View Topic

Bumping this!

I happened to bump into an article on this yesterday...the solar tiles are being put to their first actual test in a public square in Idaho! 30 tiles placed along the sidewalk are being used to power the public square, including a fountain and its restrooms, and a webcam has been installed to let everyone watch the tiles in action (the tiles give a sort of light show at night). I don't know about you, but when I see stuff like this I get really freaking excited about the future.

Article: https://www.engadget.com/2016/10/02/solar-roadways-public-test/
Live Webcam: http://www.sandpointidaho.gov/visiting-sandpoint/solar-roadways#ad-image-0

Oh no... oh no...

Also wow this is an old thread...

Okay... now... I may rain on your parade here, and so I preemptively apologize I really don't want to hurt anyone's feelings...

Now this is my specialty, while I my specialty is Nuclear Engineering, that didn't play a big part until 3rd year of my degree. (In-fact I did my case study last year on wind farms) I focus on energy and generators and their efficiency specifically.

I'll try not to rant too much here, if anyone wants I can talk for much longer about this stuff...

Let's start on a positive: these things are cool, they are a great novelty and are probably pretty nice in public spaces and large areas, could be really fun.
So my problems isn't with this installation or the technology itself, it's really nice, and when I went on the stream some people were really enjoying it.

My big problem is with the hype and misinformation from the company and the media...

Lets start with this installation: it's already broken down and required maintenance twice since it's installation which I really had to dig to find out   several of the LEDs and panels on the blocks are still broken though, you can see it if you check the stream... additionally that little installation cost $500,000... that's an exceptional amount... for example at my Uni we set up a piezoelectric demonstration where you step on panels and it lights up LEDs for about £100 and covering about half the area of that installation... Also the panels aren't powering the whole square, they themselves are even still connected to the grid in the standard renewable arrangement with a smart controller regulating them, while they are wired to the fountains and toilets they would only be powering them when functioning at the peak of peak efficiency, ie Sun directly overhead, no shadows falling on them, even then it's just lighting...

Okay, that's just this installation, it's an early prototype and we can imagine the coverage is trying to be optimistic.

First off, putting a solar panel behind a glass pane will reduce it's efficiency by between 40-80% depending on the transparency rating of the glass, and the optimum receiver wavelength of the panels, that's assuming it's working perfectly and there's no detritus or damage on the surface. Most industrial panels, even ones installed on your roof try to minimize the cover as much as possible, they are usually really thin often poly-reinforced glass, if they have covers at all.

Large solar installations use the best solar panels with the highest efficiency; which is about 100W per 10m² these are ridiculously expensive though, and thus usually only used for large scale operations, they also require consistent polishing and maintenance, the idea that you can set these up, cover them, put them on the ground and just let them run is kinda silly, at least without massive maintenance infrastructure.

Glass as roads? Asphalt and Concrete are used for roads for a variety of reasons, 1] Cost 2] compression strength 3] easy to repair. 4] Very high friction coefficient.
Glass is literally the opposite of all of those things, it's expensive, is weak under compression, requires a full refit if damaged and has an extremely low friction coefficient. Most transparent plastics suffer the same problems though they are usually much better under compression forces.

Transmission of power? A few problems with this, most of which are a little complex :/ but I'll try and explain. Power is transmitted across countries and the world at very high voltages, this is because loss is very dependent on current, to simplify P_loss = I²R and the higher the voltage the lower the current and thus the lower the loss. Solar panels cannot interface with very high voltages without risking a complete failure, in theory they could... but it would be very VERY expensive and dangerous.

Additionally for all our devices from lights to supercomputers rely on the idea that the frequency of power and it's supply remains the same (in the US it's 60Hz and in the UK we use 50Hz) in order to maintain this distribution and transmission networks as well as power plants have to keep a constant eye on supply and demand, while low level smart controllers like the ones they are using in Sandpoint can mitigate solar's inherit issues with this, its only so much, which is why centralized solar generators or ones attached to single properties are good; solar doesn't work well when spread out, unlike wind power which works really well as a distributed network because its easily and efficiently controllable.

As I say sorry for all this, but I really had to set the record straight, there are more issues but I wanted to keep this on the shorter side of a book... I think a much more efficient method is lifted solar panels above roads, that way you get more power, they can rotate to keep in the sun and are much less likely to be damaged. Solar power is great, I myself use it for lots of things and it defiantly has a big part to play in the future, that's my main problem with all this... I think this sort of misrepresentation hurts solar and people more than the truth.

I'm not going to pretend like I'm an expert at the science, but I do know that this is a small test and that solar power as an energy source is becoming better, cheaper, and more efficient every year. I imagine that if this were something that took off the cost of making and repairing them would go down due to economies of scale as well...and at the end of the day, the power doesn't necessarily have to travel very far...just to your house by the road. If there are a lot of these things, each individual one may not need to generate or transmit much power.

And even if what you say is true and can't be overcome, there are still many benefits behind this technology...smart roads that don't need to be repainted and resist snow and ice cover, for example. I still think it's very promising technology that's very early in development...we'll see where it goes.

One word: Maintenance. Solar roads would be an absolute bear to maintain. We have trouble with painted asphalt, let alone complex electronics connected to a power grid. Lets solve some more realistic problems first and invest in normal solar plants.

I know my post was really long, but I think I covered most of this in it oh well

Solar can even be really effective, but it's much much better above the road not as it.

And smart roads could work really well... just don't make them out of glass

Solar-Roadways as I said is a nice thing for installations and squares like this.

I spared you thermodynamic and power equations showing that it isn't just about efficiency...

But for what you said about distance and homes, domestic energy consumption only accounts for about 30% of global demand the majority is in commercial, industry and especially heavy industry: which includes glass, copper and silicone manufacturing (what a solar panel is mostly made out of). These need very high voltages and powers to function at all.

Any way solar is a very important source of power, though it has it's limits, I think people viewing everything related to it with rose tinted glasses does it a disservice.

I think this idea can be put to use to create sections of smart roads, perhaps as a publicity stunt (would look great in Times Square for instance). As far as generating power for general usage? Not so much I don't think. Much better to put solar panels on our roofs or something.

I've argued against these things since I first saw them. This is gonna have to be extra thick, sturdy glass.. and every millimeter of glass you add will reduce the efficiency of the solar panels. Roads also have to put up with massive stresses.. not just the huge vehicles driving on them, but also seasonal variations in temperature and humidity, which causes the ground underneath the road to move slightly. We're also talking about a surface (the road) that is in shade whenever a car is over it. Also.. your tires wear out over time.. the rubber on the tires is going somewhere, and that somewhere is usually the road. I'd expect that if these panels provide any traction at all (they better! even when cold and wet!) that much of that rubber will end up on the panels. It will require constant cleaning in order to be even a little transparent.

Dunno.. I guess I don't know everything but I could go on and on about the reasons why this is a bad idea. Engineers use asphalt for really good reasons. We shouldn't really be putting our solar panels UNDER things anyway.. They should be over things, so they get maximum sunlight. We also shouldn't be stretching our panels out into long road shaped segments, because photovoltaic cells generate direct current at small voltages, which have lose a lot of energy to heat over even very short distances. You'd need to convert to AC and step up the voltage or REALLY step up the voltage.. Dangerous ideas. Generally we require such high voltage cables to be either very high up or very deeply buried for safety reasons, and this would put it all right there on the surface... Not to mention the efficiency losses when you step up the voltage.

Here am.. going on and on. Sorry.

No offense, but we have a lot of Negative Nancies here.

So what if it never realizes its full potential? The awesome thing about technology is that it's so unpredictable you have no clue how it will be adopted until it comes out. Tablets were a thing for 15 years before the iPad came out, but nobody used them...what if Apple had decided not to develop the iPad because people didn't use tablets? It doesn't have to be the best or most efficient option either...if that were the cause, people would have used Beta-maxes instead of VCRs. Besides the fact that it does actually work on some level (and I'm sure will improve in time), it's inspirational...it inspired people to donate over $2 million to the project.

Also, in looking for the Indiegogo page, I discovered another company that's working on something similar. This product doesn't have the smart road capabilities apparently, but is much thinner and can be placed on top of existing roads without having to tear them out first. At least according to one article I ran across, France is considering applying this technology to 1000km of roadway.

All I'm saying is that I think that good is going to come out of this...it's obviously something that fascinates and inspires people, and at the very least gets people interested about solar power. And you know, we don't know that the problems surrounding it won't be overcome in the future...there's no reason not to at least try. It's not like we can only research a single avenue involving solar power.

This is me having faith in technology...or at least this particular technology.

Just so you guys know... the test run was an utter failure.

From what I gather, most of the 'failures' listed are either due to the carelessness of the people behind it or the fact that the application of this technology is new and thus either difficult, expensive, or not as efficient as other applications. A test is supposed to root out the problems with something...initial tests are supposed to have problems. Hopefully they'll learn from this, be a bit more time-conscious and careful in their future installations, and redesign where they can.

And to address the last point the video makes, why can't we do both roads and roofs?

From what I gather, most of the 'failures' listed are either due to the carelessness of the people behind it or the fact that the application of this technology is new and thus either difficult, expensive, or not as efficient as other applications. A test is supposed to root out the problems with something...initial tests are supposed to have problems. Hopefully they'll learn from this, be a bit more time-conscious and careful in their future installations, and redesign where they can.

The main thing that I was disappointed in is that the supposed "test" isn't even functional. It's really shameful that these people are supposedly trying to solve the world's energy problem when they're taking millions of dollars and not even showing real results from them.

And to address the last point the video makes, why can't we do both roads and roofs?

If you use the money you would be spending on even more roofs, then you'd have more energy production than would be achieved on these roads.

I agree that it's disappointing that they were so careless about the rollout of their first public test, but I think that reflects more on the company than the technology. I like Solar Roadways in particular because their application is the most audacious, but that also means that it's going to have the most work to do and the most problems to solve. I'm glad that they're going to replace the bad panels, but I'm also hoping they learn from this experience and improve their future rollouts. Apparently the next rollouts are somewhere in Missouri and in Baltimore.

If you put them on the roofs and the roads, you have more energy production combined.

I agree that it's disappointing that they were so careless about the rollout of their first public test, but I think that reflects more on the company than the technology. I like Solar Roadways in particular because their application is the most audacious, but that also means that it's going to have the most work to do and the most problems to solve. I'm glad that they're going to replace the bad panels, but I'm also hoping they learn from this experience and improve their future rollouts. Apparently the next rollouts are somewhere in Missouri and in Baltimore.

If you put them on the roofs and the roads, you have more energy production combined.

Yeah but on the short term, there are still so many roofs to fill that it'd make sense to prioritize that. I'm not saying solar roads aren't inconceivable, but I don't see them being useful in the foreseeable future.

Technology isn't adopted based on what makes sense...if that were the case we'd just be retiring the good ole Betamax.

Yes, technology is applied on what works. Solar Roadways don't really work. Thunderf00t has some decent videos on WHY they aren't a good idea.

Here are most of the videos that Thunderf00t has done on this topic. Ordered in upload date from the newest to oldest.

Videos

Call me a negative nancy if you want, some ideas are actually just terrible ideas. This is one of them... technology has to overcome its practical drawbacks before it can be viable.

Apparently SolaRoad made a solar road in the Netherlands, which had the same list of concerns. They made a solar road (for bikes), and while the results were better than expected (70kWh per square meter), they are abysmal compared to rooftop installations. They produced half the output per square meter, and cost 3-4x more.
This implies that for the same money, and never forget money is a limited resources, you could lay 3-4x more square meters of rooftop installations that would output 2x the wattage. This means that for the same money you could get 6-8x more watts out of a rooftop installation.

And that was for BIKES to ride on, which produce much much less wear and tear on the road than cars do. The coating of the entire road had to be replaced in less than a year.. I have yet to see a convincing answer to any of the practical problems with this technology...

You say we could put solar panels on the roads and the roofs.. that argument works as soon as all the roofs are covered. The data collected so far implies that before that, you're just throwing money away that could be better spent on solar subsidies for rooftop installations.

https://en.wikipedia.org/wiki/SolaRoad