Really long and thin strips that can't be angled. They can only be serviced while the track is closed and need to survive whatever debris a train might fling at them. Is this really the best way to place them?
Solar freaking railways.
For the life of me I don’t understand why people are putting them anywhere before every rooftop is covered with them. Roofs are dead space and unlikely to have debris issues (at least compared to a railway).
It's companies trying to make a quick buck. They tried this with roads too.
Obviously every home should have them first and all newly built homes should be built with solar efficiency in mind.
Deployment on rails is dirty cheap. Can be highly automated and you have highvolt power line just a few meters away.
If you put solar upon your roof, 2/3 of the costs are labor costs. The material bill encompasses electrics, mounting system, cables, and pv panels that can get reduced on railways as well.
Cheap if you only count the cost of plopping them down and walking away, the train could kick up enough dust and debris that efficiency is impacted significantly more than installing them on a roof would have been, necessitating installing new ones sooner.
It’s all theory. That’s why I think it’s worth a try and learn the facts.
Edit: A rough estimation with averages: 10 kWp gives 11kwh a year in Swiss, 1kwp panel costs 500€, 1kwh energy costs 0,28 EUR in Swiss. Panel material costs for 10 kWp is 5,000€ and earns you 3,080€ (11,000*0,28€) yearly. This shows the value of the idea.
Don't forget about the inverters.
Low voltage (such as the output from a solar panel) suffers badly from losses over distance. Centralised solar makes up for this by having a large amount of panels close to a central inverter. There is going to be a distance tipping point of cost vs losses, if this is short and you need a lot of inverters, that's going to become a major expense.
What if the train runs a street sweeper brush behind it to clean them off every time?
Roofs are actually not that great. Installation is expensive because you are working at height. Roof angles and directions are also not ideal on many houses. Compare it to a simple installation on a field: You just take some corn field, stop growing corn there and can put your panels on some cheap holders and you're good. You can access and service them without the danger of falling from a roof. You can install them on an industrial scale instead of a few square meters on every single roof. You need only one electrical installation.
People love to cry about the loss of agricultural space, but currently we are growing a lot of corn to convert it to fuel or to put it into biogas installations. If you convert those field to solar, you will get more energy from them. And the loss of a big monoculture that is using a lot of pesticides is also great.
Hell parking lots are massive areas of dead space, build them over the damned things, it'll help against the heat island affect and give shade.
Or in parking lots. It would also have the added benefit of providing cover for cars.
It seems like the sort of naive gimmick one might expect from a MAD Magazine cartoonist, or Elon Musk on a ketamine binge. It would work to an extent for a while, though whether the amount of electricity generated would justify the maintenance costs to keep it going is another matter.
The arguments against it are the power yield of a panel pointing upwards, and presumably covered with dirt shed by passing trains. That said, it would suffer less impact damage than photovoltaic roads/bike paths floated elsewhere (the occasional rock impact, as opposed to constant traffic). Also, there is a lot of track, so even if a segment generates little power, it adds up. Not enough to power electric trains, though possibly enough to offset the power bill after operating costs are taken into account.
I’m guessing this installation is an experiment to quantify these figures rather than a commitment to roll this out more broadly.
I’m guessing this installation is an experiment to quantify these figures rather than a commitment to roll this out more broadly.
No need to guess, it's right there in the article.
The whole point of the exercise is to put solar panels in the not best location. Otherwise this article would be about wireless power transmission from space.
Out of all places where you could possibly place a solar panel, this seems to me like one of the least practical ones. It's almost all drawbacks
Even just a foot to the left and to the right, they can install double the number of panels while avoiding most of the downsides.
air currents from trains, especially high speed ones throw rocks and debris everywhere.
As a practicing solar engineer, I don't like the idea of applying solar panels linearly because they can benefit much more from centralization meaning applying panels to an area, but to be honest I think it's cool that humans are discovering new ways to use these things.
Sunlight is everywhere, so bring on the solarpunk!
Well yeah, the space in between the rails currently isn't used for anything, might as well put it to use
I'm just wondering how much electricity you realistically can get from these panels as first of all they're straight up, so most sunlight will come at the panels under an angle, driving efficiency down. Then, I'm sure there is a lot of rail, so a lot of potential area but still... Versus the cost and required energy to install them, what would be the ROI, really?
ROI would take a lonnnnng time, in my view. It's the same idea as installing modules under asphalt roads or even above them. It's not really worth the O&M hassle whatsoever.
The same idea goes for installations like canals. They're linearly too so not the wisest use of modules. But the benefit of modules over water like that is lower rates of evaporation as the panels block the sun. Same is true for water department reservoirs that see lots of algae. The panels block the sun and choke out the algae.
But you're right about the shading. If these panels are installed in higher latitudes, then odds are they might never see the sun directly at certain times of the year. Usually solar designers only recommend flat horizontal mounting for modules in hurricane- or tropical storm-prone regions like near the tropics, or close to the Equator where the Sun shines directly overhead most of the year.
What I COULD see happening is if governments around the world start transitioning railroads to have H-frame structures that suspend feeder lines like what's used in electric trains with pantographs. If you set up those H-frames frequently enough, you have the underlying structure similar to carports and can install modules 4-10 modules wide. THEN you can utilize string inverters every 7-8 H-frames or so, converting the solar DC power into AC which can help feed the train loads as they pass or feed the grid.
Bonus of the above system is that over time, all trains including rail freighters become electric or at least hybrid to make use of the free power generated above them throughout the railway.
Lots of ideas!
I mean my city has a metro line that is electric rail. seems like stations having batteries and solar along with solar on the track would make some sense for the elevated areas.
I've always been an advocate of the canopies above train stations having solar panels to help power the local loads and maybe push power back to the grid.
Solar canopies are used in many other places like parking garages/lots and canals, so the technology is there.
I'm starting to wonder if it's the vibrations from the train that makes these installations risky. Those same vibrations would happen to in-track solar PV like what's shown in OP's article. It's certainly possible to design around, as the EU is showing!
yeah I have a hard time believing we lack engineering skills to prevent shaking in structures.
I don't think it's that as much as it is putting modules near trains that have glass prone to micro cracks that can highly accelerate degradation of the panels to the point where they start cannabalizing others.
Still, I think you could probably install modules with polymeric front sheets instead of tempered glass to fix that issue.
No such thing as an impossible problem for engineers! Only impossible costs ;)
No such thing as an impossible problem for engineers! Only impossible costs ;)
Makes me think of that one quote, "Any idiot can build a bridge that stands, but it takes an engineer to build a bridge that barely stands".
Three years ago EEVBlog already published a Video why this is a terrible idea: https://youtu.be/7vItnxhWRqw
Im not convinced much has changed since then. As a Swiss citizen it's a bit disappointing that a apparent cash grab like this is possible.
And this is why they only put 100m of panels, to test and validate the idea before commiting to any large scale project. As a swiss citizen too, I'm on the contrary quite happy to see those test projects to give a chance to new technologies (or ways to utilize said technologies) before any real investment.
I think the biggest limitations will be security, someone will definitely be trying to steal them
Isn’t this the case with all existing panels?
Tbh this video has poor arguments:
Crazy cheap deployment, but I don't think those panels will stand up to it very well. The vibration is bad enough, but metal fragments are the real threat, I suspect. I've been in a few rail yards, and vehicles that habitually get parked close to rails that are in active service have paint damage from tiny metal chips flying off the rails and wheels. Unless they have some kind of replaceable clear shield, those panels will not just get dirty, they'll get slowly sandblasted till not much light is actually reaching the photovoltaic panel.
Sweet bike path, don't wear headphones.
Mmmmm, not AS stupid as solar roadways, but them again, what is?
Having said that... How efficient can these panels be just sitting straight up like that? That'll already cut out some of the efficiency which isn't going to be very high to begin with with solar
I mean, the basic idea seems good, no heavy materials will drive daily on top of it, like with the solar roadways, but still... How much could you realistically get out of this?
It's not about "efficiency" in this form. It's scale. Efficiency prioritization is useful ontop of a single home, Scale prioritization is when you are laying down a million+ panels.
Once those are installed, they're pretty much permanent with minimum maintenance, and will keep providing power for decades.
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?
Imagine a street cleaning car. Now imagine that, as a light truck attachment. Now imagine that, attached to any train that goes over the tracks.
Or, just imagine, Something like this: https://www.alibaba.com/product-detail/High-Temperature-Resistant-Small-Size-Rail_1601599861898.html
I'd still say these are going to pick up enough scratches to effectively block out most light. Or, at least, that's the way my brain wants to think about it. Like the way headlights get dim over time because the plastic or glass casing picks up scratching and makes them hazy/foggy/look like sea glass. I'm not trying to suggest that's what will happen so much as trying to understand why it wouldn't. Even with the street sweeper hanging under the cow catcher, the bristles of the broom seem like they'd scratch the surface over time and limit light. I'm very certain much, much smarter people than me designed this and have accounted for those issues. I just... Don't grok how lol
More info: https://www.groupe-sncf.com/en/innovation/solar-power-between-rails
The company behind it seems to have already tried it a year ago, and the project is in pilot phase until 2028
One train even swerved to run over a solar panel that was getting away. /s
I see it's time for our yearly Sun-Ways post. Here are the old editions:
SOLAR FREAKIN’ ROADWAYS!
Gadgetbahn type shit
Everything about energy production and storage.
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