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Earth Power Hardware

Pumping Sunlight Into Homes 182

ByronScott sends a snippet from Inhabitat that begins "What if you could light your entire building using no electricity or artificial lights – but just the natural light from our favorite star, the Sun? Enter the Sundolier, a powerful sunlight transport system that's like putting a solar robot on your roof to pump sunlight indoors. The manufacturer claims a single Sundolier unit can provide enough light to illuminate a 1,000-2,500 sq. ft. area [93-232 sq. m] without any other sources." The company's website is a bit thin on details, such as what happens on cloudy days, or how many days of sunlight per year on average are needed for the device to perform acceptably.
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Pumping Sunlight Into Homes

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  • There are no details (Score:5, Informative)

    by BobPaul ( 710574 ) * on Monday April 05, 2010 @01:06AM (#31730694) Journal

    It's thin on the details because there are no details. This is just a flexible aluminum tube and a diffuser. The only thing different about this than the kits you can get at Menards is the big collector array which tracks the sun.

    There's no solar panels in this system. On cloudy days, you use electric lighting.

    Our Sundolier delivers sunlight so effectively that electric lighting can be turned off when the sun is out offering excellent opportunities to save electricity while reducing heat generation through cool indirect daylighting.

    There's no mention anywhere, not in the inhabitat.com article, nor the companies website, that this does anything on cloudy days.

    • It's a solar collector, plenty of them out there and better designs than this.
    • I recall reading a while back about a company that replaced some of their big fluorescent tubes with fiber-optic arrays that piped in sunlight, this seems like a fancier version of that.

      • by BobPaul ( 710574 ) * on Monday April 05, 2010 @01:56AM (#31730920) Journal

        Or a less fancy version. The article says

        The concentrated light is then reflected down a two foot tube and distributed using a “sun chandelier”.

        Fiberoptics would allow you to snake light to various rooms, into basements, etc. That seems more useful.

        • Re: (Score:3, Interesting)

          Considering it's for blunt transfer of light I think the fiber version might be cheaper too since you could basically make it out of the cheapest still-transmitting rejected cables.

          I'm not sure how much the cheapest functional cable for this is though, or how flexible, although the real trick would be getting the light into the fiber-optics to begin with. Some kind of half-pipe and tube-collector design both capable of just being hosed down by a home user is obviously the best solution but probably also exp

        • Fiberoptics would allow you to snake light to various rooms, into basements, etc. That seems more useful.

          I think it would require a very thick bundle to bring in enough to usefully light a room, so could be prohibitively expensive.

          As for lighting a basement with this, you would just need a place where you could reasonably have 2.5 by 2.5 foot - or 2.5 foot diameter - column (maybe smaller depending on construction, but the tube would need to be enclosed) going down through the intervening floor(s). Since basements are typically a single large room, doing this might be worth the cost of such a column - provided

    • Mixing CTB and CTO (Score:2, Informative)

      by Anonymous Coward

      I noticed that they are mixing color temperatures [wikipedia.org] in that video.

      Sunlight is CTB-- "color-temperature blue" -- about 6500 Kelvin.
      Tungsten lights are CTO - "color-temperature orange" -- about 3200 Kelvin

      When you have a big skylight but use tungsten lamps to light the same room, the effect is this weird blue/orange clashing effect where areas lit by the different light sources appear to have different hues. The same thing is common in grade schools or offices where blue light from the windows collides with

    • by dbIII ( 701233 )
      Australia's CSIRO was working on a light pipe that's similar to a big fibre optic cable a few years ago. I'm not sure what happened to that.
      • by MrKaos ( 858439 )
        I saw the same thing, looked like a great way of getting sunlight into parts of the home that it was difficult to.
    • by Lumpy ( 12016 )

      Also the same thing can be done with a single skylight in each room. Far more effective and gives you a beautiful view of the sky in every room. NOTE: dont put skylights directly above showers... A lot of people do this, ask hot air balloonists how many naked people they see through them.

      P.S. if you have opening skylights you can significantly reduce your cooling bills as well. If you try and tell me about the "energy savings of the tube ones versus the real skylight. I laugh. a leaky reflective tub

    • They have a set of powerful light on the concentrator. That way, the same tube can be used by all.lighting. Otherwise, if adding lights and these, it is too expensive. Though to be fair, I suspect that this really is too expensive.
    • by cptdondo ( 59460 )

      Google Ships Crystal, or its more modern equivalent, manufactured by solatube or velux (and probably a gazillion others.)

      Not sure what the news is here, other than they got a big, complex, mechanical thing on top that costs money and needs fixing.

    • In other words, this is a pitch to foolish investors who are looking to put money into green technology, much like many of the "this project will fix the environment" slashvertisements that pop up from time to time.

      The trouble is that most green technology is along the lines of cheap and simple, not expensive and patentable. For instance, this gizmo might even work, but is going to have far less effect on your greenhouse gas emissions than living near where you work or commuting by public transit. Similarly

  • by cnkurzke ( 920042 ) on Monday April 05, 2010 @01:09AM (#31730712)

    this works amazing, we should find a new name for this revolutionary device, how about we call it a WINDOW????

    only downside, it doesnt work when it's needed most, namely AT NIGHT, when it's dark.

    Maybe WINDOWS version 2.1 will fix that??

    • by Vinegar Joe ( 998110 ) on Monday April 05, 2010 @01:12AM (#31730728)

      only downside, it doesnt work when it's needed most, namely AT NIGHT, when it's dark.

      That's not a bug.....it's a feature.

      • by ebuck ( 585470 )
        For a few dollars more, they will sell you a built-in day / night indicator. If you act now, they will sell you the product at the fully price with the day / night indicator thrown in for free!
    • by martas ( 1439879 )
      i don't understand your negative reaction. i for one would love to be able to get natural sunlight in a room with no windows. and even if the room has windows, sometimes their placement means that the direction from which the light comes isn't convenient (think horrible shadow on book while studying with your back to a window). sometimes it's too bright. sometimes it's too hot, and you want to close the shades. sometimes you want to do the same for privacy. there are many potential reasons why this could be
      • by dgatwood ( 11270 ) on Monday April 05, 2010 @01:43AM (#31730864) Homepage Journal

        This has lots of interesting uses, but homes are not generally the primary market. Light pipes are most useful for businesses. You want to build a big office building to minimize cost, which means that not everybody can have a window office. So what do you do? You put in light pipes so that you can significantly reduce your energy costs and significantly improve worker health and morale.

        Same principal applies to apartment buildings, hotels, etc. Imagine a sun deck with outdoor-style gardens at ground level in a 20-story hotel. Imagine cutting the lighting bill for an entire office building (including interior rooms) to zero almost every day. And so on.

    • by gmuslera ( 3436 )
      You should not use organic materials to build those windows. It attract bugs,is perfect for growing up virus and other health threats, and are so easy to break that they dont protect you against thieves. Over that, you need to do permanently big expending on cleaning solutions.
    • Come on, we all know Slashdotters live in their parents basement where windows won't do any good. This could finally get some sunlight to them before they evolve into mole people.

  • by Hadlock ( 143607 ) on Monday April 05, 2010 @01:13AM (#31730732) Homepage Journal

    This has been done in the 3rd world for ages. You drill a hole in your roof, mount a 2L soda bottle filled with water (and two cap-fulls of bleach to keep it clean and clear), and stick an old black plastic film canister overtop of the white lid to keep the plastic from degrading. The video of these in use is amazing. Sadly however it only works when the sun is up - which is most of the workday (12 hrs typically) in the tropics.
     
    Watch it in action. Wow. http://www.youtube.com/watch?v=_zMAWztZ6TI [youtube.com]

    • This was worth the article. I have always felt if we just thought about things more, there are natural ways to have things even better than we have now. Lighting has been something that was on my mind lately. This is giving me ideas.

      • by am 2k ( 217885 )

        As natural as a 2L plastic bottle is anyways ;)

        • Who says you have to use a 2 liter bottle? Find a natural replacement and you have all-natural lighting! (Oops I said that out loud, now the marketers are going to catch wind and bastardize it!)

    • Hey man... thanks for that. I'm glad to see how much easier/cheaper you can do it for at home and may actually make use of that kind of design for a shop or garage or something.

      One thing I must say about the originally pointed out product and these bottle ones.... the light looks really appealing. It looks very natural and cozy, like when you have a well lit home that gets most its light from nice location and windows.

      Rockin!

    • by value_added ( 719364 ) on Monday April 05, 2010 @02:07AM (#31730978)

      Maybe you're the person to ask ...

      Some years back I stopped for a meal at a restaurant in the historical district of a small town here in California. The restaurant was a converted barn of some sort and had two large double doors for an entrance. During business hours, those doors were left open, as were another set of interior doors that led to an open air patio outside. Hanging on the wall by each sets of doors was a large 1-quart ziplock bag. The bag was filled with water.

      Noticing the bags, I asked the owner about them. She told me they were there to keep the flies from coming into the restaurant. I asked how a water-filled bag worked to keep flies away, and she said, "No idea, but do you see any flies in here?" Indeed, there were no flies to be seen (though there were some outside). She went on to tell me that that they had a regular fly problem years back, and one day a local immigrant gardner suggested the bags. The rest, as they say, is history.

      I'd guess an entomologist might be the one to ask, but have you heard of this technique being used?

    • by Inda ( 580031 )
      That's cool. I think my garden shed, which is too far away from the house to make running cables worth the effort, is going to get two holes in the roof today.
      • by pla ( 258480 )
        I think my garden shed, which is too far away from the house to make running cables worth the effort, is going to get two holes in the roof today.

        I thought something like that at first, too... Then fortunately pondered the implications before getting out the hole-saw.

        Why does your garden shed have a roof in the first place? Mine keeps out the elements, rain in particular. Rain, which has the most amazing ability to work its way into the smallest of cracks, trickle along studs, and drip into exactly t
    • That spreads the light a lot better than a simple hole in the roof and gets around the problem of the light coming from different angles.
    • That's great. It shows very nicely the difference between the western techno-fetishistic approach, that would produce big shiny solar panels at enormous expense to run the electric lights, and true human ingenuity.

    • That was cool. It's not an accident that this was invented in tropical Brazil. If insulation is a requirement for your roof (heating where required will dwarf light usage, especially with fluorescents), using sunlight for lighting will require different technology. But this is awesome for those areas, or non-insulated buildings in temperate or colder regions. It should be fairly frost resistant, having a relatively large thermal mass. In climates with snow it may explode unless you put a hole in the lid.
      • Re: (Score:3, Informative)

        by Lumpy ( 12016 )

        You can do the same with acrylic rods. We did that for a insulated ceiling building in northern Michigan. we had the top of the rod cut at an angle and had that angle set to the south east as lighting was more important to be bright in the morning. 3 foot long 4" diameter clear rod cost less than $40.00 each and the cutting and polishing was done on site with a saw and acetone. inside was crudely faceted to spread the light around, shaft was painted with white wall paint.. plus you dont get a heat

    • That's a really useful trick... Good for barns, garden sheds and places that are usually dark. Cheaper than a skylight and less maintenance as well, probably.

      As for the high-tech thing mentioned in the article... that would be a lot more useful if the "lights" had a lightbulb fixture inside of them, and a system to automatically add more artificial light if the sunlight dims for a moment (for example, if a cloud passes). That way you get a constant brightness inside while still saving energy.
    • 50W lightbulb using a common 2L Bottle

      This is basically functioning in the same way as a ship's Deck Prism [wikipedia.org]. These were big glass blocks that were used in ships as a way to guide and diffuse light below decks. Edmund Scientific sells them:
      http://scientificsonline.com/product.asp_Q_pn_E_3038621 [scientificsonline.com]

  • Bradbury story (Score:5, Interesting)

    by wisebabo ( 638845 ) on Monday April 05, 2010 @01:19AM (#31730758) Journal

    There was a story by Bradbury (sorry slow internet here don't want to look it up) where they had "picture" windows made of glass(?) with an extremely(!) high index of refraction. These windows had been left out in some scenic location (African savannah) and because the velocity of light was so slow through the glass, it would take years for the light to get through! Thus a "perfect" 3D display of whatever the window had been exposed to.

    Sounds (extremely) farfetched but in "light" (ha ha) of the discovery of a method to slow down or even stop light (admittedly in a Bose-Einstein condescent in a near perfect vacuum just above absolute zero), it is not entirely fantasy. Not entirely.

    • "Light of other days", is all I can find. I think that's Clarke, though.

      Anyway I remember it, I liked that story. A bit sad at the end, though, when the guy flips his glass over so he can look into his own house and see his late wife as she was 10 years ago.

    • by andrewbaldwin ( 442273 ) on Monday April 05, 2010 @02:05AM (#31730968)

      I think you mean "Other Days, Other Eyes" by Bob Shaw

      Thanks for reminding me -- I read it many years ago and enjoyed it - may re-read it now :-)

      It also appeals to another Slashdot meme - an evil government using crop-dusters to sow millions of shards of 'slow glass' to act as passive surveillance.

    • by Twinbee ( 767046 )

      So what is the longest we can currently slow down light for at room temperature?

  • What exactly makes this a robot?
    • Re: (Score:3, Informative)

      by BobPaul ( 710574 ) *

      The collector has servo motors so it can track the sun and maximize the amount of light sent to the diffuser. Otherwise it's just the same standard aluminum tubes you'd find in any solar collector installation.

    • by xs650 ( 741277 )
      My guess is that it tracks the sun.

      One big problem with a device like the one in the article is that by following the sun, the light level varies much more as cloud cover changes than light from a normal skylight does.

      I have some 10 inch diameter tubes with a clear raised plastic cap, a reflective lining and a diffuser in the ceiling. The provide as much light as a 100 Watt electric light and because they are aimed directly at the sun, the difference in light level doesn't vary as drastically with time of
  • Are you rich? (Score:2, Insightful)

    by mikeiver1 ( 1630021 )
    Don't know about you but I am not rich. Look at the fabrication work on that thing. For starters what do you do when the rain hits the reflectors. Water spots and wind blown dirt won't effect the performance of the reflector assembly in a detrimental way. I am sure that the proud owners will not mind in the least climbing up on the roof and cleaning the reflectors and admittance windows. Should be fun on a 12/12 pitch roof install. Dual tracking motors, those are really reliable and will never fail i
    • Re: (Score:3, Insightful)

      They are not going to give it away. Another rich mans folly.

      You'll notice two things about their site:
      1) No prices.
      2) No "home" applications listed.

      We're not their target market anyway.

  • Reflective tubes and fitting collectors are known for decades now! Nothing new about it. Remember that Dilbert house some years ago? Yeah, that one had them too.
    It’s useless beyond passing one roof and one floor. But if that fits, it’s really great for places where you can’t use windows. Especially if the windows are on the sides, while the roof is above you. But if the roof is right above you, of course a simple window makes more sense. ^^

  • by GNUALMAFUERTE ( 697061 ) <almafuerte AT gmail DOT com> on Monday April 05, 2010 @01:29AM (#31730810)

    Increase the speed of learning
    Directly impact student performance
    Improve student behavior
    Recruit the best teachers who seek the best environments
    Highest quality light = highest quality learning environment

    The Heschong Mahone Group analyzed test scores of over 21,000 students in multiple school districts. The study showed that students with the most daylighting in their classrooms progressed 20% faster on math tests and 26% faster on reading tests when compared to students in the least daylit classrooms. Heschong Mahone Group, "Daylighting in Schools" Report at www.h-w-g.com, 1999.
    In a North Carolina Performance Report, students attending daylit schools outperformed the students in non-daylit schools by 5%-14%. National Renewable Energy Laboratory Report, " Daylighting in Schools: Improving Student Performance and Health at a Price Schools can Afford, " 2000.
    A National Renewable Energy Laboratory Report concluded that students benefit from daylighting, both in terms of increased performance and general health and well being. National Renewable Energy Laboratory Report, "Daylighting in Schools: Improving Student Performance and Health at a Price Schools can Afford, " 2000.

    Wow ... "increase the speed of learning?". Given crackpotery on their site, the poor science, the ridiculous claims that instead of focusing on fucking light delivered, focus on subjective, unmeasurable bullshit, the complete lack of details, video, specs, etc. this product doesn't sound very serious ...

    • by Mashiki ( 184564 )

      They're just trying to make learning by osmosis a reality.

    • by thsths ( 31372 ) on Monday April 05, 2010 @01:57AM (#31730928)

      > Wow ... "increase the speed of learning?"

      Actually that is an important point. Most artificial light is so poor that it hinders whatever you try to do. It is well known how to produce better lighting, but it is just not done. When was the last time you experienced lighting that can adjust the color temperature, for example? That is quite an essential feature to keep your day rhythm working properly, and it has been shown to improve learning results significantly.

    • Re: (Score:2, Insightful)

      by drinkypoo ( 153816 )

      Wow ... "increase the speed of learning?". Given crackpotery on their site, the poor science, the ridiculous claims that instead of focusing on fucking light delivered, focus on subjective, unmeasurable bullshit, the complete lack of details, video, specs, etc. this product doesn't sound very serious ...

      If you compare to incandescent light, this is all probably bullshit. If you compare to fluorescent light, then I believe it. Fluorescent light has been shown to cause migraines in a significant percentage of the population, and it negatively affects attention span in nearly everyone. Nobody knows why yet; maybe it's the flicker, which suggests that the latest high-frequency stuff might not do it; maybe it's the lack of spectrum, with emission centered hard on certain peaks, forcing you to work harder to see

      • by ebuck ( 585470 )

        Raising fish has given me a lot of insight into light. Put an incandescent bulb above a fish tank and you'll do better than nothing, but will likely cook your fish (and the light isn't enough to do much anyway). Put a cheap fluorescent bulb above a fish tank and you'll get enough light (but in the wrong bandwidths). Put a good fluorescent light above a fish tank and you can sustain plant growth.

        It is obvious to other fields too, the best lamps used by quilters are ott (sp?) lamps. My mom swears by them.

  • I bet I could sell A LOT of these. I mean the average /.er wouldn't buy it, but most people don't think scientifically (or logically).
  • Old news, the Texas State capitol had to be extended almost 20 years ago. The extension is like 3 stories underground. On the top 2 or maybe all 3 stories they added some skylights and windows so that sunlight could go down into the rooms and natural light could be available. Even if you are underground, it never feels like it.
  • by Anonymous Coward on Monday April 05, 2010 @02:11AM (#31730992)

    Something like this one: http://www.sunlight-direct.com/ uses fiber optic cables to catch the sunlight and then send it around corners/to other floors/etc. It also doesn't work at night . . . yet. But throw in a few undersea cables (interlight backbone) and we could have a daylight exchange program with nations on the other side of the planet.

    • But throw in a few undersea cables (interlight backbone) and we could have a daylight exchange program with nations on the other side of the planet.

      wow this is not funny this is insightful!

  • by GlenRaphael ( 8539 ) on Monday April 05, 2010 @02:31AM (#31731044) Homepage

    When I had a house built back in 1998, "Solatube" lighting was one of the build options. From this pictures, this looks like the same thing with a slightly different input lens for a system like this:

    http://www.solatube.com/residential/product-catalog/brighten-up-series/index.php [solatube.com]

    I bought one to brighten a dark bathroom. It was nice. pretty much the same effect as a skylight, but it worked even where there was an attic in the way that would make a standard skylight unworkable.

    • Re: (Score:3, Informative)

      by Ubergrendle ( 531719 )
      That was my take...what is old is new again, but they've been selling these in canada for about 10 years (at least). Because the collector is raised off the roof and half spherical, it takes a substantial snowfall to cover the light collector...its maybe ineffective 1-2 months of the year.
    • by bkr1_2k ( 237627 )

      Exactly... light tubes like this have been around for quite a while. We haven't done it yet but we've been planning one for our master bathroom remodel for the last 5 years.

  • The company's website is a bit thin on details, such as what happens on cloudy days...

    Are consumers really that stupid that a company now has to explicitly state what their product does when it loses its power source?

  • by petes_PoV ( 912422 ) on Monday April 05, 2010 @03:44AM (#31731322)
    Though this one, looks far too complicated, with it's solar tracker 'n' all. Too much to go wrong for what has generally been considered a simple solution due to it's low-tech approach at getting light into a space.

    However they all suffer from the same drawbacks. You want lighting when it's dark - not (just) during the day, so you still have to install conventional lighting too. Plus they aren't so good when it's cloudy. They also pump in all the solar heat as well as the light so you use more energy than you save cooling the place down.

    • Re: (Score:3, Interesting)

      They also pump in all the solar heat as well as the light so you use more energy than you save cooling the place down.

      It is possible to design a collector to take advantage of chromatic aberration to limit the amount of light outside the visible range that gets in, therefore limiting the amount of heat.

  • Hey! (Score:4, Funny)

    by icebraining ( 1313345 ) on Monday April 05, 2010 @05:04AM (#31731650) Homepage

    our favorite star, the Sun?

    My favorite star is Proxima Centauri, you insensitive clod.

  • There have been a few mentions that something like this would not work on cloudy days.

    Without seeing further evidence to the contrary, I'd be more inclined to believe that it wouldn't work as well as it would on sunny days, but would still work better than conventional indoor lighting.

    As gray & dreary as it may be outdoors when the sun is hiding behind a cover of clouds, it's all really more of a mental illusion. Measure the light with a light meter (as a photographer would use) and you'll find it's sti

  • A little UV exposure is good for most of us, and a lot is bad for most of us. How much UV do these units transmit?

    • A little UV exposure is good for most of us, and a lot is bad for most of us. How much UV do these units transmit?

      Probably very little, unless they went the extra trouble to use lenses and mirrors that transmit UV as well as visible light.

  • I think you could look to Edgar Rice Boroughs for prior art. Does prior art have to be from the planet Earth?

  • This idea is not new at all... I used to work for a company that holds the original patents on this type of technology (http://www.solatube.com/), and has making these types of things since the 80s. Their product was far less obtrusive, and from the inside looked a recessed can-light, and not the transporter deck from the star ship Enterprise. Their overall luminosity was far greater too, and multiple warehouses and factory floors already use this tech. The technology around carrying light through a t
  • nukdolier (Score:4, Interesting)

    by MrKaos ( 858439 ) on Monday April 05, 2010 @08:10AM (#31732726) Journal

    This is a problem much more easily solved by placing miniature nuclear power plants on peoples homes to generate electricity for internal lighting. Obviously no one has considered the danger from indoor sunburn from these lamps and a rooftop nuke would be a much more reliable solution that a glorified and much more complicated, sun mirror.

    What happens when it's cloudy? Such a stupid idea to use the sun for light during the day as it is *obviously* not as reliable as a rooftop nuke.

  • It's slashdotted, but reading people's descriptions, it sounds like this thing is just the Japanese "sunflower" fiber optic sunlight pipe from 20 years ago. I remember seeing it on a "new technology" show back in the early 90's. IIRC, it was the same episode where I learned that Brits spell aluminum differently.
  • by HikingStick ( 878216 ) <z01riemer&hotmail,com> on Monday April 05, 2010 @08:40AM (#31733048)
    I remember reading about this technology in the late 1970s or early 1980s in Weekly Reader, a print publication for the lowest elementary school grades in the U.S., designed to get kids interested in reading about a broad range of topics. One issue featured a Japanese office building that had a solar collector (a parabolic dish) on the roof, and then fiber optic cables that were run to various offices. Because the fiber carried so much of the sun's intensity, they had to terminate the fiber runs behind a diffuser (similar to what photographers used). I've been itching to see the technology reach the consumer market for years and years--I'd love to have natural light cycles visible in our basement rooms, and at the office I'd love to minimize our use of light fixtures when we could use natural light.

    If you have kids in school who still get Weekly Reader, take some time to read it with them. I've been amazed how, time and again, their predictions and insights into new technologies have been right on the mark.
  • but... (Score:3, Funny)

    by flyingfsck ( 986395 ) on Monday April 05, 2010 @09:26AM (#31733554)

    does it run Linux?

    Sorry, someone had to ask.

    • Re: (Score:2, Funny)

      by jarbrewer ( 1254662 )

      does it run Linux?

      More importantly, could you set up a sufficiently large Beowulf cluster of these things to light, say, 1/2 the earth at any given time?

  • Cost (Score:3, Informative)

    by Anomalyst ( 742352 ) on Monday April 05, 2010 @09:27AM (#31733558)
    Per their company president: $15K + install
  • Yes, we know of windows and skylights (windows in roofs). Neither routs light througout a building.

    But light-pipes do. In smaller buildings (houses) they are hemispherical light gatherers with basicaly reflective conduit. In larger strructures, they are fiber-optic.

    Cool, but not new.

  • Except for the fancy shaped moving collector, it's similar to this:
    http://huvco.com/products.php?product=parans [huvco.com]

    Fat fiberoptic cable leads the light to a diffuser inside the building. The advantages are it's smaller than the tube on an ordinary skylight and can make sharper bends.

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