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They capture the imagination because there are plenty of places you don’t want to build solar panels. Namely places that you want to leave alone for ecological

by SllX 7y ago

They capture the imagination because there are plenty of places you don’t want to build solar panels. Namely places that you want to leave alone for ecological or recreational purposes. If you can take a piece of infrastructure that is pervasive throughout a built environment and give it additional purpose, then you can save on or reduce the land you specify for this purpose. Does it work? Apparently not, or at least: not yet. We have not successfully accomplished this, but it remains to be seen if this is a case of not yet, or never will. Experimentation yields useful data, even when the experiment is a failure. So where were the failures? The road was less durable than expected. They didn’t account for falling leaves. They didn’t produce as much electricity as they thought it would. Thunderstorms also damaged the road. But! It did produce a decent amount of electricity, it did successfully transmit it, and it did function as a road. Colas has given up and chose not to pursue this route anymore, but it isn’t a death sentence for the idea in its entirety. It is a failure of execution, and there will be a lot of failures before there is ever a success. I’ll end this with the caveat that there might not ever be a success, but it is too early to decide that and further experimentation might yield other interesting road construction technologies.

zzzcpan 7y ago
It's not an experiment that can yield anything or teach us anything if there is no paper and no data. A fraudulent startup maybe.
- avip 7y ago
  There's abundant data. some 2 years worth of daily power generation from road installed PV panels. A ~$5mm experiment, that also resulted in a 1km road. Your local physics department spends x10 that budget yearly, and you can't move your car on the arxiv papers it produces (if any). P.S - Colas is not a startup https://www.colas.com/ https://www.colas.com/
  - zzzcpan 7y ago
    > There's abundant data. some 2 years worth of daily power generation from road installed PC panels I'm not sure how is this relevant. How this data can help engineer proper solar roadways? Where is the data on all the problems they had to solve and problems they couldn't solve?
- SllX 7y ago
  How big is your laboratory? Is it a space you rent out, or is it all the known Universe and all of its history? We’ve been learning things by trial and error a lot longer than we’ve been practicing the Scientific Method. You don’t always get the data you want. You don’t always get someone to summarize the data in a nicely formatted paper published in a respected journal. You get what you get and if not quite like it, make do. If this sort of thing, Solar Roads, doesn’t interest you, that is fine too. Maybe you even have credible reasons to be Anti-Solar Roads. It’s certainly shaky enough ground to start on, but I wouldn’t discredit this road in France as a useful experiment simply because there wasn’t a paper at the end. Thunderstorms and fallen leaves! Maybe they should have known, but they didn’t, and because they didn’t consider that, it’s exciting because now how can we go about addressing the problem if we wish to try this again? Maybe someone can build a road and let it get hit by Thunderstorms just to analyze the rate of fire, so to speak. Maybe someone can build one somewhere else to figure out how it differs from one location to another. Maybe we build a third, and start figuring if a solar road is more likely to attract strikes from a storm than other types of roads? Can we mitigate this with some kind of lightning rod? How many do we need and how spaced apart should they be? Can we capture the energy from the lightning or are they too infrequent even in the vicinity of the solar roads to be worth the bother? A lot of those questions might already be answered or answerable without having to build all of those roads to figure it out, but at the very least, a little roadway in France can spark a lot of questions that are worth answering for anyone trying this anywhere else.
  - zzzcpan 7y ago
    Not how it works. It's not enough to try something, you have to share the knowledge with the community, otherwise there will be no progress until someone else willing to share the knowledge tries the same thing again. So, it's as good as didn't happen if there is no paper and no data (doesn't have to be a peer reviewed paper or anything like that).
  - stephen_g 7y ago
    It’s simply a waste of money if we can do the maths and see that it’s always going to be vastly worse than putting them on roofs, on gantries over roads, or literally almost anywhere else but on a dirty, flat surface with huge pressures on what we already knew were fragile and durable cells. There are several factors, each alone that make this idea a non-starter. All these were known from previous experimental results so this never needed to be done. For example - 1. Placing cells flat reduces the power output by 30% over putting it at an angle and facing north. The angle varies with how far you are from the equator. So putting solar in roads will always yield at least 30% less power than putting it in an appropriate location. 2. Roads are extremely dirty. There’s dirt, brake dust, rubber, etc., not to mention shading from buildings, the natural geography and cars while they are driving over it. This will mean at least another 10-20% less power per solar cell, which will degrade as it gets dirtier. So you’re probably throwing up to 40% of your power away unless you’re cleaning them every week or so. Then factor in damage, etc... a basic engineering assessment shows that it is infeasable, and even with massive improvements, rooftop solar and solar farms will always be correspondingly better. But since you seem to be so big on experimentation, do you want to send me a few million dollars and we’ll put solar on the biggest area of all - the sea floor? Think of how much space there is! I mean, we can calculate that basically no light reaches it, but that’s not important, right? It’ll be valuable data!
takeda 7y ago
The thing is though that currently most roads are made from asphalt, yet even that is not durable enough and needs to be periodically reapplied, how a glass can compete with that?
- CydeWeys 7y ago
  And anyone who lives anywhere it snows knows how badly the roads get beaten up by snow plows and salt.
  - Mirioron 7y ago
    Snow plows and salt aren't even the worst of it. Every road is going to have some water in it and when the temperature drops below zero, that water freezes. Water expands when it freezes and this puts stress on the asphalt. You go through enough of these cycles and your road starts to breaking down.
mikeash 7y ago
What is the advantage of putting the solar panels under the cars rather than above them?
- zdragnar 7y ago
  People drive into things over roads: https://gfycat.com/difficultgrizzledfox https://gfycat.com/difficultgrizzledfox Imagine that, but with solar over the road- you now have sheets of glass shards, live electric wiring and support steel falling down over the road. Additionally, the supports (along side the road to hold it up over the top) become targets for collision as well. The sheer amount of materials required to make it sturdy enough to survive tornados, general high speed winds, and the occasional accident from a moving vehicle means that you're going to have a hard time coming out carbon neutral- or at the very least, you'll lose a lot of the benefits. Of course, putting the panels under the cars is a pretty awful idea as well. Simply put, they don't belong near roads at all.

by SllX 7y ago

zzzcpan 7y ago

It's not an experiment that can yield anything or teach us anything if there is no paper and no data. A fraudulent startup maybe.

avip 7y ago
There's abundant data. some 2 years worth of daily power generation from road installed PV panels. A ~$5mm experiment, that also resulted in a 1km road. Your local physics department spends x10 that budget yearly, and you can't move your car on the arxiv papers it produces (if any). P.S - Colas is not a startup https://www.colas.com/ https://www.colas.com/
- zzzcpan 7y ago
  > There's abundant data. some 2 years worth of daily power generation from road installed PC panels I'm not sure how is this relevant. How this data can help engineer proper solar roadways? Where is the data on all the problems they had to solve and problems they couldn't solve?
SllX 7y ago
How big is your laboratory? Is it a space you rent out, or is it all the known Universe and all of its history? We’ve been learning things by trial and error a lot longer than we’ve been practicing the Scientific Method. You don’t always get the data you want. You don’t always get someone to summarize the data in a nicely formatted paper published in a respected journal. You get what you get and if not quite like it, make do. If this sort of thing, Solar Roads, doesn’t interest you, that is fine too. Maybe you even have credible reasons to be Anti-Solar Roads. It’s certainly shaky enough ground to start on, but I wouldn’t discredit this road in France as a useful experiment simply because there wasn’t a paper at the end. Thunderstorms and fallen leaves! Maybe they should have known, but they didn’t, and because they didn’t consider that, it’s exciting because now how can we go about addressing the problem if we wish to try this again? Maybe someone can build a road and let it get hit by Thunderstorms just to analyze the rate of fire, so to speak. Maybe someone can build one somewhere else to figure out how it differs from one location to another. Maybe we build a third, and start figuring if a solar road is more likely to attract strikes from a storm than other types of roads? Can we mitigate this with some kind of lightning rod? How many do we need and how spaced apart should they be? Can we capture the energy from the lightning or are they too infrequent even in the vicinity of the solar roads to be worth the bother? A lot of those questions might already be answered or answerable without having to build all of those roads to figure it out, but at the very least, a little roadway in France can spark a lot of questions that are worth answering for anyone trying this anywhere else.
- zzzcpan 7y ago
  Not how it works. It's not enough to try something, you have to share the knowledge with the community, otherwise there will be no progress until someone else willing to share the knowledge tries the same thing again. So, it's as good as didn't happen if there is no paper and no data (doesn't have to be a peer reviewed paper or anything like that).
- stephen_g 7y ago
  It’s simply a waste of money if we can do the maths and see that it’s always going to be vastly worse than putting them on roofs, on gantries over roads, or literally almost anywhere else but on a dirty, flat surface with huge pressures on what we already knew were fragile and durable cells. There are several factors, each alone that make this idea a non-starter. All these were known from previous experimental results so this never needed to be done. For example - 1. Placing cells flat reduces the power output by 30% over putting it at an angle and facing north. The angle varies with how far you are from the equator. So putting solar in roads will always yield at least 30% less power than putting it in an appropriate location. 2. Roads are extremely dirty. There’s dirt, brake dust, rubber, etc., not to mention shading from buildings, the natural geography and cars while they are driving over it. This will mean at least another 10-20% less power per solar cell, which will degrade as it gets dirtier. So you’re probably throwing up to 40% of your power away unless you’re cleaning them every week or so. Then factor in damage, etc... a basic engineering assessment shows that it is infeasable, and even with massive improvements, rooftop solar and solar farms will always be correspondingly better. But since you seem to be so big on experimentation, do you want to send me a few million dollars and we’ll put solar on the biggest area of all - the sea floor? Think of how much space there is! I mean, we can calculate that basically no light reaches it, but that’s not important, right? It’ll be valuable data!

takeda 7y ago

The thing is though that currently most roads are made from asphalt, yet even that is not durable enough and needs to be periodically reapplied, how a glass can compete with that?

CydeWeys 7y ago
And anyone who lives anywhere it snows knows how badly the roads get beaten up by snow plows and salt.
- Mirioron 7y ago
  Snow plows and salt aren't even the worst of it. Every road is going to have some water in it and when the temperature drops below zero, that water freezes. Water expands when it freezes and this puts stress on the asphalt. You go through enough of these cycles and your road starts to breaking down.

mikeash 7y ago

What is the advantage of putting the solar panels under the cars rather than above them?

zdragnar 7y ago
People drive into things over roads: https://gfycat.com/difficultgrizzledfox https://gfycat.com/difficultgrizzledfox Imagine that, but with solar over the road- you now have sheets of glass shards, live electric wiring and support steel falling down over the road. Additionally, the supports (along side the road to hold it up over the top) become targets for collision as well. The sheer amount of materials required to make it sturdy enough to survive tornados, general high speed winds, and the occasional accident from a moving vehicle means that you're going to have a hard time coming out carbon neutral- or at the very least, you'll lose a lot of the benefits. Of course, putting the panels under the cars is a pretty awful idea as well. Simply put, they don't belong near roads at all.