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Solar Roadways Get DoT Funding

mikee805 writes "Solar Roadways, a project to replace over 25,000 square miles of road in the US with solar panels you can drive on, just received $100,000 in funding from the Department of Transportation for the first 12ft-by-12ft prototype panel. Each panel consists of three layers: a base layer with data and power cables running through it, an electronics layer with an array of LEDs, solar collectors and capacitors, and finally the glass road surface. With data and power cables, the solar roadway has the potential to replace some of our aging infrastructure. With only 15% efficiency, 25,000 square miles of solar roadways could produce three times what the US uses annually in energy. The building costs are estimated to be competitive with traditional roads, and the solar roads would heat themselves in the winter to keep snow from accumulating."

14 of 484 comments (clear)

  1. Oh, get real. by russotto · · Score: 5, Insightful

    Solid concrete and asphalt get ripped apart in short order by the combination of weather and heavy vehicle traffic, and they propose to use solar panels to drive on? I'd say it's a bold engineering project, but it's gone beyond "bold", past "insane", past "so crazy it might work", and right into "let's see if we can get dumb ideas paid for if we call 'em green".

    1. Re:Oh, get real. by Brian+Gordon · · Score: 5, Insightful

      just put some super tough clear material over the top of the cells and you've dealt with the wear and tear

      Another laugh out loud moment. This thread delivers.

      I imagine you going to the materials engineer on retainer for your states DoT. "I noticed we're spending $30 million a year resurfacing roads. Send a little of that my way and we can solve that problem. My idea is to put a super tough material over the top and we'll have dealt with the wear and tear."

    2. Re:Oh, get real. by Jedi1USA · · Score: 5, Interesting

      One other problem with concrete is that at the "seams" (not to mention the cracks) between panels water can get through to the ground underneath. This can lead to localized soil expansion/contraction which causes stress on the concrete and accelerates the deterioration. If a lot of water gets through the ground can be unstable enough to allow the panels to "rock" then they don't line up evenly any more. I would think these large glass panels could be susceptible to the same problem.

      --
      My old sig was REALLY stoopid.
    3. Re:Oh, get real. by brusk · · Score: 5, Insightful

      What about the middle of the night, when there's much less traffic?

      --
      .sig withheld by request
    4. Re:Oh, get real. by Anonymous Coward · · Score: 5, Insightful

      Ironically, common, ordinary glass is a VERY VERY durable roadway surface which admits light. Anything thicker than 6 inches, and supported by compacted earth underneath, would EASILY handle the weight of a vehicle driving over it. The problem that glass has is that it has a very low reflexive modulus, meaning that it doesnt take tortion or bending stress very well at all. (It shatters.) This makes it a poor choice as a structural material for buildings, other than as the outer shell, where it's strong resistance to weathering suppliments the high reflexive moduluous of steel girders.

      For a roadway, it would work very well. The problem would be people with sledge hammers being knob-gobblers, and damaging roadways-- and other bone headed "Lets drop a super heavy object on the roadway and see what happens" kinds of faux-pas. (Dropping the great big industrial dumpster on the glass roadway would be a no-no.)

      I suggest glass over say-- recycled polycarbonate plastic (Recycled water bottles) because the former does not decay on exposure to UV light, does not leak Bisphenol-A into the ground water, is not flammable, and doesnt produce toxically accumulating microparticles from surface abrasion that gets washed out into the ocean.

      Now-- That said-- there WOULD be problems with a glass roadway.

      1) It tends to be rather slick when it leaves the factory, especially if you want it to admit light well. (Solutions might be to dimple the surface, or to make it "rough" with rounded bumps on the surface, which would actually allow it to admit and trap more light internally-- however, then it would harbor dirt, roadkill residue, snow, snow control sand/gravel/salt, and any other "able to be ground into a surface" materials, which would inhibit the solar pannel functionality.

      2) The energy costs in creating that much glass. This might not be such a problem though-- there are similar energy expenditures in the creation of concrete. (Both require kiln operation.)

      3) "Sharp particles" being produced by people being retards, and doing things to the road that one realy shouldnt do. (Like do a high speed chase on flat tires, and subsequently driving on rims, or dragging a turned over trailer down the road because you got drunk when you were at the lake-- etc.)

      4) Some other consequence I havent thought of yet.

      But, for the record-- the main reason we use asphalt as a roadway surface is because it makes a convenient place to deposit oil refinery waste. (Asphalt is a refinery biproduct from crude oil-- essentially crude oil solids.) Other nice things about are is that it doesnt rot, it self-repairs to a limited extent, can be poured/pressed into place, and makes a nice gripping surface.

      If we stop using fossil fuels as an energy source, we wont have a ready supply of asphault to resurface roadways with either-- so researching alternative roadway surfacing materials is a must if we are to move away from this doomed energy source.

    5. Re:Oh, get real. by Rei · · Score: 5, Insightful

      Yeah, I don't see that happening.

      And why not? Sun = 1000W/m^2, decreased by angles, obstructions, night, etc. Let's say 8kWh/day/m^2 on a clear stretch of road. That's 6.88Mcal/day/m^2. Latent heat for melting ice is 80 cal/g and temperature raising is 1cal/g/C, so 10C temperature rise and melting is 76.4kg snow per day at 100% efficiency. Snow is about 100kg/m^3, so that's .764m^3 per m^2 per day, or 2 1/2 feet per day.

      Now, obviously, efficiency isn't 100%. Solar cell efficiency is about 15% in this application. However, the "waste heat" isn't exactly waste; it's heating up the road. Now, it radiates away instead of being stored, but what's there is useful. Anyone who lives in a northern clime can tell you how the first snow after a warm period tends not to stick well. And even the 15% solar efficiency -- call it 12% after grid and storage losses -- times 2 1/2 feet is 4 inches of snow per day, or 27 feet of snow per winter.

      What, you think nobody bothered to check the numbers before issuing the grant?

      --
      Dear Lord: I don't want to go back to college, so please help me be sexy. Amen.
    6. Re:Oh, get real. by Rei · · Score: 5, Informative

      Is reading the FAQ too much to ask?

      Try this: Go to Google Maps and start looking at roads. Random roads. Select without bias. Tell me how much of the road surface is covered on average. Then go deliberately seek out traffic, and again, tell me how much of the road surface is covered.

      Even in "bumper to bumper" stop-and-go traffic, about half the roadway is exposed. On average, a quick glance at the US's road system suggests that perhaps 98% of it is exposed at any point in time during the day, and perhaps 90% in cities.

      --
      Dear Lord: I don't want to go back to college, so please help me be sexy. Amen.
  2. Unsafe? by digitalmonkey2k1 · · Score: 5, Interesting

    I'm sure they did fairly decent testing with 4 wheel vehicles, but my motorcycle lacks the inherent stability that a car has. How bad would a surface like this be when it gets wet?

    --
    My sausage tree didn't grow, does that make me a bad mommy?
  3. The claims in summary = article + meshed/shortened by virmaior · · Score: 5, Informative

    at least one of the claims here seems a little off: http://www.solarroadways.com/The%20Numbers.htm

    in particular, this sentence: "This means that if each individual panel can be made for no more than $6912.00, then the Solar Roadwayâ can be built for the same cost as current asphalt roads." It seems to assume that an outlay of 3x the money for a road that lasts 3x as long is the same cost as 1x & 1x respectively. While this is true for someone with infinite readily available money, the reality is that most places don't have enough money for that.

    also "The Solar Roadwayâ will, therefore, eliminate half of the greenhouse gases currently being produced. " seems to be a dramatic overstatement.

  4. Duh... by AlexBirch · · Score: 5, Funny

    They are going to cut 1/2 the greenhouse gases by getting more and more cars off the streets and into repair shops!

  5. Re:yeah right by negRo_slim · · Score: 5, Insightful

    Also why do they have to make roads out of them.. where did that come from? Just put them out on land somewhere, you don't have to drive all over them.

    Yes let's go tear up what's left of arable land and natural habitat for our never ending thirst for energy. People will point to the desert as if it's some vast lifeless tract of land. Which is simply not the case.

    --
    On the Oregon Cost born and raised, On the beach is where I spent most of my days
  6. Re:A dumb argument by jtorkbob · · Score: 5, Insightful

    There is this thing, though, called snake oil. Politicians love it, these days even more so when it's 'Green Snake Oil'.

    --
    AC: Only on slashdot... could the sentence "My hovercraft is full of eels." be moderated "+4, Insightful
  7. The smart money is on solar roofs by Animats · · Score: 5, Interesting

    A much more effective concept is solar roofs. Rather than putting panels on top of roofs, the panels are the roof. This has many advantages. Rather than paying for a roof and solar panels, plus the headaches of attaching panels to a roof, you only pay for one surface. Mounting roof panels to rafters is easier than mounting panels to existing roofs. The wiring is on the inside, where it's in a dry space. The panels behave better in high winds, since winds can't get under them. And you can mix solar panels and plain roof panels, using solar panels only on the surfaces pitched to get the most sun.

    Roads are a much tougher environment than roofs.

  8. Re:A dumb argument by copponex · · Score: 5, Insightful

    Who bought up mass transit systems across the united states and shut them down? Who has been lobbying for the prohibition of natural drugs, and profiting immensely off of the sales of their own derivatives? Who shut down their production electric vehicle line and sold the patents to an oil company once there was no state requirement to produce a zero emissions vehicle? No one's talking about imaginary carburetors except for you. I'm talking about the self-evident fact that unpoliced corporations will destroy anyone and everything in order to turn a profit, even if it means dooming their country to reliance on foreign resources or destroying local manufacturing by moving jobs overseas. Especially now that corporations are international, they will exploit anyone who allows them in, and if you think for a moment that Exxon or Microsoft or Bechtel care if there is a just and equitable society anywhere, you're just not paying attention.

    The reason the market works sometimes is because there's competition. But there can't be competition without regulation. That's why the rest of the western world pays half of what we do for health care, transportation, and communications. That's also why they still have a middle class and less poverty, even in Germany, which absorbed it's communist half not even 30 years ago. In these countries, the rights and values of the society are more important than the private profits of corporations. This is due to active democratic action and unions, who are vilified by corporate culture for a very simple reason: they are the only check to corporate power, because they have the ability to influence the government and represent the will of people. (Not that they succeed in this goal all the time, or are innocent of corruption.)

    I'm sure you're enamored with your quips, and at least the effort matches the quality, but you're failing to provide any interesting points. So provide me with the narrative. Show me where a corporation engaged in pure research, brought a product to market without government subsidy, and revolutionized the world. For bonus points, show me where they decided that the product was so beneficial they'd allow anyone to produce it for the betterment of mankind.