Now Solar Freakin' Railways! - Page 1
Forum section: electronics / general

author: dmcdonald
author_rank: Newbie
timestamp: December 26, 2021, 08:52:46 am
content: I do so hope the image provided is just some editor's idiotic ideaPutting solar panels between the rails might not be as bad an idea as a solar freakin' roadway, but it's still a stupid idea - it's dirty (from dust & lubricant contamination), high-vibration, and just utterly unnecessary - rail corridors almost always have significant unused space at the sides where panels could be better orientedhttps://www.pv-magazine.com/2021/12/21/solar-for-railways/

author: Psi
author_rank: Super Contributor
timestamp: December 26, 2021, 08:58:29 am
content: Agreed, there's way to much dirt/dust/oil/rust-powder covering rail tracks and generated by their use.The best place for solar panels is on a roof or in a solar farm.Maybe that will change if we get ~70% efficient panels that generate a kw and cost ~$10, but that's not going to happen for a while.

author: EEEnthusiast
author_rank: Frequent Contributor
timestamp: December 26, 2021, 09:04:50 am
content: The trains will be fitted with a wiping and cleaning mechanism. That will clean the panels, each time it passes over them???

author: NiHaoMike
author_rank: Super Contributor
timestamp: December 26, 2021, 01:21:53 pm
content: Why not put the panels on the trains?

author: f4eru
author_rank: Super Contributor
timestamp: December 26, 2021, 08:25:50 pm
content: Because trains have 10 000x less surface than railroad roofs or side walls.Because trains have too much aerodynamic shapes, and vibration.Because trains still care about space and weight, and passengers want large windows.Because trains have variable shadows when moving.Because trains are disconnected from the overhead network when not in use, and are subject to very harsh environments.Etc...Putting solar panels on a car, train, or road is basically just a PR stunt for getting subventions.Nothing more.Nothing else.Problem is that it just consumes resources and investments for no result.Yeah, taxpayers will take the bill.

author: nctnico
author_rank: Super Contributor
timestamp: December 26, 2021, 08:48:36 pm
content: Quote from: Psi on December 26, 2021, 08:58:29 amDid you ever care to investigate how dirty a solar panel gets on a roof and how that affects efficiency? I guess not otherwise you wouldn't have made this comment.Besides that, if people would have read the article carefully, they'd be aware that this project doesn't focus on putting solar panels between the rails but the aim is to find out what is the best way to incorporate solar panels in the railway infrastructure.

author: f4eru
author_rank: Super Contributor
timestamp: December 26, 2021, 10:17:01 pm
content: Yes. I investigated the panels on my roof, and dirt is making about 2% loss, after 7 years.Not even worth cleaning.Now OK, we have a strange phenomena called "rain"You probably don't get this in Netherland.

author: nctnico
author_rank: Super Contributor
timestamp: December 26, 2021, 11:10:36 pm
content: Quote from: f4eru on December 26, 2021, 10:17:01 pmBut did you actually check how dirty your solar panels are? I guess not.Rain doesn't wash everything away. Not by a long shot. I have roof windows at the same angle solar panels are typically mounted and these need regular washing in order to keep them clean. Otherwise a visible layer of dirt builts up rather quickly. But that doesn't mean that dirt prevents a solar panel from functioning (as you have found out). Circling back to the statement that solar panels near railroads get extra dirty and thus they are not going to work to satisfactory levels: it is BS.

author: ejeffrey
author_rank: Super Contributor
timestamp: December 26, 2021, 11:26:11 pm
content: Aside from an obviously silly photo what the article actually says is:"“If it is possible to generate energy along the widely ramified traction current network and feed it in directly, thereby making better use of the existing infrastructure and reducing energy losses through repeated conversion and transport..."Which is perfectly reasonable.

author: Psi
author_rank: Super Contributor
timestamp: December 27, 2021, 12:33:26 am
content: Quote from: nctnico on December 26, 2021, 08:48:36 pmThere is no need to investigate, common sense says that a roof of a house will get orders of magnitude less dirt on the panels than between railway tracks.Quote from: nctnico on December 26, 2021, 11:10:36 pmNo one said "near", we were all talking about putting them between the tracks, like in the photo.

author: nctnico
author_rank: Super Contributor
timestamp: December 27, 2021, 01:00:37 am
content: Quote from: Psi on December 27, 2021, 12:33:26 amYou mean the good old underbelly engineeringUse your underbelly for the only thing it is actually good at: tell you when it is time to eat. For everything else use real engineering methods (actual tests and a calculator). It is entirely possible that solar panels between the tracks remain cleaner due to the turbulence combined with rain around a train becoming a pressure washer. Nobody knows until it is tested; which is exactly what the people are going to do.

author: f4eru
author_rank: Super Contributor
timestamp: December 28, 2021, 05:42:50 am
content: Quote from: nctnico on December 27, 2021, 01:00:37 amYou just used your "belly engineering" to make a judgement before going to practice, and selecting two options from a range of many more. just sayin'It's an important part to make a judgement BEFORE wildly testing any crazy combination that you can eliminate by two calculations on a napkin, or by quick obvious judgement, logical thinking.People like solar roadways or batterizer make the same mistake in the other direction, they focus on one unique narrow solution to a wider problem, never ever make a sanity check, and get stuck in a very bad local maximum.

author: f4eru
author_rank: Super Contributor
timestamp: December 28, 2021, 09:41:53 am
content: Saying that, the important thing is also to consider all the parameters:it's nice if a train would hypothetically "pressure wash" a panel (still, ballast is way dirtier between the tracks than outside, because of lubrication, rust etc...)but rail is an extremely harsh environment.- between rails, there is immense vibration at each train, that could destroy your connections between panels. Faulty train wheels happen and induce incredibly big shocks on the rail.- wildlife will step on it, and crush the nice glass onto the ballast stone. That wildlife includes random drunk people, or hiker following/crossing the tracks.- People will steal anything valuable on the track level, like good old copper wire between panels, general purpose solar panels, etc...- ballast is a moving and settling stuff by design, and sharp edges will deform and crush panels from below.- trains occasionally drop stuff. Bolts, forgotten tools, poop and lubricant, sand, trash, people.... This will break a few panels- trains occasionally act like a car with an exhaust hanging onto the road : loose equipment will be mercilessly dragged on the ballast, and plow into every equipment there. Oh, a hanging chain just broke 200km of solar panel glass? Too bad. how many millions is that ?- trees and overhead equipment shade the tracksTo avoid or eliminate all those problems, the panels have to go up as much as possible. Putting panels between the tracks is about as bad as putting them on a bike path: 2-6 months, and they're trash.Roof, canopy or soundwall, or side bank is the way to go.Open canopy mounting has the big advantage that 23kV and height is quite a deterrent to thieves and vandals.Of course there is a fine equilibrium between the cost of support structure and the breakage level of equipment to make the most of the investment.Washing panels is not really a consideration. If it is, you've done something very wrong.

author: ejeffrey
author_rank: Super Contributor
timestamp: December 30, 2021, 08:56:11 pm
content: Quote from: Psi on December 27, 2021, 12:33:26 amThe photo above the article is not actually what the article is about. It is a photo from a different company that made a press release 3 years ago and never followed up on it. In online journalism photos are usually selected by a photo editor based on the general subject. They might be specific to the content of the article if that is available, but if not they will use a stock photo, an "artists conception" or really anything else. This is standard practice and many or most online publications do this.If they exist images within the body of the article are generally more tied to the specific content.

author: AlbertL
author_rank: Regular Contributor
timestamp: January 23, 2022, 01:27:14 am
content: Quote from: Psi on December 26, 2021, 08:58:29 amYes, the low-hanging fruit in terms of solar siting is still the vast rooftop acreage of warehouses, distribution centers, big-box stores and similar facilities. It's otherwise unused space, protected from damage, easy installation, with no negative environmental or aesthetic impacts.

author: thexeno
author_rank: Regular Contributor
timestamp: January 16, 2023, 10:15:40 pm
content: To bring a thread up from the dead... I recently read this news, totally related: a whole new (pilot project) type of solar railway in Switzerland, but a bit more modern (apologies, is in french, but I trust you can translate)https://www.rtn.ch/rtn/Actualite/Region/20230111-Une-premiere-mondiale-solaire-a-Buttes.htmlAny comment?

author: f4eru
author_rank: Super Contributor
timestamp: January 16, 2023, 10:44:28 pm
content: Switzerland has some money to burn....

author: ahbushnell
author_rank: Frequent Contributor
timestamp: January 17, 2023, 07:14:24 pm
content: Quote from: f4eru on December 26, 2021, 10:17:01 pmAlso mud.

author: AlbertL
author_rank: Regular Contributor
timestamp: February 07, 2023, 07:02:06 pm
content: Another problem is the effect of track maintenance activities on the panels and their wiring. For example ballast tamping, rail grinding and ballast cleaning.

author: dmcdonald
author_rank: Newbie
timestamp: March 31, 2023, 09:04:10 am
content: https://www.pv-magazine.com/2023/03/29/floating-pv-system-mysteriously-washes-up-on-hong-kong-beach/Putting solar panels on a large body of water - particularly saline waterAt least dust and falling debris aren't major concernsBut, I don't know:• corrosion• constant movement & flexing• risk of collision• fouling (e.g. from marine organisms)I guess the progenitor of this idea was able to disregard these with a bit of hand waving