World’s First Solar Road Opens In France

Megalith

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Solar roads seem like a pretty cool idea, but with their so-so efficiency, who knows if they have any real future. Plus, this road is only 1 km and cost over 5 million dollars.

The world's first solar highway has been opened in France, in the not-very-sunny village of Tourouvre au Perche in Normandy. The roadway is just one kilometre (0.6mi) long, but that still works out at 2,800 square metres of photovoltaic cells—enough, hopefully, to power the village's street lights. The road was built by Colas, a large Anglo-French construction company. Colas has apparently been working on its own solar road tech, called Wattway, for at least five years. Wattway has been tested in car parks, but this is the first time it has been used on an active road. There will now be a two-year test period, to see if Wattway can withstand the rigour of being pounded by thousands of cars and trucks per day, and whether it can actually provide a useful amount of electricity.
 
Solar roads make absolutely no sense.

There are so many places to put solar panels that don't have several thousand lb objects eroding their surface and blocking the light hitting them. And you can do it much more cheaply.
 
What happens to the road when a couple of vehicles crash or when tires blow and shred?
 
First set of winter chains will chew through that.

Ugh...we are like kids with new, unknown things. Put in in our mouths or up our nose until we actually figure it out.
 
Terrible idea. A better idea would be to plaster the roof of every building first.
 
This technology has been viable for several years now. I've seen a US engineering company that designed a similar system that seemed to be more robust than this. http://www.solarroadways.com/
Solar Roadways might even be worse, they can't even get it successfully working with a small patch of panels in a sidewalk. They need to work on making solar panels cheaper and putting them places that make even the slightest bit of sense before they try to make roads and walkways out of them.
 
I'm a big fan of investing in improving solar power and (more importantly) power storage. I just don't know about using the surface of something that routinely gets covered with cars to gather power, you know, from the sky.
 
First set of winter chains will chew through that.

Ugh...we are like kids with new, unknown things. Put in in our mouths or up our nose until we actually figure it out.

Yea, just because you can, does not mean you should.
 
even if it's inefficient and it ends up being more robust than asphalt roads i'll take it because out here the asphalt roads are worthless as hell and have to be completely replaced every year.

Why not put the solar panels, hear me out now, on the SIDE of the road???

takes up to much space. i mean lets put it into perspective since this was just the first city i looked up.. los angeles has over 6500 miles of roads that are in basically constant sunlight almost 10-12 hours a day year around. thats a crap load of potential energy just sitting there. if these solar roads end up being as good or better than asphalt/concrete roads why not use them?


First set of winter chains will chew through that.

Ugh...we are like kids with new, unknown things. Put in in our mouths or up our nose until we actually figure it out.

ok so don't put them on highways going across mountain passes, lol.. most cities don't even allow chains or studded tires to be used within them. i'd actually be more worried about snow plows then anything else but i mean i guess you could put a heating source in them so they automatically melt the snow on them.
 
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It sounds like a poor idea to me... I hope they've considered the many issues and still felt confident and not that they got some clean energy funding and decided to build it anyways...
 
ok so don't put them on highways going across mountain passes, lol.. most cities don't even allow chains or studded tires to be used within them. i'd actually be more worried about snow plows then anything else but i mean i guess you could put a heating source in them so they automatically melt the snow on them.

If they can pull energy from sunlight, they should be able to use that energy to heat a coil to keep them from freezing over, which would make snowplows less necessary and drainage maintenance more necessary. But really I think these are a brilliant idea, however i thought they were thinking of using LCD-esque technology that involved the weight of cars rolling over crystals to produce chemical energy....or that was another one of those "wacky ideas" that Star Trek used to have about personal communicators or something....personal communicators, pfeh, as IF.
 
ok so don't put them on highways going across mountain passes, lol.. most cities don't even allow chains or studded tires to be used within them. i'd actually be more worried about snow plows then anything else but i mean i guess you could put a heating source in them so they automatically melt the snow on them.

By "most countries" I guess you mean those within which you live. :)

A large number of countries where snow and ice are constant winter issues allow them. An inch of snow that lasts for a few hours wouldn't qualify but I was extrapolating on the idea of panels on roads in a more general way, as a broad practice.
 
The one thing we can't criticize them for is the cost of $5 million per kilometer. Multiply by 1.6 to get $8 million per mile which is really average by American standards for a road: (generic 2013 estimates, click on "How Much Does It Cost To Build a Mile of Road?", location may vary cost upwards)

  • Construct a new 2-lane undivided road – about $2 million to $3 million per mile in rural areas, about $3 million to $5 million in urban areas.
  • Construct a new 4-lane highway — $4 million to $6 million per mile in rural and suburban areas, $8 million to $10 million per mile in urban areas.
  • Construct a new 6-lane Interstate highway – about $7 million per mile in rural areas, $11 million or more per mile in urban areas
 
Why not put the solar panels, hear me out now, on the SIDE of the road???
Because it's a test run. It's also, I suspect, why they did 1/2 of the road. By doing that, they can directly compare durability with the other side, which looks like it was recently resurfaced.

"Wattway has been tested in car parks, but this is the first time it has been used on an active road. There will now be a two-year test period, to see if Wattway can withstand the rigour of being pounded by thousands of cars and trucks per day, and whether it can actually provide a useful amount of electricity."
 
even if it's inefficient and it ends up being more robust than asphalt roads i'll take it because out here the asphalt roads are worthless as hell and have to be completely replaced every year.



takes up to much space. i mean lets put it into perspective since this was just the first city i looked up.. los angeles has over 6500 miles of roads that are in basically constant sunlight almost 10-12 hours a day year around. thats a crap load of potential energy just sitting there. if these solar roads end up being as good or better than asphalt/concrete roads why not use them?




ok so don't put them on highways going across mountain passes, lol.. most cities don't even allow chains or studded tires to be used within them. i'd actually be more worried about snow plows then anything else but i mean i guess you could put a heating source in them so they automatically melt the snow on them.

You know what else Los Angeles has besides 6,500 miles of road? Tens of thousands of buildings with rooftops that won't ever have vehicles weighing thousands of pounds driving or parking over them.

Even if you ignore the durability problems, or even how drivable the things may or may not be, they're still a terrible idea. LA is also known for lots of traffic. So yeah, there may be 6,500 miles of road that actually is exposed to sun 10-12 hours a day, but it's also covered with cars, dirt, oil, etc. You know when LA's roadways would be free'd up so panels embedded in them wouldn't have the sun blocked due to traffic? NIGHT. This is of course also ignoring the efficiency losses over time as the solar road surface is ground down since it's not like cars drive over roads with cotton balls for tires, so the surface isn't going to remain polished and easily capable of transmitting light. Then you've got the issue of ground glass building up along roadways, because that'd be just amazing for the environment, and we all know that LA is well known for it's cleanliness. I'm not saying the population of LA would all end up with silicosis, but use some sense.

And you're right, asphalt roads do need regular maintenance. That costs a hell of a lot less than replacing solar panels, is easier than replacing solar panels, and when it doesn't get done when it should(which Los Angeles and most urban areas in California are notorious for), it doesn't result in a massive investment that is no longer producing power. The roadway construction cost is also an issue, since yes building entirely new roads is already expensive anyway, but that's rarely ever done in areas that generally have some of the highest power consumption. Move those roads out into the sticks with less traffic? You've got municipalities that aren't going to be able to afford the installation or upkeep(which is why those places don't have huge road networks to begin with, but they do generally have lots of unused land).
 
The one thing we can't criticize them for is the cost of $5 million per kilometer. Multiply by 1.6 to get $8 million per mile which is really average by American standards for a road: (generic 2013 estimates, click on "How Much Does It Cost To Build a Mile of Road?", location may vary cost upwards)

  • Construct a new 2-lane undivided road – about $2 million to $3 million per mile in rural areas, about $3 million to $5 million in urban areas.
  • Construct a new 4-lane highway — $4 million to $6 million per mile in rural and suburban areas, $8 million to $10 million per mile in urban areas.
  • Construct a new 6-lane Interstate highway – about $7 million per mile in rural areas, $11 million or more per mile in urban areas

You're...a little off. It's $5 million Euro, which is ~$5.2 million US, or ~$8.3 million a mile...for a single lane. As best I can determine, this isn't even the cost to "build" the road, it's the cost to cover a pre-existing road with their panels.
 
Because it's a test run. It's also, I suspect, why they did 1/2 of the road. By doing that, they can directly compare durability with the other side, which looks like it was recently resurfaced.

"Wattway has been tested in car parks, but this is the first time it has been used on an active road. There will now be a two-year test period, to see if Wattway can withstand the rigour of being pounded by thousands of cars and trucks per day, and whether it can actually provide a useful amount of electricity."
Woosh?
 
I think making it into the road is a good idea, the only question is if the technology is there yet. It's not like they are throwing down glass-plated panels that would have otherwise went on a roof. These are durable plastic modules. That being said... A lot of posters here bring up some very valid points:

It has to be strong enough to carry the weight
It can't shred or otherwise degrade significantly when the inevitable blowout, snow studs, or something else grinds down on it
It can't present a more unsafe surface for inclement driving than existing concrete/asphalt (when it rains/snows/etc)
It can't deform, soften, or otherwise present a significant additional hazard when it gets hot (direct sun in the summer is the obvious, but also an accident and car fire)
There need to be safe electrical disconnects available for if/when there is an accident for emergency services

And there's the obvious point that it should have some financial benefit. Spending 3x the per-mile cost for road construction get a pathetic amount of energy out of it won't be a sustainable model.

Yes, putting panels on the side of the road would be less expensive - but your already using the real estate for the road, if you line it with panels on the side, your increasing the land requirement for the roadway, or adding additional structure and then your fighting with city councils about potential unsightly looks, safety, visibility, etc.

The idea is to put to use some area that is already being used for another function - this is why solar has invested so much in going onto your roof - it would be a lot cheaper to put it down on the yard on a few poles (and in some places that is done), but your roof is already there being used for something else, and it presents a good structure for installation. Sufficent rooftop installs have brought the cost of engineering and material for roof installations way down, and now are competitive with ground mounted installations for residential. Roadways could be similar story.

Yes, traffic will diminish kWh output, but so do things like clouds, shadows, dust, bird crap, etc. Obviously it would be significantly less effective on extremely highly trafficed roadways, but that goes back to the ROI for installation, and most roads, the traffic is pretty minimal compared to the total surface area of the roadway that is concrete/asphalt. And maybe it could be that it's more attractive along the shoulder (which is extremely low trafficed, and still paved in a lot of areas) rather than the traffic lanes.

I seem to recall some areas in that were using parking lots for solar thermal heating - basically a large blacktoped parking lots with hot water pipes embedded in the asphalt. Solar thermal can be used in a variety of ways, including electric generation, and may make more sense than PV solar in a lot of areas.
 
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it seems like a lot of you think that the $5 million is what it will always cost to install. it is not

This is R&D. There is no mass production cost savings in place yet. Once the Economies of Scale (EOS) kick in - if these are beneficial - then this will be much cheaper. Probably more than asphalt (until oil goes up in price again). Over time, electricity produced could make these cost less. Some panels, like Solar Roadways, have heating elements too which can melt snow/ice cutting the cost of plowing / crashes in the winter.


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EEVblog pretty much thrashed the whole Solar FREAKIN' roadway thing.

https://www.youtube.com/results?search_query=solar+roadways+eevblog

Be careful, EEVBlog has had it out for Solar Roadways since its beginning. People (including this EEVblog blowhard) need to realize this is all R&D. Solar roadways figures of 13 trillion (I think was the number) to repave the entire united states with solar panels is based off of 10 year old prices and pre-EOS. Did the first instillation go poorly for Solar roadways? Yes. Is this indicative of the final product? It's yet to be seen. There were problems in the final steps of the production cycle which they are working to resolve and reinstall the panels.

In the end, asphalt will not be viable forever - it's oil based. A replacement needs to be found and if it can produce electricity or in some other way be beneficial beyond just being a transit way then all the better.

Since I do think EEVBlog is totally biased toward hating Solar Roadway I'll include Solar Roadway's equally biased opinion on the matter: http://solarroadways.com/Blog/Show?b=4

I will be honest, I hope solar paneled roads of any kind/company do come to pass as I do think there's a huge upside to this approach.
 
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Well, duh, this is brilliant! (pun)

The "solar roadway" (what a horrible appellation) can make electricity at NIGHT! All those headlights from all those cars... If there are a lot of pile ups, that'll help, too. Any post-crash fire will also make electricity! Win, win!

So, who pays for this and who gets the money that gets taken to pay for it?
 
They can't even maintain the roads they have now, let alone with these add ons.
 
They can't even maintain the roads they have now, let alone with these add ons.
Watch out, you'll offend someone by bashing the idea of putting solar panels on roads instead of the thousands of acres of rooftops in any city where they'd be far easier to install and maintain, not to mention actually produce power since most of their surface area won't be perpetually covered by vehicles anywhere except a countryside village.
 
Watch out, you'll offend someone by bashing the idea of putting solar panels on roads instead of the thousands of acres of rooftops in any city where they'd be far easier to install and maintain, not to mention actually produce power since most of their surface area won't be perpetually covered by vehicles anywhere except a countryside village.

Not to mention maintenance would be expensive one can only assume. Pavement and concrete which are stronger break down fast enough, solar panels I can only assume would be way worse and be broken most of the time.

Roofs one would assume deal with much less wear and tear...
 
Not to mention maintenance would be expensive one can only assume. Pavement and concrete which are stronger break down fast enough, solar panels I can only assume would be way worse and be broken most of the time.

Roofs one would assume deal with much less wear and tear...
Indeed. I did mention that(although not quite as specifically) in my previous post. The whole thing about this just being the R&D phase is utterly absurd, because if we can't cheaply and reliably stick solar panels everywhere else(again, rooftops), why pick one of the least practical locations to ever put the things? Even the idea of putting them in parking lots is silly, because except on the weekends in business parks, parking lots tend to either have lots of vehicles... or they're not that large in the first place. Exceptions to this are of course things like stadiums and amusement parks in the off season, but for all of the solar panels used to pave those parking lots with, they could have been put on rooftops instead. About the only place less practical for solar panels in most circumstances would be the ocean floor.

And sure, getting away from oil would be nice. But that doesn't mean replacing asphalt with solar panels is the logical way to do it, instead of installing those solar panels pretty much anywhere else that would allow for greater and more reliable energy production.
 
Be careful, EEVBlog has had it out for Solar Roadways since its beginning. People (including this EEVblog blowhard) need to realize this is all R&D. Solar roadways figures of 13 trillion (I think was the number) to repave the entire united states with solar panels is based off of 10 year old prices and pre-EOS. Did the first instillation go poorly for Solar roadways? Yes. Is this indicative of the final product? It's yet to be seen. There were problems in the final steps of the production cycle which they are working to resolve and reinstall the panels.

In the end, asphalt will not be viable forever - it's oil based. A replacement needs to be found and if it can produce electricity or in some other way be beneficial beyond just being a transit way then all the better.

Since I do think EEVBlog is totally biased toward hating Solar Roadway I'll include Solar Roadway's equally biased opinion on the matter: http://solarroadways.com/Blog/Show?b=4

I will be honest, I hope solar paneled roads of any kind/company do come to pass as I do think there's a huge upside to this approach.
He's hating on it because it doesn't work, all his hate is based on math. The panel's can't make enough power to light up led's that will be visible in the middle of the day let alone heat up the surface to melt the ice nor pay for themselves by making electricity. Watch his video's and see if his numbers don't add up.
 
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He's hating on it because it doesn't work, all his hate is based on math. The panel's can't make enough power to light up led's that will be visible in the middle of the day let alone heat up the surface to melt the ice nor pay for themselves by making electricity. Watch his video's and see if his numbers don't add up.

Yep & the arguments that advances in technology will increase the road's efficiency can be applied to rooftop solar as well since they use all the same tech. This is about the worst possible application of solar panels, but they'll push on with it anyways & piss a ton of money away.
 
Solar roadways are a construction scam in my opinion. You trick a city into implementing them and not only do you get millions upfront, but exclusive maintenance costs for years too. It'd be brilliant if the fundamental idea actually worked though, but again that doesn't seem to be the goal.
 
This technology has been viable for several years now. I've seen a US engineering company that designed a similar system that seemed to be more robust than this. http://www.solarroadways.com/
That's a scam. They tried those in effect. And they failed within days after installation, and cars didn't even go over them since they put them in a park. They couldn't even produce enough power to illuminate the built in leds, so they worked off external power, and even then the leds were completely invisible until dusk.

There is absolutely no point in putting solar cells under a road, when you can put them on roofs where there are no cars driving over them, and no shade 50% of the day.

The cost of installation would be astronomical, dirt gets on them, rain gets on them snow gets on them, all reducing efficiency. Roads needs to be adhesive therefore they need a rough surface, that further reduces solar penetration.

Even in the most ideal conditions a road installed solar panel couldn'T produce 40% of the power of a roof installed one.

I mean why the fuck would you want to install solar panels in a car park under the cars? Put them over them on a few I beams and voile two birds with one shot. The cars don1t get overheated in the sun, and the solar panels work at full capacity even if the car park is full, and they don't get dirty from cars driving over them either.

This concept is so much bullshit that it makes my head hurt.
 
Watch out, you'll offend someone by bashing the idea of putting solar panels on roads instead of the thousands of acres of rooftops in any city where they'd be far easier to install and maintain, not to mention actually produce power since most of their surface area won't be perpetually covered by vehicles anywhere except a countryside village.
No what's offensive is that a significant percentage of [H] posters are railing against R&D/science. I guess Luddites only like tech if it's already completely developed. Sadly that's not how R&D/science works.
 
I don't care how much R&D you pour into this, the simple fact that you have EVERY SINGLE TIRE applying an abrasive force that scours the surface of the road over time, turning whatever covering material that can transmit light to a solar cell opaque over time simply flies in the face of common sense. It's simply misapplied science. Pour that R&D into making panels ever more efficient, smaller, and lighter. Then get them onto roofs or places where you do not have something driving over them continuously so that they can do what they are designed to do. Solar roads are a rare form of idiocy that is being propagated by hucksters on a gullible, misinformed and ignorant public. I'm 100% for R&D/science, but for god's sake, don't take an idiotic idea and run with it when there are much, much more effective ways to make it happen.
 
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No what's offensive is that a significant percentage of [H] posters are railing against R&D/science. I guess Luddites only like tech if it's already completely developed. Sadly that's not how R&D/science works.
Ah, ok. So we're all luddites because we see that the technology would be better put to use elsewhere. Gotcha.
 
Yea, I'd love to see them succeed, but it would be monumentally cheaper to just put solar awnings in the median or over the roads than to do this... (inmo/afaik)
 
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