's caternary on 99% of Swiss rail, every few dozen meters, that already transmits power.

I guarantee this wasn’t oversized to accommodate power transmission duties, too.

It’s also high voltage line. The solar setup would need additional and expensive high voltage equipment to interface with the line and to work within the design parameters of a line that was designed to deliver to the train, not carry extra power.

You could put the panels anywhere else and connect them normally to the grid like every other installation.

> There's caternary on 99% of Swiss rail, every few dozen meters, that already transmits power.

Switzerland runs on 15 kV catenary voltage. Transformers suitable for that kind of voltage cost a lot of money.

With the added benefit of being able to mount the tracks at an angle, and the added disadvantage of occupying area near the tracks that is occasionally used for maintenance equipment.

And getting approval to widen the right of way, where it’s even physically possible, and issues around flora suppression.

It could make sense along an electrified rail line, if the power lines used to supply the trains can be leveraged for distribution?

But, putting panels between the rails seems foolhardy to me too.

Placing a cover over the area between the tracks makes it much more difficult to inspect the ties (sleepers) and ballast.

> It's solar, of course the unit economics are going to pencil out positive in the majority of climates and energy markets

This is far from an of course. There were idiots trying to do solar roads a few years ago. The math didn't pencil out.

That seems pretty optimistic in the long run. Even a high power leaf blower won't get all the dust off of a dirty surface, especially if any sort of hydraulic oil, bearing grease or other viscous fluid mists onto the surface.

> I guarantee this wasn’t oversized to accommodate power transmission duties, too.

Its sole purpose is power transmission, to the trains.

I'm not an expert but I think the SBB is already pretty good at handling this. I think they already run measuring wagons (Oberbaumesswagen) with grond penetrating reader and ultrasonic measurement and use flow sensors to monitor drainage.

I would expect that the solar panels impact the efficiency at least somewhat but apparently not enough to cause real and enough issues for the SBB or perhaps they see ways to improve this in the future.

Yes, worsened inspection is a non-trivial problem. Very high quality sleepers (I wouldn't expect any other kind in Switzerland) mitigate this, but copying such approach in other countries could spell trouble.

One thing that has struck me with our own solar panels is that they have to be very dirty before I notice any significant degradation in efficiency. And when they do get completely covered in pollen or leaves, a brief rain is usually enough to clean them.

At least trains no longer drop literal shit between rails...

You understand that wire doesn’t have infinite capacity, right? You can’t just point to a wire and say “problem solved”.

I can’t even tell if you’re honest or just trolling at this point in the conversation.

> You understand that wire doesn’t have infinite capacity, right?

Why would it need that? Your original complaint was "18 kW is less than what gets installed on a lot of houses". Which is it? Too much to handle or too little?