Here in broken California, we can’t hardly get Cal-Trans to complete regular asphalt roadways on time or on budget. While this is a nice idea, and in a perfect world it might be a perfect solution, I don’t think it will be adopted quickly by cash-strapped state governments. OTOH, maybe Federal subsidies from carbon taxes imposed by the EPA?
The design features embedded LED lights for markers. But, it’s a trouble magnet for some kids to hack the system like has been done with construction signs. This passage from the article really told me though that he doesn’t have a clue:
Brusaw says that the solar road would cost about $4.4M per mile, but those costs are offset by not needing to build coal plants, install utility poles, and build relay stations. “The taxpayers are already paying for all of these.
Umm, there’s coal power plants being built in the USA at taxpayer expense?
Solar-Powered Glass Road Could Melt Snow Automatically
By John Brandon, Fox News
It’s being called snowmageddon – and for good reason. Snow and ice are wreaking havoc all across the United States with record wind chills and more precipitation than Siberia on a bad day. If your commute is taking three times as long as it usually does, go ahead and blame the archaic highway system.
That’s right. In the 1950s, the idea of paving America with black asphalt seemed like a good idea. Now, 60 years later, we’re still using it — and still sliding all over the road.
But what if the road itself could change?
That’s the dream for Scott Brusaw, who has a novel idea for dealing with snowy roads: replace them with a glass surface embedded with solar cells that generate power from the sun and store it in batteries for use at night. In his view, such a proliferation of solar cells could also help solve our ongoing dependence on fossil fuels, because they could feed excess electric power into the grid. He has even developed illuminated lane markings that change according to current road conditions.
His company, Solar Roadways is waiting for approval on a new $750,000 grant from the Federal Highway Administration (FHWA) that will help him build a large-scale prototype to test new materials and electronics, and hopefully prove that his invention works.
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
Let’s see, no math in the article, so let’s do some:
1 inch of fluffy snow on one sq meter of road weighs about 2kg, so let’s melt that inch.
1 sq meter of solar panels creates about 110 watts of power at noon in summer in northern CA when clean. And PVWATTS tells us the actual generation per day for a flat solar panel in Dec-Jan is 720 W-hr total per month or 23 w-hr/day. Let’s assume that the road is clean, as all roads are, especially in winter when it’s snowing.
It takes 333 kJ to melt 1 kg of snow. And that 1 sq meter of snow 1 inch deep would weigh about 2 kg… requiring 666 kJ to melt.
But the solar road only makes 23 w-hr, or 83 kJ per sq meter per day in winter.
So it would take the solar ice melting road almost a month to melt 1 inch of snow.
What a BRILLIANT idea, let’s borrow money from the Chinese for it!
The grandkids can pay it back.
Feet2theFire says:
February 6, 2011 at 6:28 pm
The government might have done something in the ’90s and early ’00s to stop the handover of our jobs, …. And we are all competing with $3.00/day labor in China and $3.00.hour programmers in India. … It will be a generation or two before we get manufacturing back – if ever.
You’ll never get wages back though. There’s no AGWanker value in just relocating industry. The whole purpose of deindustrialising the West is to bring about the permanent extinction of the “living wage.” (And nobody will be happier than Malcolm Fraser when that day comes.)
This is the very definition of a pipe dream. The construction of these roads would only increase the cost of solar panels because solar panels use rare earth minerals. Where have you heard rare earth minerals in the news lately?
George E. Smith says:
February 7, 2011 at 1:26 pm
The standard weight limit for semis is 80,000 lbs, 12,000 on the steering axle, 34,000 on the two drive axles and two trailer axles. If you slip into any of the various weigh stations operated by state DOTs on any given day you’ll usually find at least a couple units parked because either through intention or incompetence they were overloaded, sometimes quite seriously. One seriously overloaded semi can inflict major damage to either asphalt or concrete paving because it pushes the paving past its yield point. These dopes seem to draw encouragement from the fact that their are glasses out their that will stop a bullet, but if anyone actually shoots a bullet at it, it will need to be replaced. Stopping a bullet is a piece of cake compared to standing up to continuous truck traffic. Glass can be an amazingly strong material, but these folks evidently never heard of the concept of stress risers. You can cut glass with anything hard enough to make a small scratch in its surface. This thing is so incredibly incompetent that I fully expected to see a line at the bottom that said it came from The Onion News Network.
“”””” Dave Wendt says:
February 7, 2011 at 11:33 pm
George E. Smith says:
February 7, 2011 at 1:26 pm
The standard weight limit for semis is 80,000 lbs, 12,000 on the steering axle, 34,000 on the two drive axles and two trailer axles. “””””
Dave, I can’t comment on your numbers because I have no sources for such data. My comments were ( from memory) simply a description of the “H-20” Truck. No such truck exists. It is a defined hypothetical vehicle; the purpose of which is to use as a load on road and bridge structures, when designing such structures.
Your “semi” rig, would be 23 tons just for the truck (tow vehicle) which has the same configuration as the H-20; one steering axle, and two driving axles with dual wheels. Of coruse a semi tow vehicle wouldn’t have any 17 tons on the drive wheels unless it was towing a trailer, that provided most of that load.
So the H-20 is not a semi like vehicle but an ordinary “lorry”.
OOoops ! I lied; an H-20 truck has a single drive axcle with a 32,000 lb limit (16 tons) and an 8000 lb (4 ton) steering axle limit, for a 20 ton total.
Note that it has 16 tons on a single drive axle, whereas your semi rig has 17 tons for two drive axles.
But as I said , the H-20 is a hypothetical structural loading tool, not a real truck, and I believe it is NOT street legal, because of that 16 ton drive axle.
http://www.precast.org/precast-magazines/2010/07/hl93-truck-loads-vs-hs20-truck-loads/
And that AASHTO is the set of Standards that I had referred to. I only have the one volume; that deals with bridges and the like; they whole set of standards is way beyond my pay scale.
So if you are designing your own Golden Gate Bridge, instead of having to figure out what the loads and pressures would be with bumper to bumper commute traffic, or whatever; you simply distribute a bunch of H-20 trucks in some described fashion. It sound like the system has gotten considerably more complicated, with the various semi configurations, and of course as they mentioned, the Military loads.
Hey there is no limit to the ‘stuff’ you can learn at WUWT; stuff that would just go down the boring hole at c-r.
Do those guys actually imagine that they are performing a public service. Joe Romm and Gavin Schmitt should be totally ashamed of themselves, peddling that abomination as a scientific discussion site.
I have no idea who Tamino, or Eli Rabbett actually are either in their Puppet guise, or in reality; apparently they do have rather publicly known names. Well I still have no idea who they are; but they evidently have a pretty good idea what their stuff is actually worth; they even put some other name on it.
Well nobody knows who I am either; and I can even use my real name; but then you can find me standing on a street corner in almost any town anywhere; and I know that I am registered at 85% of all the Motels in the country; maybe only for an hour though.
I don’t always get my stuff right; or even correct; but as soon as I find out about it, then I change my story; which still may not be correct, but perhaps closer than my first attempt; and I’m not ashamed to put my name to it.
” Standard Specification for Highway Bridges” , is the document that I have; a big three inch thick 8 1/2 x 11 thee ring binder.
Note what that short link up above says, about how you use those things. You do not use the 16 tons on the rear axle, to be four 4 ton point loads, on whatever structural surface you are designing; you spread that total over the whole lane width, and the length of the truck; I’ll have to research the document to get the true details on that.
If each rear tire carried 4 tons or 8,000 # (short tons in British parlance), and the tire pressure was 125 PSI, that says you would need 64 square inches of tire-road contact to carry the weight. I measured some of those dually tires once, and the tread is about 8 inches wide, so the contact patch on the orad would be 8 inches long too. Now because of the rigidity of the tire rubber, the actual contact pressure is somewhat higher, so the contact is actually smaller than that. Then the 125 PSI spec on the tires, is the cold tire pressure, so it likely is 150 PSI or higher at max operating Temperature, which further lowers the road contact.
But somebody eventually has do do a finite element analysis, of whatever the structural surface is to be sure it is not going to get destroyed at the max operating pressure. And then you have to figure some sort of safety margin. For example, whereas standard structural steel is stated to have a 60,000 PSI strength; one would normally use something like 16,000 PSI as a design maximum, so nearly a 4:1 safety margin. And things can go egg shaped in a hurry, when you get into structures that could buckle.
These solar roads, are going to be something to behold; then again they are almost certain to be holed !
George E. Smith says:
February 8, 2011 at 9:11 am
I wasn’t attempting to challenge your post or the numbers you used, merely to point out one of the many daunting factors these clucks seemed to have dismissed with a magical handwave. I only used your post because your reference to axle weights relates to what I find to be the main difficulty with all these “magic highway” schemes i.e. what happens when you start to run a couple thousand semis over them everyday?
I was in the highway biz, actually public sector, for many years a long time ago and have found that most people,including engineers who haven’t dealt with it personally and more than a few that have, are totally unaware of the incredible engineering difficulties involved in building a highway that will stand up to modern traffic conditions and the wide variety of weather it will be exposed to.
what a pathetic thought.
The idea clearly has merit. It will die a sorry death, however, if it is rushed into implementation without adequate testing of prototypes under a wide array of conditions and abuses, cost/benefit analysis and MANY, MANY failures followed by improved design. I see practical roadways coming of this in a decade; perhaps two decades in cold climates.
“”””” Dave Wendt says:
February 8, 2011 at 10:40 am
George E. Smith says:
February 8, 2011 at 9:11 am
I wasn’t attempting to challenge your post or the numbers you used, merely to point out one of the many daunting factors these clucks seemed to have dismissed with a magical handwave. “””””
Dave, I was in no way critical of your post. I realized you were presenting actual figures for what real semis are allowed to do; and I realized that I hadn’t made it clear to the uninformed, that the H-20 Truck was a hypothetical artifact used in road and bridge designs, and not any real truck. So i was simply amplifying your input for those who as you point out see roads as not that big a deal.
I agree with you; the design of roadways that survive the abuse they get, is no trivial undertaking; which makes this Chritmas tree light highway, even more silly.
Hey, if you can power your house from a car’s fuel cell when that car’s hydrogen tank was filled using grid electricity in the first place, why not melt snow off a road that is getting so little sun energy that snow managed to stick in the first place?
(In the unlikely case that he won’t be able to fool the gov’t into giving him money, this guy should sell his plans at Instructables, where “the alternator is spinning anyway” is a good enough reason why running your car on hydrogen generated using only the car’s electricity should work.)