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The first solar road has turned out to be a disappointing failure

sciencealert.com

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Re: The first solar road has turned out to be a disappointing failure

#241

Post by duck2 »

caymanjim wrote: post #225

This was not at all a failure. They built a 1km experimental road. They gained valuable information about real-world performance and technical challenges. It's not as though they built a 100km long six-lane highway with unproven technology. They built a tiny one-lane trial to test a promising idea. It was overhyped by politicians, but what isn't? Maybe they even steamrolled over engineering red flags. That doesn't me…

If you can deduce something from your current knowledge, you don't need to do an experiment for that. Certainly people knew that putting fragile semiconductors under roads isn't the best idea, but they went on and spent time and money. I would call this a waste.

Re: The first solar road has turned out to be a disappointing failure

#243

Post by asdfasgasdgasdg »

duck2 wrote: post #241
caymanjim wrote: post #225

This was not at all a failure. They built a 1km experimental road. They gained valuable information about real-world performance and technical challenges. It's not as though they built a 100km long six-lane highway with unproven technology. They built a tiny one-lane trial to test a promising idea. It was overhyped by politicians, but what isn't? Maybe they even steamrolled over engineering red flags. That doesn't me…

If you can deduce something from your current knowledge, you don't need to do an experiment for that. Certainly people knew that putting fragile semiconductors under roads isn't the best idea, but they went on and spent time and money. I would call this a waste.

Some people deduced one thing, and others deduced the other thing. There was plenty of excitement about this idea on this very site when it was first proposed. Seeing something once is better than hearing it a hundred times.

Re: The first solar road has turned out to be a disappointing failure

#244

Post by neetdeth »

aniijbod wrote: post #162

Does anyone but me have the suspicion that the animosity towards solar roads was something to do with a 'nerve being touched', some kind of 'triggering'? Sure, they might not work out, but lots of stupid-sounding ideas ('a horseless carriage? Whatever next?') have turned out to work, just as much as lots of somewhat futuristic but nonetheless sensible sounding ideas have turned out not to be here yet ('flying cars ar…

It touched a nerve with engineers because nobody listens to engineers and they’re getting completely sick of it.

Engineers are paid to work things out on paper and determine whether something will work or not. Bridges, airplanes, power distribution systems, those kinds of things. They don’t use arrogance, they use math.

This isn’t particle physics - there are no “unknown unknowns” here that required a real world experiment. The economic infeasibility of solar roadways was an absolute slam dunk case.

So now we have confirmation that it was, in fact a bad idea all along. What’s the reaction? “Well, nobody could have predicted this! We had to try.” No, you didn’t have to waste all that money, you could have just listened to competent people in the first place, who all predicted this.

I mean, excuse the hyperbole, but you may as well applaud the audacity of launching Challenger in temperatures below the booster o-rings’ rated spec. Who knows? It could have worked!

Re: The first solar road has turned out to be a disappointing failure

#245

Post by asdfasgasdgasdg »

egdod wrote: post #229
ars wrote: post #217

Earlier quoted context omitted.

The ground pressure from a truck is around 150 PSI. A woman wearing high heels can match, and even exceed that. So the sidewalk would need to be just as strong as the road.

The woman in heels doesn’t ever slam on her brakes and skid.

That applies sheer stress to the road, but it doesn't really impact the compressive force or pressure applied, right?

Re: The first solar road has turned out to be a disappointing failure

#246

Post by kbutler »

ars wrote: post #217
Wowfunhappy wrote: post #182

Earlier quoted context omitted.

I do wonder if the concept could work on a sidewalk, given that they aren't being perpetually driven over by 3,000+ pound vehicles.

The ground pressure from a truck is around 150 PSI. A woman wearing high heels can match, and even exceed that. So the sidewalk would need to be just as strong as the road.

Common physics example, but it disregards how women actually walk and stand in heels. They walk on their forefoot, rather than balancing their weight on the heel.

https://www.semanticscholar.org/paper/The-higher-the-heel-th...

Shows less than 30 N/cm^2 (40 PSI) for women in heels - and higher heels result in lower heel pressure. Forefoot pressure is higher, despite the larger surface area.

Re: The first solar road has turned out to be a disappointing failure

#247

Post by RadioHacker »

mensetmanusman wrote: post #232
ars wrote: post #217

Earlier quoted context omitted.

The ground pressure from a truck is around 150 PSI. A woman wearing high heels can match, and even exceed that. So the sidewalk would need to be just as strong as the road.

Surprised this is getting down voted, this is a common example in physics 101 describing the concept of point pressure. Architects have to consider the point pressure of heels when designing certain walkways.

I think it's getting downvoted because why does it have to be a _woman_ who's wearing the high heels?

Re: The first solar road has turned out to be a disappointing failure

#248

Post by RadioHacker »

reaperducer wrote: post #134
kolinko wrote: post #120

Earlier quoted context omitted.

You know you kind of described how trains work? :) I just did a quick calculation for Poland - we have 11k km electrified train tracks, with ~1.5m of space between the rails. If I calculated correctly, putting solar panels there would give us ~8-15tWh energy per year, which is 5-10% of the required electricity production for the nation. I've never been a fan of the idea of solar roads, but solar railways might actual…

I don't know how they do it in Poland, but in some countries when you flush a toilet on a passenger train going above a certain speed, the nasty stuff just evacuates to the space between the tracks.

There's an old folksong:

https://lyricstranslate.com/en/oscar-brand-humoresque-passen...

Re: The first solar road has turned out to be a disappointing failure

#249

Post by reitzensteinm »

caymanjim wrote: post #225

This was not at all a failure. They built a 1km experimental road. They gained valuable information about real-world performance and technical challenges. It's not as though they built a 100km long six-lane highway with unproven technology. They built a tiny one-lane trial to test a promising idea. It was overhyped by politicians, but what isn't? Maybe they even steamrolled over engineering red flags. That doesn't me…

The trouble with this viewpoint is that there are an endless number of things we could be trying, and it's more or less a zero sum game.

The idea was terrible on paper, easily falsified by back of the napkin math. The same amount of money could have been spent on, eg, testing the commercial viability of smoothing out grid loads by making ice off peak for cooling.

Re: The first solar road has turned out to be a disappointing failure

#250

Post by HNcantBtrustd »

Mirioron wrote: post #207
tootie wrote: post #42

Earlier quoted context omitted.

I find it hard to believe they were really unaware. They either overestimated the durability of their devices or were running a quasi scam.

I haven't seen anything from it yet that would convince me that it's not a scam. The fact that there are people defending this after all this time baffles me.

I can see this. Marketer can make a video, get investment, and try to deliver.

Engineers herded along by management.

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