Author Topic: EEVblog #632 - Solar Roadways Are BULLSHIT!  (Read 292933 times)

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Offline gildasd

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1100 on: March 29, 2017, 05:56:26 am »
Does it matter?
On one hand you have bugger all production, on the other there's bugger all production + piss poor performance.

Yeah, not really, just wanted to get it right. I could run typical numbers for those LEDs anyway.
Looks like someone allready did the numbers and came to a factual conclusion:
http://youtube.com/watch?v=63UlBsdElsY
I'm electronically illiterate
 

Offline Delta

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1101 on: March 29, 2017, 02:21:10 pm »


Don't forget the heating elements!  If those figures are indeed gross (shurely not!?) then feck me, when you factor in using grid electricity to melt snow and ice..... This thing is an environmental abomination.
 

Offline Barny

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1102 on: March 29, 2017, 02:55:52 pm »
Are there heating elements?
Aren't the LED's pumping out enough heat to fry them self?
(Probably the reason for the pattern cycling.)
 
 

Offline ataradov

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1103 on: March 29, 2017, 03:41:49 pm »
Are there heating elements?
Aren't the LED's pumping out enough heat to fry them self?
There must be. 99% of the actual roadways surface area is not painted, so those LEDs will be off all the time. Only tiles on intersection and between the lanes will indicate road markings, most of the time in a static pattern. This is not enough to melt snow.
Alex
 

Offline Domagoj T

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1104 on: March 29, 2017, 04:05:10 pm »
When they initially installed the setup they said it was an early prototype and didn't contain the heating elements and solar panels (or at least working ones). They also said that they would install fully functional solar and heating hexagons as a replacement installation later on. The ones installed at this moment are supposed to be that second generation.

The performance during the snowy period a few weeks ago would suggest they indeed have heating elements (or the LEDs are dissipating astonishingly huge amounts of heat for something that is supposed to be eco friendly).
Go green or burst in flames trying?
 

Offline james_s

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1105 on: March 29, 2017, 05:52:36 pm »
As a solar powered art installation the sidewalk tiles would actually be pretty cool, and reasonably feasible. Forget trying to harvest any useful energy from it, just make them self contained and light up. It seems however that they can't even make that work reliably without requiring external energy and that's nowhere near the challenge of making it work as a roadway surface.
 

Offline Domagoj T

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1106 on: March 29, 2017, 06:10:58 pm »
As a solar powered art installation the sidewalk tiles would actually be pretty cool, and reasonably feasible. Forget trying to harvest any useful energy from it, just make them self contained and light up. It seems however that they can't even make that work reliably without requiring external energy and that's nowhere near the challenge of making it work as a roadway surface.
Not only feasible but done before.
https://en.wikipedia.org/wiki/Monument_to_the_Sun
This thing actually produces some excess energy, although it's debatable whether it's economical.
 

Offline james_s

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1107 on: March 29, 2017, 08:09:03 pm »
That's pretty cool. The thing about art is that it doesn't have to pretend to be economical, I've seen far more money wasted on "art" that didn't do anything at all. That looks like a really nicely landscaped park.
 

Offline ataradov

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1108 on: March 30, 2017, 02:02:45 am »
Hey, we've got some road markings! And just as expected, they look like garbage.
« Last Edit: March 30, 2017, 02:07:33 am by ataradov »
Alex
 

Offline LabSpokane

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1109 on: March 30, 2017, 02:16:00 am »
Hey, we've got some road markings! And just as expected, they look like garbage.

And SR clearly have gamed the power generation data by using the inverter data instead of the net metering data provided by the utility. The inverters are on a different bus than the power supplies, so what power generation we are seeing is gross, not net.

At least we now have an initial read on how insanely poor an idea this is. PVWatt predicts about 3.5kWh of generation per day for a 1320W system flat on the ground for the month of March. SR's best day thus far is 0.75 kWh. So we have a solar system that is fantastically more expensive than rooftop solar and produces 20% of the output of a commercial solar panel in the same configuration (laid flat). And it won't even produce that once one factors in the huge parasitic loads of the lighting and heating loads.

I'm sure glad no one saw this coming.

ETA: If the panels were properly angled toward the South at approximately 45 deg, there would be an additional 15% output in energy according to PVWatt. So 20% of commercial panel output sinks somewhere to around 17%.
« Last Edit: March 30, 2017, 05:54:28 am by LabSpokane »
 

Offline Nobody2

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1110 on: March 30, 2017, 01:07:08 pm »
Are there heating elements?
Aren't the LED's pumping out enough heat to fry them self?
(Probably the reason for the pattern cycling.)
They might not need separate heating elements. If the LEDs don't produce enough waste heat, you should be able use the solar cells themselves as heaters. Of course you can't produce energy if you do that, but if your aim is to melt snow laying on top, that's hardly going to be an issue.
 

Offline Delta

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1111 on: March 30, 2017, 01:13:31 pm »
LabSpokane, how about approaching the local politicians and offering to install PV panels (of equal area) on the roof of that toilet block, along with a grid tie inverter and export meter.  We could crowdfund the cost on here.  Then people would see a massively cheaper installation generating massively more power.  Might even make the enviromentalists realise what a stupid idea SR is...
 

Offline Brumby

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1112 on: March 30, 2017, 01:52:32 pm »
IMHO, that will never get off the ground.  Not while there's any positive press to be garnered from the existing setup.

Politicians will defend their crappiest decisions all the way to the polls.  So as long as there are any political powers in control, they are never going to allow such a contrast.

I'd go so far as to say that if you were to attempt to erect such a system on private property next door (if there is any) where it - and it's metering - would be visible from the SR installation ... that city hall would never approve it.

Further, that if you were to find a way to put it up, they would go out of their way to find a means to have it removed - or, better still - visible, but non-operational.  Even better than having nothing to compare against is to have something - which does less than what the SR system is doing.
 

Offline dunkemhigh

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1113 on: March 30, 2017, 02:49:16 pm »
Quote
a massively cheaper installation generating massively more power

It isn't about the biggest bang for buck. If it just made a small profit (taking into account all costs) it would be a goer even though a roof panel might make a bigger killing. Hell, just breaking even would be something - free traffic signals don't come embedded in roof panels (not usefully, anyway)!

There are many issues here, and generating electricity from solar is just one of them, albeit a fairly major one.
 

Offline SeanB

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1114 on: March 30, 2017, 04:30:02 pm »
Yes, but traffic signals that are only really visible at night, on a dry road are not exactly an improvement over the old fashioned environmentally friendly hot melt paint with a zircon and mica flake reflection surface.  If you want solar powered traffic signals simply do the way the city did here and put up a few solar panels on high lamp poles ( high to get the copper thieves to slow down) with massive Infraset concrete battery boxes to house the inverters and battery banks for them. Then use a pretty standard low cost ( at least on the municipality scale of infrastructure costs) standardised set of LED heads, controller and wiring to provide the signalling.
 

Offline dunkemhigh

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1115 on: March 30, 2017, 04:38:58 pm »
The point is that you have to treat it as a whole. Take a smartphone of, say, four years ago and you could level the same sort of thing at it: the camera was much worse than a real camera, GPS not as good as a real satnav, etc. But no-one ever bought a phone JUST to be a camera, or satnav, or web browser, and the whole was better than the sum of the parts.
 

Offline moz

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1116 on: March 30, 2017, 09:01:23 pm »
The point is that you have to treat it as a whole. ...  the whole was better than the sum of the parts.

Roads are a little bit different to smartphones, though. We get much more excited when smartphones kill people, for example. There's roads that have been on fire for decades and the novelty has pretty much worn off, but when a few smartphones catch fire it makes headlines around the world.

A lot of work goes into engineering roads to kill fewer people. They work on the surfaces, the markings, gradients, hundreds of things. So when you imply "the markings won't be visible during the day but that won't matter much"... I dunno, but I'm pretty sure there's been research published on that topic.

Whaddayano, there is. Research report 423 Effectiveness of transverse road markings on reducing vehicle speeds... I suspect that means there are another 422 of them leading up to #423. Or Effectiveness of acoustic road markings in reducing deer-vehicle collisions. More importantly, there's a whole page of references at the US Dept of Transport specifically on the effectiveness of road markings. I kinda get the impression that this is important.
« Last Edit: March 30, 2017, 09:04:13 pm by moz »
 

Offline LabSpokane

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1117 on: March 30, 2017, 10:02:48 pm »
LabSpokane, how about approaching the local politicians and offering to install PV panels (of equal area) on the roof of that toilet block, along with a grid tie inverter and export meter.  We could crowdfund the cost on here.  Then people would see a massively cheaper installation generating massively more power.  Might even make the enviromentalists realise what a stupid idea SR is...

Sorry to say, it's pointless on many levels. No one needed to do a test installation to demonstrate what we already knew from the math.  *NOT* building a solar roadway is the whole point of studying science and engineering.  The math tells you it's a shit idea from the get-go.  This whole thing never should have made it past the numbers-on-the-slightly-dampened-cocktail-napkin design phase.

Any details I've provided beyond this are to illustrate that shit engineering begat shit design which begat fire. 

I have no special knowledge on solar design.  This is well-trodden ground and has been so for the last 40 years. All the data and design techiques are readily available for the googling. The only major change has been the price per watt of solar. For anyone to introduce a photovoltaic power generation scheme that is orders of magnitude more than what is available today is simply stupid.  And until every rooftop, parking lot and vacant piece of land with no other practical use is covered in solar panels, solar roadways will remain completely, utterly stupid and worthless.  It is a waste of society's time, money, and natural resources.
« Last Edit: March 30, 2017, 10:10:27 pm by LabSpokane »
 
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Offline moz

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1118 on: March 30, 2017, 10:24:51 pm »
until every rooftop, parking lot and vacant piece of land with no other practical use is covered in solar panels

People might want to look at the crazy "how much area of solar panels would we need to replace all other electrical generation" maps. You have to actually look for the little dots. And when idiots say "but they leave gaps between the panels"... yeah, so three little dots instead of one... the conclusion is the same. This is not "pave Texas with PV" it's "pave Washington DC".

http://fusion.net/story/129075/elon-musk-reminded-everyone-last-night-how-little-land-would-be-needed-to-power-the-u-s-with-solar/

https://offgridworld.com/how-much-land-would-it-take-to-power-the-usa-with-solar-energy/
« Last Edit: March 30, 2017, 10:27:55 pm by moz »
 

Offline Fungus

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1119 on: March 31, 2017, 09:04:00 am »
For anyone to introduce a photovoltaic power generation scheme that is orders of magnitude more than what is available today is simply stupid.

We're already at about 30% efficiency for solar panels. No possible photovoltaic power generation scheme can even be a single order of magnitude better than what we have today.

This is what needs explaining to the people - solar panels are not going to improve at the speed of cellphones or any of the other magic technology the engineers have given them.

(the same engineers who apparently know nothing at all whenever they disagree with their personal opinions)
« Last Edit: March 31, 2017, 09:05:37 am by Fungus »
 

Offline dunkemhigh

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1120 on: March 31, 2017, 02:47:56 pm »
Quote
So when you imply "the markings won't be visible during the day but that won't matter much"

Wait - where did I say or imply that? Don't put words onto my keyboard and then argue them as if I'd written them.
 

Offline LabSpokane

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1121 on: March 31, 2017, 04:39:39 pm »
For anyone to introduce a photovoltaic power generation scheme that is orders of magnitude more than what is available today is simply stupid.

We're already at about 30% efficiency for solar panels. No possible photovoltaic power generation scheme can even be a single order of magnitude better than what we have today.

This is what needs explaining to the people - solar panels are not going to improve at the speed of cellphones or any of the other magic technology the engineers have given them.

(the same engineers who apparently know nothing at all whenever they disagree with their personal opinions)

I was referring to cost in that paragraph.  Cell efficiency has a ceiling set by physics.
« Last Edit: March 31, 2017, 04:41:32 pm by LabSpokane »
 

Offline moz

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1122 on: April 02, 2017, 10:11:42 pm »
Quote
So when you imply "the markings won't be visible during the day but that won't matter much"

Wait - where did I say or imply that? Don't put words onto my keyboard and then argue them as if I'd written them.

You said, and I quote:

Quote
The point is that you have to treat it as a whole. Take a smartphone ... the camera was much worse than a real camera, GPS not as good as a real satnav, etc. But no-one ever bought a phone JUST to be a camera

So I thought, he's talking about solar roadways. So he must mean "the markings aren't as good as proper markings, the surface is not as good as a normal road surface, the camber isn't as good as normal road camber etc".

Is that an unfair view of what you meant?

At the very least, putting normal road marking paint on a solar roadway is going to seriously compromise the hexes that get painted. To get even the little power that they're capable of putting out they will need to use LED's instead of paint. That is to say: the markings won't be visible during the day.
« Last Edit: April 02, 2017, 10:14:36 pm by moz »
 

Offline dunkemhigh

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1123 on: April 02, 2017, 11:26:11 pm »
Quote
So I thought ...

You thought, and assumed, wrongly, then.
 

Offline Mr.B

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #1124 on: April 04, 2017, 03:32:48 am »
And the ignorant media are still backing this dead horse...
http://www.bonnercountydailybee.com/front_page_slider/20170402/solar_roadways_shining_with_success

The article should be dated April 1st....
Time is the overseer of all things.
 
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