Solar pavement

It is my understanding that Wal-Mart installed roof mounted solar panels on some of their stores and they provided enough power to power the store during daylight hours. No need for solar pavers.

I think this couple has a hair-brained scheme but often useful products come out of such proposals.
 
NW-Bound said:
+1 on people who put their thumbs down on this!
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+1.

NW-Bound said:
So, what is the cost? No matter how strong this glass block is, the tiles still have to be laid on top of a substrate. In other words, first build the road then put this on top.
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Right. And when that road gets a crack or a pothole, the panels on top will become little shards of glass all over the place.

I think some people just don't know how hard a road "works", and the difficulty in making a good, long lasting one. When we fly over just about anywhere the only place where activity >is< evident is on paved surfaces--so why put solar panels there? There are tons of better places to put solar panels, places where they can be easily serviced without inconveniencing everyone.

But, the idea is already generating--money from rubes.
 
Schutzie said:
Well now, let's think about this for a minute. ...
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You need to understand, the thinking has already been done. Solar photo-voltaic panels have been around a long time. They are understood and characterized. There is more than 30 years of 'thinking' already, not just minutes. So let's review:


... If one paved say a parking lot with these things, and they generated enough power to provide charging stations for electric cars, that would be a good thing. ...
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We understand that panels with the proper angle to the sun produce more power than panels laying flat in a parking lot. So if these can produce X amount flat, they would produce more than X at the correct angle. There is no more thinking required to realize that this idea wastes some of the potential of the panel. Why charge 10 cars for example, if we could charge 15 cars with the same number of panels?

It is not a good thing to set something up that charges 10 cars when you could charge 15 instead. It's a waste. Waste is bad. So it's a bad idea.


Also, have you given a minutes thought to what the word 'parking lot' means? You park cars there. During the day, when the sun shines. So cars parked there will block the sun, reducing the effectiveness of this bad idea even further. So now it's a bad, bad idea.


... If it turned out that the idea wasn't such a great one after all, because say the panels stopped performing and couldn't be cleaned, or they weren't tough enough, or it turns out people pried them up for whatever, then we'd know. And could probably address the issues. ...

Or we could do a sidewalk (volunteering my own!) we'd get a better idea of how they perform in reality and stand up to traffic. ...
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But there is no reason to 'address the issues' because there is no benefit to begin with. And we already know a flat surface will stay dirtier than an angled surface, we don't need to waste money experimenting.



Refine this really great idea, and start paving roads. Now there's where the big savings will come in.

I mean, we gotta repave roads ever so often anyway, right? So, it's not like we'd be tearing up good roads for questionable improvements. We should know first if the idea works, and second, we retrofit as we repave.
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What basis do you have to say there will be any savings at all? This is the circular argument they use on their site. They just say it's cheaper so let's do it, though they have no numbers, and every reasonable estimate says this material would be FAR more expensive than asphalt (which is a recycled product). Where is this savings?

Their claim of 'savings' from the electricity generated is false logic. You would generate more electricity, cheaper, by placing the panels on rooftops, or by the side of the road. Use that savings (if any) to repave roads if you want. Getting less electricity with a more expensive installation makes no sense.

It's a bad, bad, bad idea. There just is no way to legitimately see any good in this.


... I don't see much downside to this thing. ...
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And I don't see any upside. None at all, except for the two people making money from this scam. Hopefully a way is found to put them in jail.


hpnutty said:
Seems like they found enough fools to the tune of 2.2MM. P.T. Barnum would be proud.
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I just came across that from the videos linked earlier. Wow, $2M in donations from gullible people. Mind boggling.

-ERD50
 
Well now hold on. There are good issues being raised here, but in the end it's all speculation as to whether the idea would work or not.
Repairing a solar road should be easier than a paved road, and if they construct the panels right, including the support surface less often.
The bottom line is, build it somewhere and find out

I won't be even thinking about investing in this-yet-I agree, these two aren't giving up enough details on costs.
 
Schutzie said:
Well now hold on. There are good issues being raised here, but in the end it's all speculation as to whether the idea would work or not. ...
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No, it is not all speculation. It is a fact (geometry anyone?) that a panel laying flat will absorb less solar energy than one angled to the Sun.

It is a fact that a car parked over a solar panel will reduce its output.

It's a fact that an additional covering over a solar panel will reduce its output.

It's a fact that a flat panel will retain more dirt than an angled panel, and dirt blocks light and will reduce its output.



Repairing a solar road should be easier than a paved road, and if they construct the panels right, including the support surface less often.
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Now that is speculation!

How could replacing glass panels with electrical components in them be easier/cheaper then grinding asphalt and redepositing it?

And how do we know it would require replacement less often? Isn't that all speculation, with no basis?


The bottom line is, build it somewhere and find out
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Go ahead, on YOUR dime, not the taxpayer's. Then please report back on your progress.

Did you understand what I wrote? You might as well say the same about all the crazy perpetual motion schemes on the internet, 'well, let's build one and find out!'. I can tell you right now, that putting a battery and a motor on the rear wheels of a car, powered by a generator on the front wheels of a that car will not work. Or putting solar panels in front of the headlights of an EV to recapture the light (both these ideas have been suggested on the Tesla forums). I don't need to build one, because some of us understand the laws of physics, and realize that building one would be a waste of time, and distract from good ideas. Just like this stupid solar road is distracting from potentially good ideas.

I won't be even thinking about investing in this-yet-I agree, these two aren't giving up enough details on costs.
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Details? They have almost nothing on costs, let alone 'details'. I don't know whether to laugh or cry.

-ERD50
 
OK, I can't help myself...

The earlier video did a good job of busting the idea of using panels to melt snow, but they used big, country-wide numbers, and I think that loses perspective. So let's break it down for a one mile stretch of road, a 12' wide lane, per inch of snow. And don't forget, the electricity for this comes from the grid, the panels are covered with snow!

The math conveniently breaks down to 5,280 feet (one mile) times 12 feet wide divided by 1/12 foot deep (one inch) so factors out to 5,280 cubic feet per inch of snow. A cubic foot of snow is typically ~ 15 pounds (water being ~ 62#/cubic foot). So that's 79,200 pounds per inch of snow.

It takes 144 BTUs just to melt a pound of ice. Multiplying and converting BTU to watt/hours, we get...

3,342,747 watt hours per inch of snow per lane/mile. That's 3.343 Mega-Watt Hours or 3,343 Kilo Watt Hours. That is ~ 3x the average electrical consumption of a US household for an entire month, around the clock! For one lane of a one mile stretch of road!

And of course, some heat will be lost to the ground and the air, but I'll be kind and ignore that for now.

At the approximate national average of $0.10/KWh that would be ~ $334 to melt one inch of snow per lane per mile, or about $1000 for a 3" snow!

A snow plow might get 5 mpg, so that's about ~ $1 of fuel per mile? Throw in a couple bucks for the truck amortization ($250,000, useful life of 250,000 miles - roughly?), and a few more bucks per mile for the driver? And let's assume they make 3 passes to clear 3" of snow (generous?) - so, maybe ~ $18/mile for a 3" snow?

Compared to $1,000:confused: And actually much more if you factor in losses to ambient air/ground.

And those of us who actually live in snow country know what happens when snow melts, and then freezes (when the heaters would be turned off). Black Ice!!!! You need to make sure you get rid of any standing water. It would probably take lots of heat to actually evaporate much of that water.

But the people who are promoting this say it is cost effective, so I guess it must be. Right?

Wrong!

Oh, I almost forgot - power outage during a snow-storm? Ever heard of those? I have! :greetings10:

So now we have a community with these fancy, high tech roads, and not enough snow plow equipment to clear them, and a city-wide black out, and no power from these snow covered panels. Sounds like the plot of one of those B-Grade horror flicks!

Snow-mageddon !


OK, bring it on - what are the non-speculative (OK, I'll give you a break, you can speculate a little) possible benefits that could outweigh the negatives?


-ERD50
 
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Another obvious flaw in this scam is that IF glass were somehow cheaper and better to use as a road surface..don't you think it would have already been done?

The very simple fact that no parking lot/highway/road is currently paved with glass means that it's physically not possible and/or cost-ineffective.

And that doesn't even begin to address the previously pointed out issues with the panels being at flat angles, etc.

You would need the road solar panel covering material to already be cost-effective and already be used currently in order for a sub-optimal solar panel positioning in the road to even hope to be close to make any economic sense. The fact that you're taking an idea of a road surface material that can't currently be used, and trying to mesh it with another stupid idea (solar panel at poor angle, among other many issues pointed out by the YouTube video), makes it a stupid idea squared!
 
So, is there any way to bet against this loser of an idea and make some money? What we need is some sort of "Kickstarter-shorting" mechanism whereby people can speculate >against< crazy, unworkable startups that capture the imagination of some people.
Such a thing might serve as a useful market pricing signal to those who believe a particular idea "just can't lose." If 90% of the people are willing to bet against the idea, maybe they'd reconsider their investment.
 
samclem said:
So, is there any way to bet against this loser of an idea and make some money? What we need is some sort of "Kickstarter-shorting" mechanism whereby people can speculate >against< crazy, unworkable startups that capture the imagination of some people.
Such a thing might serve as a useful market pricing signal to those who believe a particular idea "just can't lose." If 90% of the people are willing to bet against the idea, maybe they'd reconsider their investment.
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Yes, please!

If nothing else, it would flush out the serial KickStarter con artists. Yes, that's a real thing. At least there's KickFailure » Some projects just can't be kicked hard enough.
 
Here in AZ, I am waiting to see Walmart, shopping malls, office and medical complexes offering covered parking using solar panels to provide shade. Two birds with one stone. It is practical, easy to maintain, and a lot less expensive than solar pavers. What a scam!

I have seen a local restaurant with such covered parking. The local university has had a solar panel array on the top story of its multi-level parking for a few years. With the price of the panels coming down, I think we will see a lot of this in the future. Panels in parking lots and commercial places are not susceptible to shading by trees and close-knit neighbors like many residential installations.

Somehow, people overlook these lower hanging fruits, and go for the scams like these solar road pavers. But then, some people have been buying "100-mpg carburetors" or gasoline-line magnetizers for decades, so this is not really new.
 
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NW-Bound said:
Somehow, people overlook these lower hanging fruits, and go for the scams like these solar road pavers.
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I'm really surprised at how much money they've been able to raise through kickstarter ($2M). I would have thought that the comments would have been filled with substantive criticisms that we see posted here and that this would have warned people off. However, the comments appear to be mostly positive.
 
photoguy said:
I'm really surprised at how much money they've been able to raise through kickstarter ($2M). I would have thought that the comments would have been filled with substantive criticisms that we see posted here and that this would have warned people off. However, the comments appear to be mostly positive.
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I'm shocked too....but looking at the numbers, assume the average person 'donates' (?) $40. That's just 50,000 people who [-]rely just on 'feel good' feelings to make decisions devoid of facts[/-] thought it sounded like a 'good idea'.

Given the few articles and press it received, and given that many of the 18-35 demographic is on-line, I don't find it too surprising they could find maybe 50,000 rubes to fall for an idea that has absolutely no scientific basis for being a good idea, given the capabilities of existing technology in actual production and use.

And just look at how many BILLIONS of people believe that CO2 emissions have the greatest impact on global climate. They completely ignore the fact that the sun has, in fact, a variable energy output, and don't stop to factor in that something that is as big as the sun could easily vary its output by a mere 0.1%, and it could impact the climate on earth. Hell, look at the mere solar flares that happen with some periodic activity, and how disruptive they are - and that's just a freakin' little itty bitty flare of electrons!

So if billions of people ignore the single biggest climate factor impact (in fact, THE source of our entire climate)....it's certainly not a stretch to find 50,000 of them that would fall for this scheme and pony up $40, say, on average.

In fact, we should start our own crowdfunding idea for the perpetual motion machine:

ZERO emissions!
Requires no fuel once it gets going!
The ultimate Earth-friendly device!

That should get the interest of the 'save the world' types that don't bother to stop and think about science.
 
MooreBonds said:
...

And just look at how many BILLIONS of people believe that CO2 emissions have the greatest impact on global climate. They completely ignore the fact that the sun has, in fact, a variable energy output, and don't stop to factor in that something that is as big as the sun could easily vary its output by a mere 0.1%, and it could impact the climate on earth. Hell, look at the mere solar flares that happen with some periodic activity, and how disruptive they are - and that's just a freakin' little itty bitty flare of electrons!

So if billions of people ignore the single biggest climate factor impact (in fact, THE source of our entire climate)....it's certainly not a stretch to find 50,000 of them that would fall for this scheme and pony up $40, say, on average.

...
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Maybe this could have something to do with the topic? Or are we going somewhere with this?
 
At the risk of unleashing a hurricane of criticism, this thread did get me thinking about roads and energy which got me wondering about road compression from traffic and weather as a source of power. The energy of traffic and the freeze/thaw compression destroys roads. Could we somehow capture it?

Knowing that there is rarely such a thing as an original idea, I did some googling:

robinmeadows.tumblr.com/harvestinggreenenergyfromcars

This seems like a potentially interesting, scalable and maintable idea.

I feel certain someone will tell me why this idea sucks rotten eggs. Please do so without also suggesting I am somehow genetically or educationally deficient or a stooge for some lobby or other...it's just a link to something interesting on a Sunday afternoon, not a manifesto or a request for funding.

Time to take the kids to the pool.
 
Sure is a long thread for what most seem to think is a really bad idea . . . :confused:
 
krotoole said:
. . . this thread did get me thinking about roads and energy which got me wondering about road compression from traffic and weather as a source of power. The energy of traffic and the freeze/thaw compression destroys roads. Could we somehow capture it?
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The quick search I did indicated the existing pilot projects aren't producing much juice. One key fact to know would be whether producing the power reduces the fuel efficiency of the vehicles even a tiny bit. For example, we could imagine a simple treadle or pressure-plate arrangement what would produce power from passing vehicles, but the fact that the car then needs to regain the lost 1/4" of height it lost would swamp any gains from the electricity produced.
I've seen schemes for small wind-turbines along roads to capture the energy from the wake of passing vehicles. Same question: Is there a net gain? Is it worth it?
 
krotoole said:
At the risk of unleashing a hurricane of criticism, this thread did get me thinking about roads and energy which got me wondering about road compression from traffic and weather as a source of power. The energy of traffic and the freeze/thaw compression destroys roads. Could we somehow capture it?

Knowing that there is rarely such a thing as an original idea, I did some googling:

robinmeadows.tumblr.com/harvestinggreenenergyfromcars

This seems like a potentially interesting, scalable and maintable idea.

I feel certain someone will tell me why this idea sucks rotten eggs. Please do so without also suggesting I am somehow genetically or educationally deficient or a stooge for some lobby or other...it's just a link to something interesting on a Sunday afternoon, not a manifesto or a request for funding.

Time to take the kids to the pool.
Click to expand...

I have a minute, so I'll take a stab at it.

It is interesting and it might have some niche applications that make sense. But the law of conservation of energy tells me this can't create any significant power in general.

OK, so the road is compressed when a car/truck goes over it. If we aren't capturing this energy now, it must be turning into heat, right? Are the roads generating significant heat from traffic weight? I doubt it.

But if we capture it, the element has to be moving a little. What allows it to move? The rest of the road would need to be made stiffer, so the element would absorb the movement. Otherwise, the relatively soft asphalt would still just absorb (most of) the energy.

Think of it like this - imagine a spring loaded bike pump. You push it down 6" and the spring returns 6" so you get some work done (pumping air) with each stroke. Now imagine you put a balloon between your fist and the bike pump. You push, but the balloon squishes out the sides, so the pump goes down far less. The asphalt is kind of like that balloon.

The energy is coming from the vehicle. To the degree that the road flexes, it means the vehicle is getting somewhat less mpg. If we capture wasted energy, fine (but I don't think that is practical), but if we actually try to make roads more flexible, to get more energy into these elements, we are just robbing Peter (the vehicles) to pay Paul (the elements). And there will be losses in the conversion, so it is just a lost cause.

That's what they did in the sidewalk example - they are not 'creating' energy - it comes from the people. Walking on soft sand is harder than walking on a firm surface. Maybe it doesn't matter here, but it just isn't a big source of energy, or those people would be working up a sweat. Conservation of energy.

Now, to capture some of this and use it locally so you don't need to run power - that might make sense. But those are niche applications, and just not practical at high power levels.

-ERD50
 
+1 to what Samclem and ERD50 said.

While they were posting, I did my own little investigation and like to share what I have found.

Piezo transducers have been long used as microphones or phono cartridges to convert vibrations into electrical signals. And they have been used as spark generators in cigarette and BBQ igniters. But these are tiny signals. To use them for large-scale electric power generation from road vibrations? Sounds like a harebrained scheme to me, but some articles suggested that some took it very seriously. So, I decided to take a look on the Web to see what has been done.

A Google search revealed several articles describing how an Israeli company called Innowattech in 2008 demonstrated a prototype generator embedded in a road in Israel. Details were sketchy, as some articles said that the test section of the road was 10m, some said 100m. But many repeated the claim that an energy of 2000 Wh was accumulated.

While 2 KWh is a respectable amount of energy, the time to accumulate this amount was not noted. A 200W solar panel costing around $300 retail can accumulate that much energy in 10 hours. Is that section of piezo-road cheaper than that, and can collect the same amount in less time?

Nearly all articles repeat the claim of the company that a 1-km section of the road can generate 400 KW (note that some articles said 400KWh, which is meaningless if the accumulation time was not also noted). That seems awfully high to me.

OK, so 400kW/km is 640 kW/mi. To verify that this is absurdly high compared to my intuition, I did the following simple calculation. All that energy comes from the vehicles. And how much energy are the vehicles expending? A car with an ICE converts most of its energy to heat, so let's take the Tesla which uses about 350Wh per mile.

Energy expended = 350 Wh/mile = 1,260 KJ/mile
At 60 mph, power = 1260 KJ/60 = 21,000 W = 21 KW

Using the 3-sec rule spacing between cars, and ignoring car lengths, we have 20 cars in each lane in the 1-mile length.

Total power expended = 21 KW x 20 = 420 KW/lane.

So, let's assume a 4-lane busy highway, and we still have only 1,680 KW. Of that power, how much is used by the cars to push the air in front and around them, to overcome tire rolling friction, etc..., compared to the power used to "pound" the road? And then, how much of the road compression energy these piezo elements can capture? How are we going to get 640 KW out of the total 1,680 KW?

I am sure many people here also like to see the magic formula people at Innowattech used to come up with their "guesstimate". By the way, I would like to find a truly scientific article by an independent source about the above experiment in 2008. There is also no follow-up project that I could find.


Rustward said:
Sure is a long thread for what most seem to think is a really bad idea . . . :confused:
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But, but, but there are so many bad ideas floating around, more than the engineers among us can shake a stick at.

We are f****** doomed!
 
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Following is a bit more of how common sense will tell you that the 400 kW/mile of road claimed by that Israeli company is all hogwash. I will expound on the post by our friend ERD50 a bit more.

ERD50 said:
It is interesting and it might have some niche applications that make sense. But the law of conservation of energy tells me this can't create any significant power in general.

OK, so the road is compressed when a car/truck goes over it. If we aren't capturing this energy now, it must be turning into heat, right? Are the roads generating significant heat from traffic weight? I doubt it.

But if we capture it, the element has to be moving a little...
Click to expand...

The basic high school physics class taught us that "Energy = Force x Displacement". A rock of 100 tons provides us with no energy if it just sits there. If it drops 10 ft, it now releases the potential energy in that drop. Hydroelectric dams cannot get energy from water sitting in a stagnant lake; they need that water to flow from high to low. Displacement, my friends, we need displacement.

In the case of the cars pounding the road, I am not a civil engineer to know how much the typical asphalt road "sinks" as a car passes over a spot. But my own eyes tell me that the road flexes a lot less than the tires that the car is riding on. So the car tires dissipate a whole lot more energy than the road, because the former flex a whole lot more.

Now, tires do get hot when driven. But how much energy is wasted this way? Common sense tells us that a lot more heat is generated in the tires than in the road, but suppose that they are the same. Then, as the Israeli company claimed that 640 kW would be generated in each mile of the road, then assuming that the piezo generators are 100% efficient, that the highway is 4-lane, that it is busy with cars spaced 3 seconds apart, then there would be 80 cars occupying each mile of highway, and that they will be absorbing the total of 640 kW in their tires, which works out to 2 kW per tire.

2 kW of heating per tire? Darn! I would believe the number if you are driving 60 mph on a flat tire, but normally inflated tires would not be able to take this abuse!

And in my earlier post, these 80 cars were expending a total of 1680 kW to travel at 60 mph, and I do not believe that 640 kW or 38% of that is used to heat up the tires, let alone "heating" up the road by "pounding" it.

PS. Bad ideas are amusing, and really frivolous ones can be annoying. But the ones that truly upset are those that manage to waste public money. But perhaps we should focus the attention on the gullible officials who authorize such waste.
 
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I'm so glad I found this thread. For months I thought my wife and I were the only ones who thought the idea of solar freakin roadways was retarded.


Why be normal when you could just be yourself.
 
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