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Science Technology

Solar Shingles 63

buzban writes "Wired is carrying a cool story about a solar panel technology with a form factor like roofing shingles. Sort of a beowulf cluster of small, (relatively) attractive solar panels, if you will..."
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Solar Shingles

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  • by Maxite ( 782150 ) on Friday October 22, 2004 @07:37PM (#10605070) Journal
    Now how to keep kids with ladders from walking on your roof scuffing up the solar shingles.. Or people who have low roofs (there's one near my house, actually it's right across the street) where you can walk from the ground right up onto the roof in the back).
  • More Olde News... (Score:4, Interesting)

    by HotNeedleOfInquiry ( 598897 ) on Friday October 22, 2004 @07:37PM (#10605079)
    A duplex just down the block had these installed 4 years ago. Every time I go by, I'm tempted to ask them if they still work.
  • Two Words (Score:3, Insightful)

    by zygote ( 134175 ) on Friday October 22, 2004 @08:14PM (#10605391)
    Hail Storm.
    This sounds like a great idea. I'd be all over it except that at least once a year some part of the metro area where I live gets pounded with hail.
    I didn't see anything in the article about how these tiles would be manufactured to survive this or heavy wet snow.
    • Yeah, solar panels are so new and special that roofing manufacturers would never test them for really rare stuff like hail, wind, rain, sleet and snow.
    • I think they are sealed...

    • Re:Two Words (Score:5, Informative)

      by gCGBD ( 532991 ) on Friday October 22, 2004 @09:48PM (#10605997) Homepage
      Unisolar panels are made in Michigan.
      They have been out for several years.
      They withstand Hail.

      They're actually flexible and look like regular tar roofing tiles except instead of being coated with little "pebbles" they are smooth and black.

      They also offer a solution for standing seam roofs which are basically big rolls of "tape" that you stick down between the seams.

      Keep in mind that these things (amorphous silcon panels) have lower power densities than tradtional glass and crystal silicon panels.

      They are also a lot more work to wire up.

      The technology keeps improving however.

      They offer significant ascetic advantages which are important to a lot of people.

      They can also be mass produced in much larger batches than the other technology. (And therefore will eventually be much cheaper. That is if the increasing demand for them ever levels off...)

  • by Doc Ruby ( 173196 ) on Friday October 22, 2004 @08:33PM (#10605542) Homepage Journal
    How about paving roads with solar panels, under some hard (metamaterial) transparent aluminum? About 16M hectares of America is paved road and parking, so 20W:m^2 (of the 1KW:m^2 peak insolation) would give 32GW. That's 3.2E13W, when US power consumption is 1E13.
    • That's the stupidest idea I've ever heard. However, it has been estimated that the conversion of about 175 square kilometers in a high-sun area like the SW desert could supply electricity to the whole country. The problem is cost: it costs MUCH less to burn coal and generate electricity via traditional means. It costs about $5-8 a watt for solar - at efficiencies of about 20-30%. And that is expensive.BR>
      • Counting only the cost of the fuel is stupid. How much does it cost when the coal exhaust comes back as a string of hurricanes? Or an asthma epidemic? It's also stupid to think that we must choose one or the other alternate energy strategies. Wouldn't it be great for America to be a net exporter of energy to the world again?
        • Yes, it is stupid, but perception is more important than any of that. Besides, producing a solar cell of one watt releases about 400 kilograms of CO2 in the air. There are problems with every source of energy there exists: there is no cure-all that is free from all pollution. Solar energy is one option, but until it is necessarry - that is, until traditional means of electricity generation are discontinued - solar power will be reserved for those who live far from power lines or those who want to "live" the
          • Sugarcane gets 8% photosynthetic efficiency - the highest of any land plant (12% is the quantum mechanic theoretical maximum). Floating it downriver consumes little energy, and the total efficiency in a place like Louisiana from 1KW insolation thru the cane, fermentation, and a bioreactor fuelcell to electrons down a wire, means about 27W:m^2. Along the way, the chaff sequesters carbon for a net sink. If we don't get these alternates up and running now, while we have the luxury of choice, the momentum of ou
          • Where the *bleep* did you get that '800 kilo's of CO2' figure from? I do not beleive it. If you're going to make a statement of that extreme scale, you damn well need to cite the source.
    • How about paving roads with solar panels, under some hard (metamaterial) transparent aluminum

      How about waiting until we discover transparent aluminum before asking about building things with. You might as well as about using unobtanium or trilithium to build a new power plant.

        • The article you linked to is about alumina not aluminum. Their is a fairly large difference, aluminum is a metal while alumina is a ceramic. Like other ceramics, alumina is fairly brittle and will undergo failure without warning under high tensions or impacts.

          • Right - thanks for setting me straight. Metamaterials research is just getting started after their initial products, so I expect transparent materials hard enough to coat solar cells for pavement will be along eventually. By then we might have other solutions for collecting solar power from this unused public resource.
    • It wouldn't matter what it was made of, but any effort to get at some of the huge amount of energy falling upon roads around the world is a great idea.
      Roading takes a huge amount of space, is only utilised a small percentage of the time and is daily bombarded with a large amount of solar energy. If it was a cheap, clean technology, it would be far better for developing countries to use solar rather than expensive non-renewable technology.
    • by cr0sh ( 43134 )
      Living in Phoenix, Arizona - this is something I have thought about. I call it a DTEC (D is for desert) - basically, it is a land-based OTEC (I suppose you could also call it an "LTEC" - L for LAND, or TTEC - T for TERRA). The thermal gradient coming from either above ground collectors and below ground (where there is a constant temperature) collectors. The above ground collectors could either be actual solar collectors, or buried tubing in asphalt parking lots, etc.

      I am sure this isn't done, though because

      • If it isn't done, it's just because no one is doing it. If you can do it, try it - and get rich making it happen. When the water runs out in Phoenix, if there's still an energy industry there, the city might survive. Someone's got to be the one to do it.
    • How about paving roads with solar panels, under some hard (metamaterial) transparent aluminum? About 16M hectares of America is paved road and parking..

      While you are right that there is an inordinately large amount of paved area, I think another poster has enlightened you on the transparent aluminum problem.

      Still, along those same lines: just covering all parking lots with these panels would be a big step forward. Additionally, parking structures could have these *both* over the top level *and* down t

  • nope (Score:5, Interesting)

    by my_fake_account ( 823601 ) on Friday October 22, 2004 @09:19PM (#10605844)
    "Pernick said solar roofs would probably be adopted most quickly in states such as Hawaii and California where the cost differential between electricity derived from solar and fossil fuels is not as great."

    I lived in Hawaii for almost four years. Very few people use solar. Even for hot water. Instead they use electricity that is supplied by diesil burning plants.

    I talked to native Hawaiians about solar and mostly got blank stares-- even from one guy in HVAC. The only people out there using solar are hippies or those who just happened to move into an apartment or house with solar.

    Most people don't think about solar. Just like most people don't think about coal/NG/nuclear/hydro turbines. If solar is going to happen, it's going to take a concerted effort by... somebody. I'd assume it would be in the government's best interest, but apparently it's more important to fight for oil.
    • "apparently it's more important to fight for oil"

      Of course it is, people don't think about the other things (like you said).
    • Hawaii and California where the cost differential between electricity derived from solar and fossil fuels is not as great.

      Yeah but... Those are the two states that have the smallest delta between outside temperature and a desirable indoor temperature. Which any idiot should know results in the least amount of energy used and the longest payback (in that respect) for solar.
      • Re:nope (Score:2, Interesting)

        except for hot water. I agree-- there is really no need to have any air conditioning or heating in Hawaii-- the trade winds take care of the heat, and it is rarely cold (57 degrees F.-- brrr!) But hot water is a huge energy expenditure, and has nothing to do with photovoltaics, and is easier and cheaper that PV, but still, people don't even consider it.
        • I'm not sure how huge it is.

          I take a 5 minute, barely warm shower each day, rarely use hot water to wash my hands, and use cold water detergent in the washer.

          Now if I'd get off my butt and install a demand water heater so the whole tank doesn't have to be heated all the time, I'd say I was doing pretty well without solar.

          Factor in a couple of females and your milage will vary
          • "I'm not sure how huge it is."

            But HECO is [heco.com]-- they say conventional electric water heaters are the highest domestic electricity use.

            IIRC, as I was moving back to the mainland, they were offering substantial incentives to people on Maui to use solar water heating because they didn't want to have to build another power plant.

      • I'm betting you haven't spent much time in California. It's a big state, and includes a wide range of climates.

    • Why is do people always insist that the government take charge of every fscking facet of their lives?
  • 'Y'know why it's called "hail"?

    Because when you start hearing that "tick. TICK! thunk. THUNK! THUNKTHUNKTHUNK!" you say "OH, HAIL! There goes the roof!"

    That's one thing I did not see in the article - how does this stuff fare when you start getting one inch hailstones pelting it.

    Then add the 70+ mile an hour winds trying to peel it off.

    And if you live in California (excuse me, Kah-lee-FOR-nia), you have the ozone trying to "make friends" with the molecules of the roof. Again, how long will this last?
    • by jaredmauch ( 633928 ) <jared@puck.nether.net> on Friday October 22, 2004 @09:56PM (#10606024) Homepage
      Perhaps a quick inspection of related websites (easily found in google) "virtually unbreakable, and durable even in heavy hail conditions" [smartroofsolar.com]

      If I were out to build a new home, I would certainly consider this as a source of power. Even if you are not storing the power in a large battery bank, using what you generate to suplement your existing grid power would cause a decrease in your overall electric costs. Now, there's that whole capex vs opex discussion (cost of shingles vs potential monthly savings + maint costs) which would come into play.. I've mentioned solar and wind powered systems in the past.. if you dig, you can probally find my previous comments on the topic..

      • Also, don't forget about homeowners insurance. Not sure how it would handle solar powered shingles, but regular shingles are usually (at least partly) covered when a hailstorm takes them out.
      • Solar still has a ways to go. Solar is still not terrible energy efficent. You always need to include the energy it takes to build a solar cell before you declare it energy efficent. Generally, price is a pretty good indication as to how much energy has to be dumped into these things before you have something you can throw on your roof. Right now, the simple fact of the matter is that they are still far too expensive. I would love to lower my eletric bills with bonus points for the environment, but if
    • Yeah, umm ... break your bubble, man. Not every single inch on the planet is susceptible to hail. There are some places where hail would be welcomed; you can still nevertheless use these tiles to improve life conditions in those area's.

      Sometimes, it amazes me, how some peoples' arguments even get through their miles-thick bubble ..
  • More examples (Score:4, Informative)

    by the_twisted_pair ( 741815 ) on Friday October 22, 2004 @09:49PM (#10606000)
    This sort of thing has to be the way forward. A lot of work has been put into the field in the last 15-20 years, and now economies of scale are steadily bringing the costs down to reasonable. Five years ago, costs for PV panels were around the $10-12 per installed watt; today it's more like $7. We're getting there.

    Best of all, it's a fit-once solution that will last as long as any other material might be reasonable expected to, off-setting energy demand all the while. Oh, and the colour is a rather fetching blue-violet depending on where you view it from :)

    Here's a few more examples:

    Research on photovoltaics in cladding systems done here in the UK at Southampton Uni. [soton.ac.uk]

    The German cladding manufacturer Schüco [schueco.de] has a variety of well-developed photovoltaic cladding systems:

    More European examples [solarserver.de]

    A 60KW solar roof cladding installation in Berkeley, California [powerlight.com].


  • Every now and then I see homes where the owner has looped or coiled dark green garden hose onto the roof. Does anyone know what that's all about? Obviously, it must be a solar energy collection effort, but how does it work?

    Maybe the heated water flows down into some piping tie-in to the house's water supply or something.
    • How much of the roof does that cover?

      Around here, I've seen some overhangs with copper wire looped around on them. During the winter, electricity is run through them to heat them up and help prevent ice dams.


      • What I've seen is essentially a garden hose thrown up on the roof, I never thought to check to what it was connected (given my domain name, this might be considered gross negligence). Maybe it's just for hard-to-get-to storage though.

        Come to think of it, you have a point there. It could be used to melt ice on the roof. I'll get back to you, since this is the sort of thing that interests me. Yup, that's pretty pathetic, isn't it.
        • Cheap heated swimming pool water.

          Case of beer + garden hose on the roof + a mega-sized kiddies paddling pool = Delightful afternoon.

          And a good reason why the water is warm!
    • It could be this idea:

      WhiteCap(TM) Roof Spray Cooling System [pnl.gov]
      Cooling Technology for Warm, Dry Climates

      I have heard you can do it yourself as well.

    • The idea is that the water in the hose heats up, but a hose offers quite a high resistance to flow so you typically need a pump to keep it circulating. You store the heated water in a tank from where you loop it through the hose again, and it'll get warmer and warmer.

      A better solution you'll find in practically any house in Cyprus: they typically buffer drinking water on top of the house (for levelling pressure and demand), and you'll see a secondary tank fed below that which also includes a loop into a s
  • Solar cells typically take more energy to manufacture than they produce over the lifetime of the cell so from an efficiency standpoint they are a waste of energy.

    From another standpoint, however, they act as a kind of battery. You put a bunch of energy in to make the cell and you get much of it back as the cell converts sunlight to electricity.

    So, when would you need one of these batteries? How about when you live 30 miles from the "X" in the middle of Florida where three hurricanes crossed?

    Living withou
  • I only just figured out about MY monolithic dome plans, zoning, and, land acquisition! Oh well, I could build a SHED to roof! Only need about $40 worth of power per month, anyway! http://safeharbordome.com

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