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New Technology Turns Windows Into Solar Panels

Posted by CmdrTaco on from the i'm-sure-that'll-work-fine dept.

An anonymous reader writes "A start-up in Northern California is working on creating 'solar windows' that could act as solar panels at the same time as blocking sunlight from entering office buildings to reduce their energy needs."

61 of 86 comments (clear)

  1. Office buildings? by Anonymous Coward · · Score: 1

    Why restrict this to office buildings? I wanna live in a solar panel too!

    1. Re:Office buildings? by theIsovist · · Score: 2

      Why restrict this to office buildings?

      Surface area. Most (if not all) homes lack the sq.ft. of glazing required to make a transparent PV array viable.

    2. Re:Office buildings? by Anonymous Coward · · Score: 2, Interesting

      It will eventually be a common technique when building homes. At some point in the future you will have solar shingles, solar windows, in wall solar panels with light redirected from above to make use of the dead space and possibly even solar paint (depending on house style) that all feed into the same generation system. Unfortunately it isn't viable today and all of those technologies have to be developed to be separately viable before they can be combined into some sort of piecemeal home unit that generated/collected enough energy to make a difference. The place you start with the glass materias would obviously be the giant glass buildings all around us, AKA office buildings.

    3. Re:Office buildings? by Anonymous Coward · · Score: 1

      Hey, Mr. Snark. The post you are replying to talked about the area "of glazing", not the total surface area. Outside of some expensive, modern architectural homes, most are not covered in window glass. They are covered in opaque walls with a smattering of small windows. However, many more office buildings are covered in glass.

    4. Re:Office buildings? by Geotopia · · Score: 1

      "New Technology Turns Windows Into Solar Panels"

      I knew someone would figure a good use for Windows. Hopefully there won't be driver and registry problems with the Solar Panels.

  2. Light in on the subject by Anonymous Coward · · Score: 1

    Isn't the purpose of a window to let light in, not absorb it?

    1. Re:Light in on the subject by royallthefourth · · Score: 3, Insightful

      This would be useful for a window that has the sun shining directly into it during the morning or afternoon; you only need so much light coming in!

    2. Re:Light in on the subject by TWX · · Score: 2

      We like having nice views here in Arizona, but large windows are very bad for the temperature of the structure. If one could reclaim some of the cost of the air conditioning with solar power then it's more practical to have large picture windows.

      I for one would like to see this integrated into automobile glass, with it powering a combination battery-monitoring and air circulation system. It could be used to reduce the interior temperature of a car by cycling out the hot air with less-hot air from outside while the car sits out in the sun all day. It would make it less bad when getting in and would possibly prolong the life of the interior components. One could even make a combination solar panel and LCD crystal windows, such that the operator can park, turn on the fan, and then whiteout the windows so that even less light makes it inside.

      --
      Do not look into laser with remaining eye.
    3. Re:Light in on the subject by ledow · · Score: 2

      Yes, and solar is already incredibly worthless without having to steal only "some" of the light, while letting the rest through, and being transparent (or at least semi-transparent), and not being 4-inch-thick, and providing access to the conductor to carry the electricity away, in a glass panel tested to all the relevant standards, on a couple of hundred square meters on the side of a building in a city (which won't be in direct sunlight for quite a lot of the time, unless it's the tallest building around for quite a long distance because of shadows!), with technology that's been suggested and abandoned a dozen times before but never successfully implemented, not to mention the COST of installing all that solar (presumably at design, because retro-fitting will be a bit of a nightmare) for exactly how much gain? A handful of kilowatt-hours every day (which you could save just by cutting out a couple of windows and replacing with a better insulator) assuming even the most efficient panels in use today. It will cost more to run the lifts to move that glass into place and in copper to wire them up than it will ever generate in its usable lifetime... same old solar story as always.

    4. Re:Light in on the subject by theIsovist · · Score: 4, Insightful

      That's one purpose of a window. Thanks to modern building techniques, we have the option to create much larger openings in the facade, and thus you get your typical glass and steel skyscraper. Ever notice that they all have a reflective, metallic tint to them? This is to keep much of the light out, because in a large office building, your interior temperature suffers heavily from the amount of light let in. You also have an issue with glare, which tinting can help with as well. If your solar system reduces the amount of solar gain and the amount of light into the building while still allowing some light/vision/heat in, you can forgo the window tinting, and make the windows even more useful.

    5. Re:Light in on the subject by NervousWreck · · Score: 1

      Windows with southern exposure get light all day. Sometimes it gets a bit much, especially in hot areas in the summer. The windows are tinted anyway, why not get some use out of them?

      --
      I do not have a sig. You are hallucinating.
    6. Re:Light in on the subject by gstoddart · · Score: 1

      One could even make a combination solar panel and LCD crystal windows, such that the operator can park, turn on the fan, and then whiteout the windows so that even less light makes it inside.

      And, just think of the benefit to teenagers and other people who want to go 'parking' ... no more finding a dark secluded place. Just pull over somewhere, and blank out the windows for a bit and have a quickie.

      Of course, the vigorous rocking of the car might be a give-away, but, it's a small price to pay. :-P

      --
      Lost at C:>. Found at C.
    7. Re:Light in on the subject by EvilStein · · Score: 3, Insightful

      I'd be happy if we had a solar charger that worked well enough to charge my iPhone. :/ Tried a couple different brands and they were all awful.

      One day...

      and it's my opinion that the biggest barrier to solar panel adoption in the United States right now are homeowner associations. My worthless HOA forbids solar panels. (Sadly, it is legal for them to do so under state law.. for now, Texas is trying to strip HOAs of that power)

    8. Re:Light in on the subject by GameboyRMH · · Score: 2

      Yep imagine that your house's roof let some light in, just enough that you'd never have to turn lights on until sunset, even in the innermost rooms. You could have 90% of the light turned into electricity and the rest used to light your home during the day.

      And no you wouldn't need to worry about aerial spying, your roof would look like what car guys call "slut-black tint."

      --
      "When information is power, privacy is freedom" - Jah-Wren Ryel
    9. Re:Light in on the subject by uncanny · · Score: 1

      Isn't the purpose of a window to let light in, not absorb it?

      Then what are blinds/curtains for?

    10. Re:Light in on the subject by Dayze!Confused · · Score: 1

      It might be interesting if a cloud floats over the car :-D

      --
      "All tyranny needs to gain a foothold is for people of good conscience to remain silent." [Thomas Jefferson]
    11. Re:Light in on the subject by jbengt · · Score: 1

      Glass windows have at least three purposes:
      Keep out the heat, cold, wind, rain, and snow.
      Let in light.
      Allow a view of the outside
      Most windows are designed specifically to keep the heat of the sun out and reduce ultraviolet light transmission, which also happens to cut down on the amount of light let in. The typical design attempts reduce heat gain and fading as much as possible while letting in as much visible light as desired, but it usually comes down to a trade off that easily computes in favor of reducing both visible light and heat. (In most climates. In the colder, less sunny climates, it can pay to let in the heat and light.)

    12. Re:Light in on the subject by Mister+Whirly · · Score: 1

      Just a guess here, but to possibly block the sunlight/heat from entering? Or even to block someone outside from seeing inside?

      Did you really just actually ask what curtains are used for???

      --
      "But this one goes to 11!"
    13. Re:Light in on the subject by skids · · Score: 1

      Some light. Not all wavelengths and not all light, though. The rest is intentionally absorbed or reflected.

      --
      Someone had to do it.
    14. Re:Light in on the subject by GameboyRMH · · Score: 1

      Of course, the vigorous rocking of the car might be a give-away, but, it's a small price to pay. :-P

      Nothing active suspension can't take care of. Crank up the shocks to maximum stiffness (using a servo-controlled valving knob or magnetic fluid suspension) and you'll hardly be able to rock it.

      --
      "When information is power, privacy is freedom" - Jah-Wren Ryel
    15. Re:Light in on the subject by Em+Adespoton · · Score: 1

      OK... your HOA forbids solar panels. Do they specify panels? Because solar arrays come in many forms, panels only being one of them. It's possible that solar window arrays or solar roofing arrays or solar sheets would not run afoul of your HOA, even though people might grouse about some of the options enough to re-word the bylaws.

    16. Re:Light in on the subject by makapuf · · Score: 1

      You're not doing it right.

    17. Re:Light in on the subject by uncanny · · Score: 1

      That was in response to the person thinking that blocking light coming in through windows was a new or otherwise weird idea. Try reading the whole thing for once.

  3. 'New Technology Turns Windows Into Solar Panels' by jabberwock · · Score: 4, Funny

    Linux has been doing that for years. Microsoft rips off open source, yet again ...

  4. "new" as in "sold since several years"? by rbrausse · · Score: 1

    A company called Konarka developed fully transparent cells in 2009, brownish and blueish cells from Sunways are already used in existing buildings.

    1. Re:"new" as in "sold since several years"? by krotkruton · · Score: 1

      And the Sears / Willis Tower in Chicago is slated to have such windows installed: Chicago Tower Solar Farm

    2. Re:"new" as in "sold since several years"? by Stellian · · Score: 1

      Another green fad. PV are only marginally cost effective when they tracking the sun. A PV cell that is engineered to look nice and has 3 hours/day angled sunlight will probably break even when hell freezes over.

    3. Re:"new" as in "sold since several years"? by rbrausse · · Score: 1

      I couldn't believe your claim but it seems you're right...

      I found informations about the PV installation at the main train station in Freiburg - it was build (mostly for political/design reasons) with vertical solar cells (see page 38 for a picture).

      according to the details on page 41 (upper table in the right column, German only...) the annual output is 59 kWh/m2, this paper estimates the energy requirement for monocrystalline cell modules (including frame, supports, inverter and human labour) to 7900 MJ/m2.

      Amortization time 37 years, or 120-150% of the expected lifetime.

    4. Re:"new" as in "sold since several years"? by kyle5t · · Score: 1

      Since I install solar for a living I was curious, and I looked into this system a little bit. There are a number of problems here:

      * multicrystalline silicon requires more energy to manufacture, out of proportion to the increase in production efficiency
      * Germany, despite having very generous incentives, is actually about as bad in terms of solar resource potential as Alaska
      * the modules used should be more efficient than 10%, even considering the semi-translucent design
      * the balance of system components could be a lot more efficient than 86%: this is an area that has improved considerably in recent years
      * the expected losses due to shading (15%) seem a little high considering the height of the building
      * yes, you do take a significant hit installing in a vertical orientation

      Add it all up and it makes for a system that should never have gone in. But these types of building integrated designs are worthwhile when done properly.

      Typically, the Energy Return on Investment is around 3 or 4 years and it should be no more than about 10 years for an installation like this one.

    5. Re:"new" as in "sold since several years"? by kyle5t · · Score: 1

      meant to say monocrystalline silicon, actually

  5. Learn something everyday by vawwyakr · · Score: 2

    Here I thought windows that "block sunlight" were called walls.

    1. Re:Learn something everyday by MikeBabcock · · Score: 1

      And you've never heard of sunglasses either?

      --
      - Michael T. Babcock (Yes, I blog)
    2. Re:Learn something everyday by RivenAleem · · Score: 1

      Any company would rather make their offices floor to ceiling in glass, but then they get too much light in (the office being too bright is not the problem, just overheating), and thus have to install blinds. This ability to siphon off some of the heat will work in their favour.

  6. About time by mbone · · Score: 3, Insightful

    I've only been hearing about this for, what, about 30 years. I imagine cost is the crucial factor, as otherwise some of those other startups would be ubiquitous now.

    Even in this case, the article says "CEO Fink wouldn't reveal his system's cost per watt ," so I bet cost is still a factor.

    1. Re:About time by DaveGod · · Score: 1

      The system's cost per watt straight-up isn't necessarily useful. What's interesting is the relevant cost per watt of this system, that is the cost over and above that of the regular tinted windows you would otherwise be buying.

      Furthermore with "cost per watt" I'm never really clear whether or how much they are counting for the land required. Again there is nil relevant cost with these windows.

    2. Re:About time by jklovanc · · Score: 1

      Cost per watt is an easily manipulated number. I most cases I bet it is based on optimal production and measured at the panel. I doubt very much it takes into account any of the following;
      Cost and power loss of equipment to convert from DC to AC
      Maintenance cost of panels and conversion equipment.
      Decreased output due to window facing, time of day, time of year and atmospheric conditions.

  7. This has been done years ago by Graywolf · · Score: 2

    A quick Google search turns up results from at least as far back as 2007 and one article (apparently offline) from 2004.

    I guess the new product will be more efficient, but this is definitely nothing new.

  8. Windows 7 by CPTreese · · Score: 1

    It really can do anything!!!!!!

    --
    If there is no God then free will is an illusion.
  9. Re:Aw damn... by MikeBabcock · · Score: 1

    Meh, I prefer set-top boxes that let me watch my Netflix via my TV and surround-sound system without paying the PC premium. YMMV.

    --
    - Michael T. Babcock (Yes, I blog)
  10. Well.. by cyberchondriac · · Score: 1

    I guess we'll have to wait and see if this tech is viable. Every year it seems some new solar tech comes out with big promises, and quietly dies in whispers.
    I haven't given up hope though; long ago I had given up on LED tech as any sort of serious display tech or light source, and suddenly(?), there were: LEDs that make gorgeous displays of all sizes, LEDs that for all colors of the visible spectrum and then some, and LEDs that put out 110 lumens (who'd a thunk?). I just hope there's a similar breakthrough sometime soon in solar cell development, but this probably ain't it.

    --

    Look back up at my post, now look back down, you're on the Internet. Now look back up. I'm a signature.
    1. Re:Well.. by rahvin112 · · Score: 2

      They aren't dieing. See that's the problem when you have a 2 second attention span. Most of these inventions are being incorporated into viable production lines. From discovery to production is at least 5 years and that's if they already have a factory in place that can utilize the new technology. If they have to build the factory as well it's another 2-3 years. So when you hear about one of these great new ideas do you check back on it in 8 years? Didn't think so.

      Bulk solar power is on our door step, otherwise GE wouldn't have just bought one of the most important thin-film solar producers, coincidentally the company in question was already building the largest solar cell production plant in the world. The CdTe panels that this company produces use little of the very expensive rare earths that the other panels do, they can be produced on roll-roll processes (flexible panels as well) and it's expected that they can be produced for significantly less than a $1 a watt (considered the break point for mass acceptance).

    2. Re:Well.. by rahvin112 · · Score: 1

      I use GE in the analogy because GE requires that every division they own produce 20% returns or the company is sold. They have a corporate policy to avoid risky ventures and their movement into any new industry is a signal that industry has achieved a certain level of acceptance and growth that fits the GE prospects. As the single largest industrial conglomerate in the US they are a sign of a real market being developed. Up until the First solar acquisition GE only lended their name to solar panels (buying from current producers and branding as a sell in product on other industrial lines). With the purchase they are probably going to be the largest thin film producer in the world with more capacity in the single factory under construction than nearly every other factory in the world combined.

      But if you don't buy the GE angle, here is the other one. Solar panels are considered cost competitive against other power sources (nuke/coal/wind/gas/etc) when prices hit $1/Watt. At that price you can achieve $2/Watt installed and with a 25 year guaranteed life your amortized costs per watt bring a commercially viable power rate against traditional base load generation. The beauty of solar is that it also tends to peak output on a very similar curve to the usage peaking curve. Anyway, if you bother to read this the following is informative: (http://www.solardaily.com/reports/Historic_One_Dollar_Per_Watt_Solar_Modules_Just_Months_Away_999.html) as according to the article the per/watt prices of panels at the 2011 solar expo in Munich hit $1.35 a watt by the end of the fair and are predicted to hit $1 by the first quarter of 2012.

      Please understand that if Solar becomes cost competitive against coal generation we'll hit a major inflection point where solar power could become a significant portion of power generation.

    3. Re:Well.. by cyberchondriac · · Score: 1

      Well, if things pan out for them, that would be awesome- I wish solar tech would take off, I really do; I still have some reservations about any cutting edge tech and the promises and claims that developers or mfgs make regarding it, but obviously from time to time the claims pan out. Please understand that I've been reading about solar in Popular Mechanics since the 70s', they usually made it sound like a revolution was right around the corner, and to date, it's not quite where they suggested it'd be. Solar is due. But why couldn't you have just originally made your point without resorting to the insults and ad-hominem attacks as you did in your first reply? I wasn't trashing solar tech nor claiming to be an expert. Our last two exchanges were so much more productive.

      --

      Look back up at my post, now look back down, you're on the Internet. Now look back up. I'm a signature.
  11. Re:Like Most Multi-function machines... by erroneus · · Score: 1

    At first I was thinking "oh! I want one!!" Now I am thinking "damn, this thing will end up converting all the light into heat losing any benefit I might have gotten."

  12. Depends on cost. . . by JSBiff · · Score: 1

    If the solar windows cost a buck more than regular windows (not saying they do have that little cost difference, just rhetorically speaking), then even if they didn't provide much power, it might make sense to buy them instead of 'regular' glass, no?

    It all comes down to costs, not efficiency. Better efficiency would be great, but even marginally efficient PVs could be useful so long as they are cheap enough.

  13. RTFA for fuck's sake by EvilStein · · Score: 3, Informative

    From the article:

    "The company Pythagoras Solar is based in San Mateo, California, "

    It's the same company.

  14. Taxes can't make something "cost effective" by JSBiff · · Score: 1

    A technology either is, or isn't, cost effective. Using government subsidies might lower the cost to the end-user, but doesn't actually reduce the cost per kWh. It just makes the rest of us pay for someone else's over-priced power.

    The only argument I can see possibly being in favor of energy subsidies for solar or wind is the argument that it's essentially government spending on R&D to help get the technology and economies of scale advanced to the point where it can pay for itself.

    Unfortunately, people just see a lower price tag and dumbly say, "See! Solar power is cheaper than other sources!"

    1. Re:Taxes can't make something "cost effective" by Arlet · · Score: 2

      You can use taxes and subsidies as a way to incorporate hidden costs into a product. For instance, using a coal power plant to generate electricity may be cheap, but only by using current coal price, and ignoring some of the environmental/health damage it does. If you know prices are going to rise in the next 25 years, and you know that the solar panels have a similar lifespan, it's only fair to make some adjustments.

      Of course, hidden costs must also be incorporated for solar technology whenever they apply.

    2. Re:Taxes can't make something "cost effective" by JSBiff · · Score: 1

      Yes, that's true. I don't think I would personally have a problem with a tax on coal which was only used to pay for the hidden costs of burning coal - helping to offset health care costs (e.g. help pay part of the costs for people with Asthma, etc), property damage due to things like acid rain from coal emissions, etc.

      That seems only fair, really. It would also make other power sources more cost competitive, but I bet the republicans wouldn't allow it. If it did get through, the money would probably be spent on other things, anyhow.

  15. In most of the world... by Super+Dave+Osbourne · · Score: 2

    You can use passive heating and cooling in the design of a structure and do without HVAC for most of the year. Bottom line is architecture and society's whim is responsible for selling inefficient systems to the public, the public is guilty of being dumb/ignorant, and the oil industry sells the stupid people what they want for 2000% over their cost and get stinking filthy rich and powerful. Who's to blame? Nearly everyone!

  16. Into what? by Opyros · · Score: 1

    "New Technology Turns Windows Into Solaris"? I'm overdue for a new eyeglass prescription, it would seem.

    1. Re:Into what? by Capt.DrumkenBum · · Score: 1

      "New Technology Turns Windows Into Solaris"

      I don't know whether to be happy, shocked, frightened or appalled.

      --
      If I were God, wouldn't I protect my churches from acts of me?
  17. Been around for ages by Maury+Markowitz · · Score: 1

    You can buy off-the-shelf solar windows from several companies. We normally deal with Scheuten or Schott.

    1. Re:Been around for ages by Anonymous Coward · · Score: 1

      The question is, what do they cost?

      That is,

        X = normal window with coatings to limit solar illumination
        Y = windows with added PV

      cost = Y - X

      then how much that cost is per watt? If it is more than about $1-$2/watt, it obviously doesn't make sense.

  18. Re:sounds good to me by jbengt · · Score: 2

    I suppose you could use the windows to block out the light, and then use the solar energy to power the lights inside of the room. Win-win!

    You've obviously never designed air conditioning or lighting for a commercial office building with a lot of glass:
    Windows are often designed with overhangs above to block direct sunlight, adjustable blonds to allow occupants to reduce bright light and glare, and reflective and absorbent coatings to reduce the light and heat transmission.
    You can block most of the sunlight and still get more light from the window than from the electrical lighting (within 15 to 30 ft of the window).
    In most climates, the cost of air conditioning due to the sun shining on windows is greater than the cost of lighting and heating those spaces.

  19. Re:Like Most Multi-function machines... by jbengt · · Score: 1

    Can you imagine the wiring issues compared to wiring on the roof?

    Yes, I imagine it would be slightly cheaper to install indoors. On the roof doesn't require ladders or scaffolding, but does require weather-proof conduit, boxes, and devices and supports that protect the integrity of the roofing.

  20. Simple. by DarthVain · · Score: 1

    "...act as solar panels at the same time as blocking sunlight from entering..."

    So what you mean to say is take current technology solar panels and use them for windows? As that would accomplish the same goal.

  21. Wait, isn't lighting an energy need? by Zadaz · · Score: 1

    Back in the '80s they used to put tinted windows on buildings to block the sun to reduce air conditioning bills.

    Then they realized that when they did this they spent more on lighting since the sun couldn't get in. So they moved to coatings that reflect heat but let the light through. Air conditioning bills down, lighting bills down, everyone wins.

    Now they want to harvest the daylight, so that they can use that electricity to... light the office?

    *sigh* I'm all for harvesting waste energy, but these don't harvest waste energy, they harvest something we're actually using!

    Solar concrete. Now that would be something.

  22. Guardian Industries also working on this by kanwisch · · Score: 1

    A relative is an employee and showed me an article from an internal newzine talking about this kind of development too. They have deeper pockets, I bet, too. Anyway, I recall it showing an auto moonroof application that I presume is oriented at electric/hybrid vehicles. But the company has many large building contracts so that would be a presumed application as well. As has already been noted, the question is value.

  23. Solr windows has been out for several years by billrp · · Score: 1

    it's written java - what's the story here?

  24. Re:sounds good to me by YrWrstNtmr · · Score: 2

    adjustable blonds

    Go on..tell us more...