[delayed]

Solar cell is the only practically viable power source with no moving parts. Stop trying to attach it to moving things. Movements breaks things. Just put the panels by the rail, e.g. as vertical sound barriers in reasonable distance (to lower the pressure waves from train) from tracks. Or on a nearby field where it can be protected and inspected all at one place.

• Aurornis

  today at 5:10 PM

  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.

  • lefra

    today at 6:28 PM

    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.

• ryanmcbride

  today at 5:24 PM

  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?

  • dukeyukey

    today at 6:25 PM

    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).

  • acdha

    today at 5:53 PM

    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.

  • monegator

    today at 5:44 PM

    friends of friends simply need all that sweet government grant money

• SoftTalker

  today at 5:03 PM

  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.

  • dn3500

    today at 6:00 PM

    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.

This will never work, and it's ridiculous: https://youtu.be/7vItnxhWRqw

• syllablehq

  today at 5:16 PM

  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.

  • Aurornis

    today at 5:26 PM

    > 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.

    • saltcured

      today at 5:54 PM

      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.

  • ryanmcbride

    today at 5:26 PM

    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.

Bad website. No photo, only a video, and that wants to start with an ad.

Better article with video: https://www.swissinfo.ch/eng/emissions-reduction/solar-energ...

• 3eb7988a1663

  today at 4:25 PM

  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.

  • Aurornis

    today at 5:01 PM

    > 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.

What are the economics of this? Cost to install vs other available options? Durability will certainly be an issue I’m sure. Genuinely curious and not because I think it’s a bad idea. I want solar on all underutilized areas, I just prefer low hanging fruit from a cost perspective at the current time.

• LaurensBER

  today at 4:12 PM

  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.

  • tryagainian

    today at 4:24 PM

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

    • LaurensBER

      today at 6:26 PM

      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.

    • inglor_cz

      today at 5:14 PM

      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.

• datadrivenangel

  today at 4:11 PM

  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.

  • tryagainian

    today at 4:28 PM

    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.

• tryagainian

  today at 4:21 PM

  [flagged]

  • matwood

    today at 4:29 PM

    > Everywhere grid scale solar goes, expensive new transmission lines follow.

    How is this different than any other power generation install?

    • SoftTalker

      today at 4:39 PM

      Solar (and wind, I guess) is way more spread out? Other power generation happens at a point on a map by comparison.

      • Certhas

        today at 4:57 PM

        So requires more transmission infrastructure. The difference is that we already have that built out over decades, and now we need a different network in a much shorter timescale.

        No one should pretend that the energy transition is free. The final system we will arrive at can be ver

      • today at 4:43 PM

Always nice when something that I suggest in a random comment only to get a dismissive reply, turns out to be an idea worth persuing all along.

• Cpoll

  today at 3:47 PM

  > 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.

• therealpygon

  today at 3:59 PM

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

  • ben_w

    today at 4:30 PM

    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.

  • shermantanktop

    today at 4:23 PM

    Can you be wrong about your favorite flavor of jelly?

• kingstnap

  today at 5:29 PM

  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.

• baybal2

  today at 4:04 PM

  [dead]

Putting solar panels in familiar places is always popular as an idea, but rarely better than putting them on the usual roofs or as rectangular arrays on the ground.

> 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.

• ceejayoz

  today at 5:03 PM

  > 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.

  • Aurornis

    today at 5:14 PM

    > 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.

    • ceejayoz

      today at 5:25 PM

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

      Its sole purpose is power transmission, to the trains.

      • Aurornis

        today at 5:29 PM

        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.

        • ceejayoz

          today at 5:38 PM

          > 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?

  • mschuster91

    today at 5:09 PM

    > 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.

It makes more sense than the road, because at least the train isn’t driving directly on the thing. I wonder if the power could be delivered directly to the train. Although the only savings really would be transmission costs, not sure how big of a deal that is…

• JumpCrisscross

  today at 4:44 PM

  > 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.

  • hx8

    today at 5:03 PM

    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.

    • JumpCrisscross

      today at 5:22 PM

      > 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.

  • Epa095

    today at 4:59 PM

      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...

    • zdragnar

      today at 5:07 PM

      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.

      • Ma8ee

        today at 6:06 PM

        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.

      • happosai

        today at 5:13 PM

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

I don't know why people fall for this stuff. It doesn't make any kind of sense. You put the panels in a rectangular array in any convenient place. That's what wires are for.

Trains AND solar power. Awesome.

I'm in the south UK, live off grid, and have a bunch of solar panels, none of them are flat aside from the 640w of panels on my van, which generate almost nothing during the Winter.

Panels on the sides ot trains might be a better solution.

• CrzyLngPwd

  today at 6:13 PM

  WTF is the downvote for?

Solar sidewalks, solar roads, now solar rail?

WHY?! Dave from eevblog did the math and it's bad

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?

• Quitschquat

  today at 4:43 PM

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

• prmoustache

  today at 5:08 PM

  > 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.

  • leni536

    today at 6:21 PM

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

Today we sail

On the Solar Rail

For there's much we just don't know

So farewell with a kiss

Then it's fast for the mist

Till we're sleeping in the cold below

• Terr_

  today at 5:04 PM

  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

Would you be better off just building an additional nuclear power plant.

This trial tied the panels to the grid, but they want to connect it to railway substations or directly in to the trains power system for the traction motors.

Making the power only available for trains.

And never at night, as is typical with solar panels.

• comrade1234

  today at 4:17 PM

  An ETH study says no.

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

• golemotron

  today at 4:18 PM

  [flagged]