Author Topic: EEVblog #632 - Solar Roadways Are BULLSHIT!  (Read 401176 times)

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Offline coppice

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #450 on: June 22, 2016, 02:07:37 am »
...With such a road you dont need heating elements. The power circuits will produce heat which will be consistent, good to melt snow so just by using the heat from energy loss in making electricity you save even more power instead of using energy for a heating element.
You have a huge underestimation of the efficiency power circuits reached in these years, and a bad understanding of the amount of joules you need to melt snow.
And combined: How to melt snow on panels with the unefficiency of circuits that convert no energy because the panels are under that snow?

While snow requires a lot of energy there is one other factor, time. You can melt snow using a low heat output but it will take longer. All those power distribution, power converters and all other components they produce heat so why be wasteful. Think about it this way, this system will be running the whole time, LEDs and power still distributed at night. Snow doesnt come down as 1 big lump, it comes down as flakes. Its only in places that get really really bad snow like the far north where the snowstorm is so thick that you cant see a thing and you get snow coming down onto the road from the slope next to it that you would need heating elements.

But the friction properties of the glass is important because when you melt snow you get water and this can make it slippery and if theres snow on the pavements and the road is angled to help with water dissipation the water could collect and make things worse.
So you don't think there will be a problem with your low heat output being swapped by the cold environment which lead to the water being frozen in the first place? Latent heat works both ways. You need a lot of energy to melt the ice, because the environment had the capacity to suck a lot of energy out of the water and turn it into ice. Perhaps your slow thaw concept is based on waiting for spring?
 

Offline LabSpokane

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #451 on: June 22, 2016, 04:38:43 am »
...With such a road you dont need heating elements. The power circuits will produce heat which will be consistent, good to melt snow so just by using the heat from energy loss in making electricity you save even more power instead of using energy for a heating element.
You have a huge underestimation of the efficiency power circuits reached in these years, and a bad understanding of the amount of joules you need to melt snow.
And combined: How to melt snow on panels with the unefficiency of circuits that convert no energy because the panels are under that snow?

While snow requires a lot of energy there is one other factor, time. You can melt snow using a low heat output but it will take longer. All those power distribution, power converters and all other components they produce heat so why be wasteful. Think about it this way, this system will be running the whole time, LEDs and power still distributed at night. Snow doesnt come down as 1 big lump, it comes down as flakes. Its only in places that get really really bad snow like the far north where the snowstorm is so thick that you cant see a thing and you get snow coming down onto the road from the slope next to it that you would need heating elements.

I'm not sure if you're from the UK or north Idaho, but your 100-level physics needs some remediation. 

There is no "discount" for melting snow on an installment plan.  Also, the thermal losses from the balance of plant equipment are quite small.  The prototype system for Solar Roadways uses Enphase micro inverters, which are 96.5% efficient, which means that 3.5% of the input energy is dissipated as heat.  For a 250W panel running at full output (which a panel in a solar road will NEVER achieve), 8.75W will be dissipated as heat.  In a snowstorm even in daylight, that 8.75W will likely be 1-2W - for a very brief time until the road is covered with snow or brown filth, which is the usual state of the roads when snow melts. 

A 250W solar panel has a surface area of approximately 1m^2, thus you're looking at 1-2W/m^2.  I'm not going to go through all the rest of the calcs, but it is just totally implausible that this low energy density would be remotely near what it would take to melt snow reliably.  The sun strikes the earth at 1 kW/m^2, so even in wintertime, we could reasonably expect 100W/m^2 to strike the ground during the day.  So, why bother building a solar road, when doing nothing would be 100 times as effective and cost nothing?

The reality is that a snow-melting roadway is an energy *sink* not an energy source.  The only way it could possibly work is to pump electricity into the road, and lots of it.  Solar roadways are a complete and utter farce that only serves to separate us from our tax dollars. 
« Last Edit: June 22, 2016, 04:41:29 am by LabSpokane »
 

Offline Fungus

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #452 on: June 22, 2016, 05:36:33 am »
While snow requires a lot of energy there is one other factor, time. You can melt snow using a low heat output but it will take longer.

 :palm:

The total energy is the same so why wait?

The sooner you melt it, the sooner your panels will be generating electricity!
 

Offline Fungus

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #453 on: June 22, 2016, 05:39:30 am »
Quote
“If their version of the future is realistic, if we can make that happen, then roadways can begin paying for themselves,”

It's true!

They can "begin" to pay for themselves. Problem it it will never add up to more than a first installment.


 

Offline System Error Message

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #454 on: June 22, 2016, 07:55:16 am »
Perhaps by paying for themselves even if its not equal or more than invested perhaps it would subsidise instead.

Heres a funny idea, how about we cover the north and south pole with solar panels since during summer at either poles theres always sun. :-DD

Still i'd like to see more solar, unlike a power distribution grid solar power distribution can be localised so power is distributed to local area only.

I remember looking up about roads that have lots of electricity flowing through them to charge electric cars and probably your phone if it has wireless charging  ::)
 

Offline Galenbo

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #455 on: June 22, 2016, 09:26:40 am »
While snow requires a lot of energy there is one other factor, time. You can melt snow using a low heat output but it will take longer.
Are you really that far in physics? congrats.
Unfortunately the factor time comes back if you look at the rise in surface temperature of a box as function of the heat losses inside that box

All those power distribution, power converters and all other components they produce heat so why be wasteful. Think about it this way, this system will be running the whole time, LEDs and power still distributed at night.
Please express yourself in a SI unit, and show the dependence of the most important factors.
For the newbies: what's the heat expressed in joule/watts/... that is lost in those evil converters and leds, when the panels are covered with snow?

I'm absolutely no world wonder, but the age I could still believe this kind of crap must have been under 14y.
« Last Edit: June 22, 2016, 09:28:27 am by Galenbo »
If you try and take a cat apart to see how it works, the first thing you have on your hands is a nonworking cat.
 

Offline EEVblogTopic starter

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #456 on: June 22, 2016, 10:16:54 am »
Still i'd like to see more solar

Everyone would, but putting them on roads is demonstrably stupid idea and always will be for dozens of reasons, not least of which:
https://youtu.be/RjbKYNcmFUw?t=7m51s
 

Offline System Error Message

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #457 on: June 22, 2016, 12:22:16 pm »
Still i'd like to see more solar

Everyone would, but putting them on roads is demonstrably stupid idea and always will be for dozens of reasons, not least of which:
https://youtu.be/RjbKYNcmFUw?t=7m51s


I've been saying that its not a smart idea to make roads out of them, what i mean is rather than spend the money to make solar roads they would be much better off being placed on building surfaces instead and making roofed sidewalks.
 

Offline Wile E. Coyote

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #458 on: June 28, 2016, 07:50:08 pm »
Looks like Route 66 is getting Solar Roadway cancer now.  |O

http://www.architecturaldigest.com/story/iconic-route-66-americas-first-solar-roadway
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Online madires

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #459 on: June 29, 2016, 09:07:50 am »
Ouch! France too, assumably some other system. That's what I'd call embezzlement of tax money (for BS).
 

Offline jp430bb

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #460 on: July 04, 2016, 08:02:04 pm »
Looks like Route 66 is getting Solar Roadway cancer now.  |O

http://www.architecturaldigest.com/story/iconic-route-66-americas-first-solar-roadway

My Missouri tax dollars at work! I'd go check it out, but the install is a 3 hour drive from me. 
 

Offline LabSpokane

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #461 on: July 04, 2016, 09:49:18 pm »
Looks like Route 66 is getting Solar Roadway cancer now.  |O

http://www.architecturaldigest.com/story/iconic-route-66-americas-first-solar-roadway

My Missouri tax dollars at work! I'd go check it out, but the install is a 3 hour drive from me.

You need to do it just for the sake of getting photographic evidence of the ridiculous utility trench they have to build under the road. 
 

Offline coppice

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #462 on: July 05, 2016, 01:53:10 am »
Looks like Route 66 is getting Solar Roadway cancer now.  |O

http://www.architecturaldigest.com/story/iconic-route-66-americas-first-solar-roadway

My Missouri tax dollars at work! I'd go check it out, but the install is a 3 hour drive from me.

You need to do it just for the sake of getting photographic evidence of the ridiculous utility trench they have to build under the road.
If you live close, taking a few pictures each week as the work progresses would be very interesting. It could really show the massive scale of the work.
 

Offline Fungus

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #463 on: July 15, 2016, 07:50:11 am »
This makes solar roadways obsolete - 1 megawatt per square meter!

Quote
The potential of the new system is huge. According to their calculations, a 1m² membrane with 30% of its surface covered by nanopores should be able to produce 1MW of electricity

http://phys.org/news/2016-07-electricity-salt-three-atoms-thick-membrane.html

 

Offline mux

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #464 on: July 16, 2016, 09:32:53 am »
I've seen phys.org publishing some really shit quality articles lately. What is up with them. I thought they were an outgrowth of the scientific journals?
 

Offline SeanB

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #465 on: July 16, 2016, 10:49:00 am »
I've seen phys.org publishing some really shit quality articles lately. What is up with them. I thought they were an outgrowth of the scientific journals?

You pay the publishing fee and submit the paper. The check clears and it goes in the next available space in the edition..........
 

Offline Fungus

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #466 on: July 16, 2016, 03:48:01 pm »
I've seen phys.org publishing some really shit quality articles lately. What is up with them. I thought they were an outgrowth of the scientific journals?

I just saw it in Nature magazine as well. I thought they were more reputable.  :palm:

http://www.nature.com/nature/journal/vaop/ncurrent/full/nature18593.html

 

Offline 2PiRad

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #467 on: August 28, 2016, 01:39:50 am »
My hometown Hannover (Germany) is becoming a new member in this exclusive bullshit club.  :palm:

Solar bike path:
200m x 2.5m (between Ramlingen and Ehlershausen)
Build by WattWays or Solmove
235,000 €

Power could be used to light a bus stop and a crossroad.  :clap:
But it should generate power for 20 households  :-DD

A second bike path is planned with roof mounted solar panels:
100m x 5m (at Krähenwinkel)
231,000 €

Presentation from Department of transportation (pdf / german): http://regions-sitzungsinfo.hannit.de/bi/___tmp/tmp/45081036218561353/218561353/01116807/07-Anlagen/05/TOP411Solar-Radwege_Praesentation_VKA.pdf


 

Offline jonovid

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #468 on: August 28, 2016, 03:37:04 pm »
value adding too up government spending as long as it works at say 2%, somebody's got a job maintaining it   :bullshit:, even white elephants need a good scrubbing to keep clean with a brush and water.  :-DD
Hobbyist with a basic knowledge of electronics
 

Offline Barny

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #469 on: August 29, 2016, 09:53:17 am »
My hometown Hannover (Germany) is becoming a new member in this exclusive bullshit club.  :palm:

Solar bike path:
200m x 2.5m (between Ramlingen and Ehlershausen)
Build by WattWays or Solmove
235,000 €

Power could be used to light a bus stop and a crossroad.  :clap:
But it should generate power for 20 households  :-DD

A second bike path is planned with roof mounted solar panels:
100m x 5m (at Krähenwinkel)
231,000 €

Presentation from Department of transportation (pdf / german): http://regions-sitzungsinfo.hannit.de/bi/___tmp/tmp/45081036218561353/218561353/01116807/07-Anlagen/05/TOP411Solar-Radwege_Praesentation_VKA.pdf

Send a link of Daves Videos to the political oposed fraction of the town - mayor and ask, why they suport this stupide bull-s*
 

Offline Fungus

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #470 on: August 29, 2016, 12:11:37 pm »
Send a link of Daves Videos to the political oposed fraction of the town - mayor and ask, why they suport this stupide bull-s*

What distinguishes Dave from the people selling the solar roadways in the eyes of the mayor?

They both talk in nerdy concepts that make his head spin but only one of them is saying the mayor might get richer as a result.
 

Offline Delta

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #471 on: August 29, 2016, 12:42:20 pm »
Send a link of Daves Videos to the political oposed fraction of the town - mayor and ask, why they suport this stupide bull-s*

What distinguishes Dave from the people selling the solar roadways in the eyes of the mayor?

They both talk in nerdy concepts that make his head spin but only one of them is saying the mayor might get richer as a result.

That's why Barny said send it to the opposition politicians in the local government.  Give them a stick with which to beat the mayor!
"Why are you spending taxpayers' money on a project that costs SIX TIMES more per unit of electricity generated?"  should be simple enough even for politicians to grab.
 

Offline Fungus

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #472 on: August 29, 2016, 01:02:40 pm »
Send a link of Daves Videos to the political oposed fraction of the town - mayor and ask, why they suport this stupide bull-s*

What distinguishes Dave from the people selling the solar roadways in the eyes of the mayor?

They both talk in nerdy concepts that make his head spin but only one of them is saying the mayor might get richer as a result.

That's why Barny said send it to the opposition politicians in the local government.

I know what he said, thanks.

How exactly would the opposition use Dave's video? The same problem applies.
 

Offline Delta

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Re: EEVblog #632 - Solar Roadways Are BULLSHIT!
« Reply #473 on: August 29, 2016, 01:46:22 pm »

I know what he said, thanks.

How exactly would the opposition use Dave's video? The same problem applies.

I'm not sure where you are, and maybe you are somewhere were politicians are a bit more civilised to each other and less argumentative (and to be fair, I have no idea what local politics is like in Germany), but here in the UK, opposition councillors will use anything they can to attempt to besmirch the council leader!

Dave's video nicely boils it down to basic, monetary figures.   I'm sure even your average local taxpayer (who will have no interest or knowledge of electrical engineering or solar power) would understand and be annoyed by "six times the cost of the best alternative - as would the local media.

It's worth a try...
 

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