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Businesses Technology

'Smart Glass' is Coming To a Building Near You (axios.com) 93

Among the Inflation Reduction Act's little-noticed yet potentially game-changing provisions: a big incentive for "smart glass," which can make buildings significantly more energy efficient. From a report: Buildings account for 27% of annual global carbon dioxide emissions, by one estimate. While eco-friendly buildings aren't as sexy or exciting as electric cars, anything that makes them greener is a big win for hitting climate goals. The IRA, which President Biden signed into law earlier this month, includes a 30% smart glass tax credit. While it didn't get much mainstream attention, that credit stands to increase adoption by reducing the effective cost of retrofitting old buildings or using smart glass in new construction.

Smart glass, also called "dynamic glass" or "electrochromic glass," differs from regular glass in that its tint level can be adjusted on demand -- think Transitions glasses, but for buildings. Smart glass contains thin layers of metal oxide. When small amounts of electricity are applied to those layers, ions move between them, changing the glass' tint level. When the summer sun is hitting the side of a building, the tint level can be increased, allowing visible light to pass but blocking some solar radiation -- thereby reducing incoming heat. Conversely, the tint can be decreased in colder seasons, allowing more natural heat to pass through. Smart glass can help reduce a building's heating or cooling energy needs by about 20%, per a U.S. Department of Energy estimate. Plus, if lots of buildings in a single city adopt smart glass, it can reduce the peak load on the local electric grid during times of heavy use.

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'Smart Glass' is Coming To a Building Near You

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  • Ads (Score:5, Interesting)

    by fluffernutter ( 1411889 ) on Tuesday August 30, 2022 @11:11AM (#62836577)
    How much longer before they display ads for two minutes before you can see out the window? Bets?
  • by Anonymous Coward
    Tinting the glass darker will result in more heat absorption (dark colors absorb heat better). What they need to do is come up with a way to make the glass reflective on demand, which would result in reflecting sunlight away from the building and back into space.
    • Tinting the glass darker will result in more heat absorption (dark colors absorb heat better). What they need to do is come up with a way to make the glass reflective on demand, which would result in reflecting sunlight away from the building and back into space.

      Sounds like they're more concerned with excess heat coming through the glass and into the building, where a herd of humans are constantly fighting over a single thermostat for 2000SF of people.

      The temperature of the actual building or glass is about as relevant as the obesity epidemic forcing the inside temp down to 70 degrees.

      • by ShanghaiBill ( 739463 ) on Tuesday August 30, 2022 @12:46PM (#62836989)

        Where I work, we put all the cold-preference people (mostly men and fat women) in one area and all the warmth-preference people (mostly women and skinny men) in another area, regardless of job description.

        Not only did the "thermostat wars" end, but inter-departmental communication improved as salespeople sat close to developers.

        Another cost saver was to put skirts on women's desks with under-desk heaters to warm their legs, and small fans under men's desks to cool their legs.

        Of course, an even bigger money-saver was to switch to 4:1 WFH (WFH 4 days per week, WFO 1 day per week).

        • by Jhon ( 241832 )

          "Another cost saver was to put skirts on women's desks with under-desk heaters to warm their legs,"

          Wouldn't that be like running a hair dryer under everyones desk in that section? If we're talking about 4 or 5 people, probably not that big of a deal... but still -- a space heater under so many folks' desk? If they went cheap, that's a scary fire-hazzard. What kind of heaters are these? Ceramic? With auto-shut off? Because an ungodly percentage of folks will leave it on. 24-7-365.

          • Yeah, I'm surprised this was even allowed. Most office buildings prohibit space heaters for direct fire hazard reasons and also because most cubicle farms don't actually have enough electric capacity to support very many of them on a single floor plan.
          • What kind of heaters are these? Ceramic?

            No, not ceramic. They are made of fabric. You can see them here [amazon.com].

            With auto-shut off? Because an ungodly percentage of folks will leave it on. 24-7-365.

            Yes, they have timers and shut off at the end of working hours.

        • by AuMatar ( 183847 )

          Salespeople sitting close to devs is the worst thing you can possibly do for developer productivity. Devs need relative quiet. Salespeople are talking all day- its their job to talk all day. Those two needs are in direct opposition. Putting devs next to sales people is a great way to cut your devs output by half, from experience.

          • Or perhaps half their output in this case results in twice as much revenue because their efforts are better aligned?

            • by AuMatar ( 183847 )

              Yeah, that's not what happens. Ever. Any small gain from that (which realistically should be 0 because there should be an entire product management team in between rather than having sales directly interacting with engineering in a day to day manner) is dwarfed by the loss in concentration by the engineers. The only way this could not be true is if they were one of the worst run companies in the world to begin with.

    • The reflective metal layer of tinted glass makes the glass appear darker.
      • by hey! ( 33014 )

        Well, not necessarily, because you could, I suppose, make the windows completely opaque, which may have useful applications other than thermal management. But let's assume for the sake of argument that the opacity of this technology isn't quite as high as simple reflective film; it's still advantageous to be able to turn the opacity off, e.g. in the winter when solar warming is desirable or in the late afternoon where solar heating isn't as big a deal, particularly on the east side of buildings.

    • by mistergrumpy ( 7379416 ) on Tuesday August 30, 2022 @11:31AM (#62836683)
      There are several different types - for the energy saving application, the apparent tinting is actually an increase of the reflectivity of the exterior surface of the window, rejecting much of the solar IR load. Oversimplified journalism strikes again.
    • by awwshit ( 6214476 ) on Tuesday August 30, 2022 @11:31AM (#62836687)

      https://www.builderspace.com/w... [builderspace.com]

      https://info.glass.com/underst... [glass.com]

      The blocking is done at the outside pane, insulation provided by air space and the inside pane.

      • The blocking is done at the outside pane, insulation provided by air space and the inside pane.

        That works in the summer to keep the building cool.

        In the winter, it should be reversed. The inside pane should absorb the sunlight to heat the building while the air gap and outside pane insulate.

        • by kqs ( 1038910 )

          Sure. Or, you know, just let all the light in during the winter (as in TFA). This will warm the floor, which will evenly heat the room better than warmth captured near the top of the window. No need to make this more complex.

          I'm looking forward to these windows.

    • by hey! ( 33014 )

      Well, yeah, but half then the glass is going to radiate that heat, half of it toward the outside; possibly more if it's double pane. So the question is whether having the building's surface absorb and reemit energy yields any kind of net energy savings over having the building's interior absorb and reemit energy. This is the kind of question that could provoke a handwaving argument between armchair physicists here, but fortunately I can resolve that question, having read the f'in article summary. There's

      • Re-radiation by photons at any temperature people want to be around is pretty darn small. You definitely want windows to block thermal conduction. What's nice in this case is you can pick whether they reflect or transmit the IR (while still transmitting at least some of the visible and reflecting most of the UV)
      • by Rhipf ( 525263 )

        Google "passive solar heating". Glass windows aren't heating the homes and offices by transmitting heat into the buildings they are heating the spaces via solar radiation converting to heat and radiated when they strike internal surfaces. That heat is then blocked from leaving the space since glass isn't a very good conductor of heat and the insulated walls are even worse at letting the heat escape.
        These "Smart Glass" windows aren't blocking heat they are blocking light.

    • by tragedy ( 27079 )

      Tinting the glass darker will result in more heat absorption (dark colors absorb heat better). What they need to do is come up with a way to make the glass reflective on demand, which would result in reflecting sunlight away from the building and back into space.

      It all depends on where the absorption happens. If it happens after the light has passed through the glass into the building, then the heat is trapped inside. If it happens on the outermost pane of three pane windows, most of the heat you would have gotten is ultimately rejected.

      I have to say, while this may not be a terrible idea, I would be more comfortable if the grant worked for any equivalent method of reaching the same energy savings. For example, automated shutters. Or how about a rolled up, transluc

  • Tint - solid colors? (Score:4, Interesting)

    by nightflameauto ( 6607976 ) on Tuesday August 30, 2022 @11:24AM (#62836651)

    I'd like two things with smartglass.

    First? Color choice. What would be ideal would be the ability to transition between white or black, and various shades of gray. If they want to include other colors, cool, but white and black and the two I'd want. White for summer (reflect heat and light) black for winter (absorb heat and light).

    Second? Not just tints. Blackout (or whiteout) completely. Why? We have dogs. If the little bastards couldn't see out they'd stop barking at every neighbor, every other dog, every squirrel and every waving blade of grass they happen to see when laying with their heads in the window.

    • We have dogs. If the little bastards couldn't see out they'd stop barking at every neighbor...

      We have a shih tsu, and our neighbors had several german shepards. (I write "had," because they've moved away, along with their dogs.) Their dogs would yap at anything that moved, including each other, and our dog would run over to that side of the house and yap back, even though she couldn't see the other dogs or what they were yapping at. Dogs don't need to see something to bark at it, they just need to he
      • Our dogs are instigators. One likes to lay with her head right in the window so she can see things. And she'll announce everything from a bird flying by to a piece of garbage getting blown across the driveway. I'd say blackout windows would give us about a 75% reduction in unnecessary yapping, perhaps more on a good night.

        • Or you could train your dogs not to bark?

          That's what responsible dog owners do. If you think you can't train your dog, the problem is most likely you and not your dog.

    • by Kaenneth ( 82978 )

      building window glass is usually two layers; shouldn't be too hard to make the outer layer clear/white, and the inner layer clear/black, then you can switch them as needed.

    • by tragedy ( 27079 )

      We have dogs. If the little bastards couldn't see out they'd stop barking at every neighbor, every other dog, every squirrel and every waving blade of grass they happen to see when laying with their heads in the window.

      Maybe, but wouldn't they just bark at every single sound or smell they got from outside instead?

      • They do that already. This would just be removing one potential stimulus. We'd need to soundproof the house to get them to stop completely. Considering how often they lose their minds for a neighbor daring to step outside their house, I'd consider it a positive step to blackout the windows on cue.

        • by tragedy ( 27079 )

          You really might want to consider bark collars. They're not so bad. I've tried one on the highest setting and it really just felt like getting a little slap on the throat with a ruler. Of course, I realize that barking at things might be the dogs favorite activity and you might not want to take that away from them. There are various ones that come with remotes, timers, what have you though, and it should be quite possible to train them to understand when the collar is turned off and they're free to bark or

          • I would, but attempting to discipline the dogs leads to spousal disagreements. Strong disagreements. Because they're so precious and special and stuff.

            I mean, I love the little furballs, but there are times I think it's OK to say, "Yo, stop it." She doesn't.

  • The IRA? (Score:2, Funny)

    by ickleberry ( 864871 )
    Great to see they have gone from bombing buildings to installing smart glass
  • by packrat0x ( 798359 ) on Tuesday August 30, 2022 @11:29AM (#62836671)

    Saw this technology in 1990. There must be other factors why it hasn't been widely deployed: installation cost, cost vs benefit, fire safety, impact resistance, longevity (mean time to failure), ease of repair/replacement, recyclability, etc.

    • by rgmoore ( 133276 )

      I think the main reason is still cost. I've looked at smart glass for some of my windows, and it's still expensive. It's probably a money saver overall, but it's a classic problem with this kind of thing: a big up-front cost and a long, slow payback. If they can use subsidies to get more people to install it, the costs may come down. That would lead to a virtuous cycle where increased sales lead to reduced unit costs, which lead to even more increase in sales.

    • by lsllll ( 830002 )

      So, I can shed a little light on this as I recently redid my bathroom and my shower was moved to where there's a double window. The plan was for privacy glass. As such, I pulled 16 gauge wire to the two sides and went to task for finding privacy glass for 2 windows, each 25 3/4" x 48 3/4".

      I found a local vendor who would change the glass itself. They wanted $5000+. Out of my price range. My next option was privacy films, which are put directly on the existing glass with a small channel on top to run th

    • by AmiMoJo ( 196126 )

      The older tech had issues. With electrochromic glass there was a tint, and the transition was quite slow (several minutes). Newer tech has fixed those issues, but because high voltages are required (100V+) it needs to be built into the glass for safety reasons, i.e. it can't be retrofitted.

      There is also LCD, which is safer and relatively cheap. It just goes dim though, it can't offer a mirror finish and like normal tinted windows is still somewhat transparent even in the dark state. The other issue is that

  • by organgtool ( 966989 ) on Tuesday August 30, 2022 @11:47AM (#62836773)
    The thing I don't like about these windows is that almost all of them require a constant source of power to keep the tint activated. Could they use something like e-ink so that they only need to be powered when changing the level of tint? That would also keep the building a bit cooler if it looses power in the summer.
    • Large format e-ink is one of those really neat pieces of tech that has never quite made it to the mainstream.

      You can find some products out there in the 30-40" size range but it's pretty uncommon, i'm not sure due to issues with scaling production or patents or just lack of demand, it's just never made it out of small displays and e-reader territory.

    • by bws111 ( 1216812 )

      E-ink is made up of cells containing white paint and black oil. Depending on the charge applied, you either see the paint or the oil. It is never transparent, so would be useless for windows.

      • E-ink is made up of cells containing white paint and black oil. Depending on the charge applied, you either see the paint or the oil. It is never transparent, so would be useless for windows.

        Depends. While it's not optically transparent, translucent has a place like in skylights, yes?

        • by bws111 ( 1216812 )

          But it is not translucent. Each micro-cell has a black side and a white side. A momentary charge flips the cell so you are looking at the desired side. You are never looking 'through' the cell.

  • How about some blinds?
  • They'll never catch on, no matter what the benefits may be. Energy efficient? Smart?! That's un-American! They need windows that lose heat in the winter & heat up the inside of buildings in the summer & that are big, heavy, expensive, poorly-designed &, most important of all, dumb. God bless 'Murica! FREEDOM!!
    • If this were cheap and didn't have drawbacks, it would be used; companies want to make money. Were there other countries that adopted this technology without incentives? No? That's because it didn't make sense to invest in it for individual companies, nothing to do with America.

      I hate this demonization of 30% of the country by another 30%, in both directions. I think the 40% of independents should come out against the 60% and unite them.

  • I'll bet graft is her middle name.

    https://readsludge.com/2022/07... [readsludge.com]

  • Can't have direct solar heating if the sun doesn't hit the window in the first place. But no, use the window coated with some weird toxic bullshit that they'll figure out was a horrifyingly bad idea in 30 years.

    • So you'll have hot awnings and porches surrounding your building; what a genius you are. No real estate for that stuff in large cities anyway

  • We have a sliding glass door on our house. It's got internal shades that need replacing, and just for giggles looked into replacing with some sort of electrochromic thing.
    $2500 for DIY window film.

  • Slow glass (https://en.wikipedia.org/wiki/Light_of_Other_Days) would be even better; you could have the winter light come through the windows in the summer, causing less heat, and the summer light come through in the winter. You could also offset the time by twelve hours, but that might be inconvenient for sleeping.

  • A better way to save building energy would be to install
    electically operated shutters that would block direct
    sunlight while leaving the view open to daylight.

    You could also install solar panels on those shutters.
    If the energy generated that way were only used
    to provide extra energy for summertime air conditioning,
    they would pay for themselves in a few years
    while saving a huge amount of energy over the lifetime
    of the building.

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