Dumbest idea I've even heard in my life

[JaredJames]

In theory yeah, but I can tell you, my driveway is about 10 degrees inclined, i spread normal salt (stupidly not rock salt) over it to get the ice off in winter, the water did drain, but it hit -10 at night and the thin layer of ice that formed was enough to put me flat on my arse when I stepped onto it! :D

We've got drainage on our driveway. Didn't do nothing though. Just got clogged and froze over.

It got so cold that the groundwater underneath froze solid. I know this because our 6 inch thick concrete drive (about 5m³ of concrete) rose 3 inches and cracked in half.

 

[Kawakaze]

@Mech yeah you're right there, but the point I making is that even a thin film of water is enough to be dangerous. I know I sure felt it!

@Jared Scary! Fascinating how something as innocuous as water can bring down rock faces and destroy concrete structures.

 

[NeoDevin]

It's yet another thing that makes this proposal ridiculous compared to snow plows, or even putting a roof over the entire road!

How much energy is required to plow the snow?

 

[Jasongreat]

Whatever it is, it wouldn't differ much if they plowed an inch of snow or a foot. Can the same be said of a heated road?

 

[JaredJames]

Is the cost of replacing the roads / installing required infrastructure (energy storage etc) along with maintaining said technology more or less than plowing it?

 

[Kawakaze]

I think I have a compromise. Most places where this technology would be useful are remote and sparsely populated. I propose we use the money to buy every household a half-track with fitted plough, or use it to forcefully evict them. If they want to live in a frozen hell, with 2 people per square kilometer they can pay to defrost their own damn roads! I don't see why I should subsidise someone who wants to live in a snowglobe. :)

 

[NeoDevin]

Whatever it is, it wouldn't differ much if they plowed an inch of snow or a foot. Can the same be said of a heated road?

Nope, but without a number to compare it to, that statement isn't much use.

 

[Jasongreat]

Nope, but without a number to compare it to, that statement isn't much use.

The plow would use around 880 joules(1/4 gallon of diesel fuel) of energy to plow a 8+ft wide swath one mile long. The driver would expend around 2 calories worth of energy at the same time, so just over 880 joules.

 

[mugaliens]

You are assuming that snow falls at an average rate of 1 inch per hour, and/or that no energy can be stored during times of less snowfall.

Asphalt roads are always storing solar energy, whenever there is solar energy to store. They're the last to freeze, and the first to thaw.

 

[NeoDevin]

Asphalt roads are always storing solar energy, whenever there is solar energy to store. They're the last to freeze, and the first to thaw.

They don't store it very well, or for very long.

 

[Curl]

people who think this is a good idea don't know what solar cells are, and have no clue how money works, and are also clueless about materials science.

in other words, ignorant on all levels

 

[gmax137]

I have thought for awhile that I'd like to get ahold of a couple of spent fuel rods from my local electric provider, grind 'em up and mix the grind into asphalt, and use that to pave my driveway. I'm paying the guy down the road $40 bucks everytime he plows the drive, what do you think my payback time would be? Do you think they would *give* me the rods, to, you know, take them off their hands?

 

[Max™]

I always wondered why we couldn't build solar cell awnings along/over most of the interstate system, at current efficiencies, assuming no significant improvements in the tech, we could provide the power needed for the US with a similar scale construction project to the interstate system.

 

[stevenb]

I always wondered why we couldn't build solar cell awnings along/over most of the interstate system, at current efficiencies, assuming no significant improvements in the tech, we could provide the power needed for the US with a similar scale construction project to the interstate system.

Sure, just place these on the sides of the road along with a few tables to relax at.

 

[pallidin]

I always wondered why we couldn't build solar cell awnings along/over most of the interstate system, at current efficiencies, assuming no significant improvements in the tech, we could provide the power needed for the US with a similar scale construction project to the interstate system.

And no-one would steal them?

 

[pallidin]

Furthermore, to meet even basic D.O.T. standards, the awnings would have to be at least as sturdy as an over-highway pedestrian crossing.
The cost per mile under those safety conditions would be enormous.

 

[Jasongreat]

Furthermore, to meet even basic D.O.T. standards, the awnings would have to be at least as sturdy as an over-highway pedestrian crossing.
The cost per mile under those safety conditions would be enormous.

And furthermore, the added costs of an expansion of the roadway would be enormous as well.

 

[mugaliens]

And no-one would steal them?

Oh, no - because everyone in the whole world is nice, polite, kind, and would never stoop to something as low as "stealing."

Yeah. http://en.wikipedia.org/wiki/Bill_the_Cat" !

 

[Amy G. Dala]

For what it's worth, he does say that the road will act as a network. I suppose he's thinking something lofty like maybe one part of the road might be snow covered but another portion may not. I guess he thinks he can transfer the energy or something. I don't know where he gets that idea because when it snows, all roads everywhere in the word are instantly covered by the exact same amount of snow at once.

Meh, stupid idea from an ignorant man with a POS prototype--someone should tell him to get back in his box.




https://www.youtube.com/watch?v=Ep4L18zOEYI

 

[JaredJames]

For what it's worth, he does say that the road will act as a network. I suppose he's thinking something lofty like maybe one part of the road might be snow covered but another portion may not. I guess he thinks he can transfer the energy or something. I don't know where he gets that idea because when it snows, all roads everywhere in the word are instantly covered by the exact same amount of snow at once.

Meh, stupid idea from an ignorant man with a POS prototype--someone should tell him to get back in his box.

I assume he's checked the amount of energy produced 'elsewhere' and how much of it can be transferred to the required areas (considering loses etc)? It usually snows over quite a large area and the nearest sunny location capable of producing the required energy levels is a fair bit away. Which means you need as many roads with this tech as possible, otherwise having it only locally is useless - unless you start drawing from the grid that is, meaning you need to recover that usage once the sun is back out.

 

[mheslep]

... Even if the industry can crank out solar polymers faster than humans crank out feces, it wouldn't be enough to do jack.

Well it will do jack and then some. Cover the tiny little squares in this graphic of the world with solar arrays and the energy produced w/ today's technology solar cells while the sun is shining is equivalent to the world's entire primary energy consumption, all of it - nuclear to coal to oil - day and night.
http://www.ez2c.de/ml/solar_land_area/
The trick yet to be mastered is in making and installing them economically and storing the energy, and having a transportation system that makes use of electric power somewhere in the loop.

 

[mheslep]

ROFL, this idea is so retarded is sad.

2) Laying solar cells underneath? Really? That is just completely stupid...

Did you read the article? Cells are one option, solar thermal heating the other:

"Think about it, we have more than 3 million miles of highways exposed to sunlight, so if we can harness this energy, it's free, and you don't need photovoltaic solar cells," said Mallick

 

[Borek]

880 joules(1/4 gallon of diesel fuel)

when it snows, all roads everywhere in the word are instantly covered by the exact same amount of snow at once

[URL]http://www.bpp.com.pl/IMG/faint.gif[/URL]

 

[thopsy]

There are two reasons why this idea is "dumb": 1) ineffective hybridization, and 2) ineffective utilization.

1) People are often too quick to think that combining things offers some sort of savings. Why would you combine a solar panel with the road pavement material. This offers no savings. Roads are made of grippy and durable asphalt. Panels are made from delicate semiconductors...If you really want to use solar for this, why don't you just place the panels beside the road? Cheaper road, cheaper panels. Even still it would be a bad idea because:

2) Ineffective utilization: Convert solar electricity into HEAT to melt snow?! Anyone who knows anything about the second law would roll over in their grave at mention of this!

Oddly enough, asphalt is a fairly good solar absorber, and insulator on its own, try walking barefoot on a road on a sunny day.

 

[thopsy]

Sorry, if there was mention of solar thermal in the article, I may have overlooked it. I didn't read beyond mention of " super-strong glass, instead of conventional asphalt or concrete". But use of a thermal absorber and storage medium to increase the average pavement temperature is, I think, a good idea. Any use of photovoltaics in this application is ridiculous, and that comes from a PV engineer.

 

[thopsy]

This also reminds me of a CNN article I read about a car the runs on water...hehehehe...water.

 

[Jasongreat]

[PLAIN]http://www.bpp.com.pl/IMG/faint.gif[/QUOTE]

Sorry Borek, didnt mean to make you faint and hit your head. I don't have any idea how I came up with that number, I have tried repeatedly to come up with it again and I have not been even close to being successful.

Here goes my next try, a ten wheeler gets about 4-7mpg, taking the lower end, one quarter of a gallon will cover one mile, the energy density of diesel is 45.3 MJ/kg, one gallon of diesel weighs 3.402 kg so one quart would weigh .8505 kg, which would leave us at 38.53 MJ/mile(one pass around 9 foot wide). Is this close or have you just fainted again?

Assuming this try at math was successful, it would take 4 passes to completely clean a one mile section of 2 lane highway from shoulder to shoulder with the plow, which would make it 154.12 MJ of energy expended. According to Mech Engineer (post #51), to get the same area to melt one inch of snow it would take 2.3MW/h. 2.3 MW/h converts to 8280 MJ, so it would take 53.72 times more energy to melt the snow. If it takes pretty much the same energy to plow 1 foot as it does to plow 1 inch, the difference in energy expenditures between plowing and heating would be even more enormous(since it already is for an inch), and that's before we even discuss the added costs of building the heated roads, maintaining them and storage facilities for the energy they make.

As you probably already know, I'm no mathmatician nor a physicist or even a college graduate, so please correct me where it is needed. I am here to learn but fainting emoticons don't teach me much other than that I was wrong. If this thread is not the place to further this discussion, could you please PM me an explanation of where I went wrong. Thanks.

 

[Borek]

the energy density of diesel is 45.3 MJ/kg

Without checking details - this is a correct ballpark figure. And you got it on your own, so me fainting was a correct approach.