EEVblog #632 - Solar Roadways Are BULLSHIT!

[madires]

No sane engineer would come up with the idea of using glass tiles for roadways. That idea is totally braindead! Those glass tiles won't stand dust and traffic for long, they're sanded down, which will also reduce the solar efficiency. What about friction and wear on tires? Add rain for more fun. Glass tiles would be deadly.

[stenor]

It was promptly deleted 

[Legit-Design]

33$/m^2/year  so they are actually claiming maximum of 30 years for these, that comes to around 990$/m^2/lifetime how much solar energy they have produced. If they are going to get roads that pay for itself during the lifetime.... 

real quotes from their site:

How long will these Solar Road Panels last?

We're designing our panels to last a minimum of 20 years. Solar cells are the limiting factor: they can continue to work up to 30 years but they're at the end of their life cycle by then.

Years ago, when we were working on our very first prototype, we estimated that if we could make our 12' x 12' panels for under $10K, then we could break even with asphalt. That was mere speculation and had no relevance to the cost of even our first prototype, let alone our second.

They should make 1 m^2 panels that lasts 300 years. Would almost break even on that $10K price point?

[madires]

It was promptly deleted 

The sad and dangerous thing is, that those people believe in their project. For us it's another scam.

[DaveG]

The biggest problem, apart from the money, would simply be wear, glass isn't that durable.  Friction isn't much of problem as it mainly the physical key of the aggregates that provides the grip, having a textured surface should be able to keep that in check.  But then again the road noise could be hellish.

Also how are these panels anchored, the big test would be a heavily loaded truck doing an emergency stop.

But fundamentally I really want to see a snowplow go over them, would they just shatter, or would the plow catch the edge and create an expensive cascade of glass.

[rob77]

The biggest problem, apart from the money, would simply be wear, glass isn't that durable.  Friction isn't much of problem as it mainly the physical key of the aggregates that provides the grip, having a textured surface should be able to keep that in check.  But then again the road noise could be hellish.

Also how are these panels anchored, the big test would be a heavily loaded truck doing an emergency stop.

But fundamentally I really want to see a snowplow go over them, would they just shatter, or would the plow catch the edge and create an expensive cascade of glass.

i would not like to be in the proximity of a 30tonnes truck during emergency braking on those tiles... that would be a hell of a flying shrapnel around it such a truck during intensive braking is deforming the tarmac/asphalt, so it would shatter those glass tiles for sure.

and the snowplow is a very good point 

[EEVblog]

It was promptly deleted 

LOL!
That says a lot.

[Legit-Design]

But fundamentally I really want to see a snowplow go over them, would they just shatter, or would the plow catch the edge and create an expensive cascade of glass.

and the snowplow is a very good point 

http://solarroadways.com/faq.shtml
They already "fixed" this issue... READ THE FAQ ON THEIR SITE
They installed heating pads in the roads to melt the snow. And:

Here's the worst case scenario: if all else fails, we can replace snow plows with street sweepers where needed (vehicles with large rotating brushes). They're used here in Idaho in the spring to clear the roads of the sand that was used for traction during the winter months.

One could do whole series of videos just from their stupid write offs on how to fix problems.

btw the old video is still listed on twitter. if people want to find it they can find it on their youtube history anyways?

[bitwelder]

Talking about money, also what is going to be the environmental cost of recycling a patch of e.g. 1 Km of 'solar roadway' ?
Surely covered by the 33 USD/sqm*year returns, right?

[rob77]

melting the snow is total bullshit        you would need extreme amount of energy to melt the snow - orders of magnitude higher than the energy produced by the cells . not to mention the shitty efficiency during winter - sun is shining in a really shallow angle during winter, and if it's snowing ... well... the energy output of the cells will be in the zero-range

and regarding the wipes instead of plows.... have they ever tried to wipe a compressed snow ? or will they wipe the roads constantly 24/7  to avoid compression of the snow by the vehicles ?

another point is the SALT - it's common to use road salt to decrease the freezing point of the water and therefore avoid formation of ice on the roads.. how long will those tiles last in such a extremely salty environment during winters ? we all know what is salty water doing with electronics and cables

those solar-roadway guys either never seen a piece of snow or they are literally stupid     

[dexters_lab]

great video Dave,

personally i think they just got carried away with the idea

i wonder though if it could work if it was just used for off-road use, like driveways and parking lots it would simplify things greatly.

[EEVblog]

btw the old video is still listed on twitter. if people want to find it they can find it on their youtube history anyways?

I'll delete it tomorrow.

[EEVblog]

another point is the SALT - it's common to use road salt to decrease the freezing point of the water and therefore avoid formation of ice on the roads.. how long will those tiles last in such a extremely salty environment during winters ? we all know what is salty water doing with electronics and cables

Interesting point. Another one to add to the almost endless list of problems...

[rob77]

great video Dave,

personally i think they just got carried away with the idea

i wonder though if it could work if it was just used for off-road use, like driveways and parking lots it would simplify things greatly.

fully agree, they got carried away with the idea and they lack knowledge in the critical areas of road technology

regarding off-road use - for parking lots it's useless - during daylight those are full of cars - blocking the light.

but we're discussing this topic with the colleagues at work, and one of the colleagues stated "actually it's great ! you could use those tiles with leds and pressure sensors  on playgrounds to build self-powered interactive games for children - children would love those"

or those could be used on public squares/plazas - producing electricity to lit up the public square during night (pumping energy to the grid during day and taking energy from the grid overnight).

so definitely the tiles itself would be useful in many applications, but definitely not for roads or parking lots !

[VK5RC]

On roads people and their cars have accidents, the vehicles are full of FLAMMABLE fuel, with a great ignition source (electricity) just below the surface, to me, is a bad mix, gawd help us if they put a hydrogen car on a solar roadway!
This project is very poor engineering, no you can't call it that; it really is Government support scheme raiding.

[DenzilPenberthy]

As has been mentioned above, it's solving a problem badly that does not exist. there is no shortage of roofs.

As for the melting snow thing - Daylight is turned into heat with almost 100% efficiency but roads still ice over. Derp!

[Artlav]

This project feels a lot like Moller skycar - awesome but impractical, and not even well engineered for what is there.

Come to think about it, a lot of their problems would fly away, no pun intended, if they were to unite forces with  Moller International.

Assuming flying cars, there will be no problems with:
-Surface traction
-Thick glass for carrying weight
-Shading by cars
-LED marker consumption
-Heater consumption
-Inability to tilt the road to follow the sun
-Flammable liquids spilled from wrecks
-Salt for de-icing
-etc

Hmmmm.

[DenzilPenberthy]

I am 100% unconvinced by their claims about surface traction. As a motorcyclist there is no way I would ever ride on a glass road. Even white line paint and man-hole covers are dangerously slippy.

Aside from large oil/diesel spills, little oil drips get absorbed into the tarmac and don't become a problem. On glass they would just build up into an oily film over the whole thing. Lethal.

[george graves]

Ok, ok.  Yea.  You guys LOVE to argue the tech specs of anything... 

BUT....All the technical details aside....I think Dave did a great job at the math.  BUT - to the consumer, he/she will put that aside and just call you a "Hater" - it was totally unconvincing to them - so a great job for nerds!  But to the the backers - that video will fly right over their head.  Hater's gonna hate!

I hope you all take a moment and thing about what the real issue is.....Let's step back and look at the bigger picture.

Science.  Or lack of science in schools.  That's what we are really talking about here.  Aren't we?  That the average politician, average consumer, has no experience of science, or engineering.  No clue how to do basic unit conversions (I didn't see anything in Dave's math that wasn't a factor, or a unit conversion - correct me if I'm wrong - basic stuff)

It's easy for science/engineering minded people like us to look all high and mighty over our friends/co-workers on a topic like this.  (some of you seem to revel in the fact you know more than your non-science friends)  Well, shame on you I say!  Stop patting yourself on the back, and start talking about the need for science in the classroom.  You know, in a non-I-m-smarter-than-you kind of way.

/end rant.

[waspinator]

can't you angle the LEDs towards oncoming traffic to increase their efficiency?

[rob77]

This project feels a lot like Moller skycar - awesome but impractical, and not even well engineered for what is there.

Come to think about it, a lot of their problems would fly away, no pun intended, if they were to unite forces with  Moller International.

Assuming flying cars, there will be no problems with:
-Surface traction
-Thick glass for carrying weight
-Shading by cars
-LED marker consumption
-Heater consumption
-Inability to tilt the road to follow the sun
-Flammable liquids spilled from wrecks
-Salt for de-icing
-etc

Hmmmm.

that would be awesome ! they should definitely cooperate ! (who cares about the fact that you don't need roads for flying cars the government will buy it and that matters !  )

[daqq]

This project feels a lot like Moller skycar - awesome but impractical, and not even well engineered for what is there.

Come to think about it, a lot of their problems would fly away, no pun intended, if they were to unite forces with  Moller International.

Assuming flying cars, there will be no problems with:
-Surface traction
-Thick glass for carrying weight
-Shading by cars
-LED marker consumption
-Heater consumption
-Inability to tilt the road to follow the sun
-Flammable liquids spilled from wrecks
-Salt for de-icing
-etc

Hmmmm.

To hell with cars, I want portals!

[Legit-Design]

can't you angle the LEDs towards oncoming traffic to increase their efficiency?

Sure just install servo motors on them, for every engineering problem there is a solution. 

[w2aew]

Dave's magic marker toss at the very end of the video is a thing of beauty.

He's a consummate professional.

If only the marker stayed on Dave's head at the end - that would've been classic!

[Legit-Design]

Dave's magic marker toss at the very end of the video is a thing of beauty.

He's a consummate professional.

If only the marker stayed on Dave's head at the end - that would've been classic!

This sounds like an engineering problem waiting for a solution. If we can build solar roadways, sure we can get one FRINKIN' marker to stay on one head? It would have some added bonuses... every time Dave scratches is head (I was watching live stream and he scratched his head ALOT while filming solar roadways episode) but anyways everytime he scratches head he would have marker right at his hand. Hmm maybe MAGNETS, and solar panels. Not just any stupid permanent magnets, Dynamic! magnets that change their strenght based on the needs!