Off-topic, but related to your post. When I found out hp.com had a website at www2.hp.com I thought I had discovered the second world wide web, and I tried to go to every single other domain I knew and add www2 in front in hopes of finding out more about this second world wide web.
Most people aren't aware that the difference in energy efficiency between glass and aluminum recycling is enormous. Here are some choice quotes from National Geographic...
"each 10 percent of cullet in the mix reduces the energy required to make new [glass] containers by 2 to 3 percent"
At 70% cullet (the max), that's only 14-21% in energy savings for glass.
"creating an aluminum can out of recycled materials requires only 5 percent as much energy as creating a brand new can from bauxite ore"
That's 95% energy savings for aluminum. Big difference!
Thanks for that. I learned that it's very likely that most of the stuff I put in the bin is actually recycled (except, it seems, for some plastics). I had been skeptical.
You can find a whole days worth of entertainment by simply searching on "how X is made". Discovery Channel has a lot of entries on youtube as do other producers of similar content.
I am always fascinated by how air is used in sorting various items, from the colored glass in this application to even filtering out bad potato chips.
Glass bottle recycling could be much more efficient if we (in the US) still did what we used to do: wash and sterilize the old bottles and then reuse them. (of course, collection costs might also be higher since you need to get used bottles back to the right bottler without damaging them).
Some dairies do that, by including a $1 deposit on bottles. At $1, it's actually worth your while to collect and return the bottles to the store where you got them (likely when you go shopping for your next bottle of milk).
Norway has a bottle tax ranging from 0.5 to 2.5 NOK I think (been a while since I lived in Norway; 2.5NOK is roughly 43 cents), and a recycling rate for glass bottles of something like 99%.
The key, in addition to the bottle tax, is automated bottle collection machines in pretty much all grocery stores that'll issue receipts to be used to offset against purchases at the till. It's so convenient most people return them, and the bottle tax ensures most of those that gets thrown away gets picked up by kids or poorer people for the money.
Most undamaged glass bottles would be returned to bottlers by volume rather than origin, for washing and reuse, apart from Coke bottles for obvious reasons.
Though these days most of the bottles are still plastic, but are still largely recycled - even if the energy savings isn't all that huge, it still saves a lot of landfill space.
In Germany shopw have to charge you 25 eurocent when you buy a plastic bottle which they will return when you bring the bottle back.
No such thing exists for glass bottles but they do get recycled. There are even separate recycle bins for white, brown and green glass. Yes, germans take trash separation seriously (on a related note, people in Japan too).
I think you’re missing the point. It’s ‘reusing’ versus ’recycling’. When you throw bottles in a recycling bin, you can’t reuse them because they’re broken. It then takes a lot of energy to turn them into new bottles. It’s a lot better to keep the bottles intact, clean them, and fill them again. That’s what a few countries have chosen to do. The way it’s done in Germany is unfortunately a lot more common.
Everything that you buy per crate is usually returned as a a crate with empty bottles again. Case in point: beer bottles.
Depending on brewery and type of bottle, I used to get beer that had the name of another beer printed on the (non-removable) snap-lock cap[1]. The same goes for a variety of other glass bottles. They are simply washed out (usually chemically), refilled, a new printed label is put on, a cap put on, done.
Denmark has these machines also, but I believe the vast majority of the bottles are now crushed anyway, rather than reused. The traditional standard bottles, mostly nowadays used by lower-end beer and soda manufacturers, are reused (you can tell by the scuffing around the middle of the bottle on reused bottles). They're made of thicker glass and are in a standardized shape. But most beer comes in bottles with thinner glass and unstandardized shape. I believe that started due to the EU ruling that Denmark's requirement for standardized bottles was de-facto a trade barrier, since it made it difficult for non-Danish beer manufacturers to export to the Danish market.
I knew this was working in Norway when the morning after some festival I saw young people use a small boat to gather all the bottles and cans in the nearby lake :)
In my town you can arbitrage them by buying quarts of yogurt at the farmers' market where the deposit is $1.25, and returning the bottles to the grocery store, that carries the same brand of yogurt in the same bottles, where they pay $1.50 for returns.
Reminds me how food stamps can be used to buy soda. Some people who had more than they needed would buy soda, pour it out, and return the bottle just for the deposit.
They fixed that by making the deposit not payable by the food stamp.
This sounds great, but would actually hurt the environment, not help it.
Of all the things on this earth to recycle, glass is the very last one. The planet (the crust anyway) is basically made of glass. (60.2% of the earth's surface, by mass, is glass.) It's, by far, the most plentiful raw element there is. Next closest is alumina at 15.2%.
Recycle it for some energy savings? Sure. But if you are going to waste water, and heat, for it you are really doing exactly the opposite of saving energy - not only are you wasting energy, you are wasting water, and time.
Pretty much the only things worth recycling are metals.
Glass is not an element. Neither is alumina; alumina is a compound of two elements, aluminum and oxygen. Glass is a kind of solid which can be made of virtually any substance, including water, steel, and alumina. Very little of the earth's surface is actually made of glass (although some is: pumice and obsidian are glasses) but all of it could be made into glass.
It's true that every recycling process uses energy and other resources. That's why the first choice is "reduce" — read your neighbor's newspaper instead of just sending it off to be pulped. The question is how much energy you're using, and how much the alternative non-recycling process would use.
If you're comparing heating a bottle from 20° to 73° to sterilize it and heating it to 1400° to melt it, you will find that melting it uses, unsurprisingly, about 30 times as much energy as sterilizing it. It's going to take a heck of a lot of water desalination to make up for that much energy.
(When I said element I didn't mean it in it's chemical sense, but rather in the composition sense.) Glass is SiO2, and that is what the crust of the earth is made of. It's not amorphous, but that doesn't make any difference.
To sterilize a bottle using water you have to heat water, not just glass. Water takes a huge amount of energy to heat. Your calculations are not as straightforward as you think. Plus heating something at home to sterilize it is not anywhere near as efficient as doing it in bulk.
To melt glass takes 984.2 J/g. A glass bottle weights about 200g. So about 200kJ. That much energy will raise about 1kg of water 50 degrees.
1kg of water is about 1 liter. 1 liter of water is not enough to sterilize a glass bottle unless you had a perfectly shaped container to hold it.
So final result: melting the glass uses less energy than sterilizing it. Plus no water. Plus the glass plant can probably recover most of the waste heat. Plus no need to wash the bottle. Plus no need to sort and transport to the original location.
And now you know why almost no one does it: It's a bad idea.
You're assuming the only energy in reforming a glass bottle comes from melting the glass and that industrial sterilisation submerges a bottle into fresh hot water, neither of which is true.
As far as I know, industrial sterilisation uses very high pressure, high temperature steam or UV light for smaller operations.
You still have to wash the bottle, and that's done with hot water. They probably make the homeowner do that, otherwise they would have some very dirty and stinky bottles by the time they got to them.
That single action alone tips the energy balance, even before you go any further. (But of course the bottle maker doesn't pay for it....)
I bet the steam is not recaptured because it prevents continuous operation of the line (you would need a pressure chamber with some kind of airlock). They probably do a batch, then open it and let the steam escape.
So your steam is still very energy intensive, (and if you can recapture the heat energy in waste steam you can also do it for molten glass).
And even if you got the energy stuff settled (which isn't going to be easy) this might work (barely) for high volume daily deliveries (milk is the classic example), but it would be hugely labor intensive for any other purpose - and labor also costs energy.
If you're washing a sink full of bottles, you're probably doing it in water that's around 45° (which you had to heat up from, say, 20°) and you're probably using more like a cup of water (250ml) per bottle, not a liter. I mean, my sink won't even hold 20 liters of water. Even if that water isn't usefully warming up your house, we're still talking about (45°-20°)×250ml/bottle×1 calorie/ml/° for more like 26 kJ per bottle.
As for the steam, you only need enough steam to fill the bottle — perhaps one gram of steam per bottle, or a bit less. That costs you on the order of 600 calories, or about 2.5 kJ. Actually heating the bottle itself at 0.84 J/g/° will cost more than that; say that instead of heating to 73°, the minimum standard for food sterilization, you heat it to 150° with high-pressure steam. That's (150°-20°) × 200 g × 0.84 J/g/° = 22 kJ.
So, assuming batch autoclaves like you said, with much higher temperatures than needed, with people washing their bottles at home in the sink, we have an energy cost of 26kJ + 2.5 kJ + 22kJ = 50kJ per bottle, compared to the 200kJ you calculated to recycle it. And that's why glass bottle reuse is widespread, even if perhaps not in your neighborhood: it saves energy. In my neighborhood, it's basically universal. Beer is always bought in returnable bottles here, and soft drink glass bottles are usually returnable.
Why might it not be widespread in your neighborhood? Aside from the water-heating externality you suggest, I suspect that it's because you guys are spending extra energy to reduce labor costs, because labor is expensive where you are, especially when doing the labor means you have to deal with dirty, stinky bottles — even if occasionally.
On the other hand, basically anything you do with a plastic bottle — whether you return it for reuse or throw it away, both of which are common in my neighborhood — is going to cost a great deal less energy.
By the way, I'm really delighted to have a conversation here on HN that involves actual facts and calculation, along with careful consideration of the possibilities. Thank you for that.
I have some issues with your numbers. (I hope you still read this thread a day later.)
First where I live water is about 4-10 degree C, not 20. So that bumps your water heating energy (assuming your 1/4 liter volume is correct) to 43kJ. But washing dishes uses about 20 gallons per sinkful. Say a sink can hold 8 bottles, that means you need about 9 liters of water per bottle to wash it - not a 1/4 liter. (A dishwasher is much more efficient BTW.)
So 43kJ * 36 = 1548kJ.
At 150 degrees a 1 liter bottle needs 2.6 grams of steam to fill it. (Density from http://www.engineeringtoolbox.com/saturated-steam-properties... at temperature of 150.) And using my number of 4 degrees for incoming water, your energy use is 2261 kj/kg * 2.6 grams = 5.88kJ.
So your total is 1548kJ + 5.8kJ + 22kJ = 1576kJ vs 200kJ. i.e. it's not even close.
A dishwasher uses 4 gallons per load, and you can fit about 20 bottles in there. Which is .75l per bottle - way better than by hand. Using those numbers your total is 157kJ per bottle compared to 200kJ.
So it's ever so slightly better - but of course we are ignoring transportation and sorting costs. Not to mention the factory for sterilizing bottles. (You anyway need one to make glass and bottles, to reuse them you must build a whole new factory.)
And the real kicker is the extra water. Currently the world has enough energy, but not enough water. (Maybe we should calculate desalination costs for the water and bundle it into the energy budget.)
Where I live the temperature of the water is about the same as the temperature of the air, which typically varies between -10° and 40° in human-inhabited zones. But the main point here is really that what matters is how you wash the bottles: if you wash them in running hot water, which I think is what you're talking about when you say "20 gallons per sinkful", then you get megajoule-scale numbers. If you wash multiple sinkfuls of dishes with a sinkful of dishwater, you get a number lower by a factor of 20, like I did. And if you wash your bottles in cold water, you get even lower numbers.
In my previous comment I was tempted to suggest washing in salt water, but ① very few people do that, and ② it's a pain, because the salt makes the soap stop working.
Desalination turns out to be a reasonable cost, but still one that tips the balance in favor of recycling rather than reuse. Typical desalination plant costs are half for energy and half other things (like plant construction), and total about US$0.001 per liter. If we assume that all, rather than half, of that cost pays for energy, and at the typical wholesale price of US$40 / megawatt-hour, it works out to 95kJ/liter. So the answer still depends on factors like how cold your water is before it goes into the hot water heater, how much water you use per bottle, and stuff like that.
I don't agree about your factory construction line item; if you reduce the demand for glass bottles by reusing old ones instead of melting them down, you need fewer bottle factories.
> Where I live the temperature of the water is about the same as the temperature of the air
How do you manage that? By me the water comes in from underground pipes and is always the temperature of the ground, which stays pretty constant (and cold) year round.
> suggest washing in salt water
And aside from the other things you mentioned, most people don't have access to salt water. In the US it's only available on the coasts, but the coasts are usually premium land and not available for industry.
I do think we've basically come to an agreement that it depends mainly on the process used for washing the bottle.
With two points of disagreement: I still think the extra labor needed tips the energy balance away from reuse. And I think that trading water for energy is worth it.
> reduce the demand ... you need fewer bottle factories.
It's much easier to make a factory larger than it is to build a whole new one.
The machines I've seen are essentially autoclaves, so sealed high pressure chambers.
What you've expanded on is correct. The point I was trying to make was that at an industrial scale, the back of the envelope calculation you first presented isn't particularly useful in working out the energy delta between reusing vs recycling.
In the Netherlands glass bottle and plastic bottles,cost between 0.25€ and 0.50€ more, money you get back when you return them to the store. As a consequence of reciclying, the beer is usually cheaper when bought in glass bottles and beer crates (0.20€ - 0.30€ per 0.3L bottles) thus people usually buy those. It's a win-win situation for everyone :)
Only beer bottles carry a deposit (€0.10), all other glass bottles are to be disposed of in glass recycling containers (and doing so breaks the bottles). Beer bottles are the only ones being reused, not recycled.
Although surrounding countries use a deposit system for aluminum cans to combat litter, the Netherlands does not.
Also, even though PET bottles carry a deposit (€0.25), relatively few of the bottles that are returned are actually used to create new bottles. For instance, a Coca Cola PET bottle consists of just 25% recycled plastic.
Lastly, starting in 2015 PET bottles sold in the Netherlands will not carry a deposit. Next year, PET bottle collection will move from store level to the municipal level.
The whole landfill thing has always prayed on human's inability to get to bigger picture. They see a dump and somehow think it'll take over as time goes by.
Dig a hole, put rubbish in it, push dirt on top 50 years later and you get a nice park.
Don't think it's safe for humans on top, even better a guaranteed wildlife refuge.
I like the use of gifs, although it loads really poorly on my computer. Half of them don't animate, and the other ones stutter. It feels really laggy scrolling through the page.
I wish browsers could handle animated gifs better, and (from an end user perspective) make them essentially work like an embedded Vine.
The GIFs total 30MB (!), but as videos[1] they're 1-2MB total. That's a 15x-30x reduction in size.
Surely that large of a reduction in bandwidth and improvement in user experience is worth it?
[1] To get the frames of the GIFs:
for i in "* .gif"; do convert $i -coalesce $(basename $i .gif)-%02d.png; done
And encode them to webm:
for i in "* .gif"; do ffmpeg -f image2 -r 30 -i $(basename $i .gif)-%02d.png -vcodec libvpx -b 1M -crf 5 $(basename $i .gif).webm; done
I hate it. It's a lazy way to avoid editing a short video and doing some narration. This is what you get when you have cameras that record quality video on the cheap but people who can't be bothered to learn any of the technique to use them effectively.
I disagree, deeply. This is simply a different medium — this is basically an illustrated article, where the illustrations happen to contain motion.
It's not that text and video are that different in terms of information, it's that they differ in timing. For example, a narrated video will likely linger on some images, then cut to something else, and so on, all the while being edited in a particular way, with a particular tempo. And video presents only one frame at a time. With text, I can choose my tempo, and since everything is presented in two dimensions I can skip or skim much more easily.
It should also be said that text can be read much faster than a narrator can give me the same amount of information. Video is seldom information-dense (in terms of useful information, not raw pixels).
ACHILLES: You are right on both counts. But even though the record is there "all at once," as you put it, we can draw sounds out of it bi by bit. The idea behind this is that the grooves pass slowly under the needle, and as they pass, the needle vibrates slightly in response to those very fine designs you earlier referred to. Somehow, in those designs are coded musical sounds, which are processed and passed on to the loudspeaker, to dispense to our waiting ears. Thus we manage to hear the music just as you said, "a bit at a time." The whole process is quite marvelous, I should say.
TORTOISE: Well, it is marvelously complicated, I'll grant you that. But why don't you do as I do just hang the record up on your wall and enjoy its beauty all at once, instead of in small pieces doled out ove a period of time? Is it that somehow there is a masochistic pleasure in the pain of doling out its beauties so slowly? I am always against masochism.
If there had been a video with narration I would have instantly closed the page. Video is just too information-sparse.
I thought the GIFs were tastefully done, although the bottle-top making one is confusing. Still images would have been just as good, especially for the front-end loader which isn't exactly a new concept. I did like seeing the hot glass bottles visually cool down, though.
Gifs are a horrible format for video, but yet people love them for their simplicity. Vine is smartly capitalizing on this. Definitely think this was a stylistic choice here -- a narrated video is a completely different experience.
Yea, to clarify I was saying they were smart to capitalize on the simplicity of the GIF format (even though they're using movies), using a similar presentation style vs a typical movie presentation UI.
I find it much more likely they went this route for the style. The photographer for these photos is Lam Thuy Vo [1] and based on her gallery, she appears to shoot with a 5D Mark II. She is obviously comfortable with a high quality camera.
I'm fine with the shooting - you know it's good because of the framing, exposure, and other factors. It's the laziness of throwing 6 animated gifs on the same page that I find deplorable. Even a slideshow with text would have been an improvement. To me this is like offering someone 6 spoonfuls of different food and saying it's equivalent to a meal. There's an entire visual grammar of sequential image presentation that's getting thrown away for the sake of novelty, so someone at npr.org can feel hip for knowing what a gif is.
Let anyone get the wrong idea, I am a huge fan of Vine and think it occupies a happy medium between photo and longer-form video. But you won't make it better by stacking them in big piles, any more than Watching a bank of TVs tuned to multiple channels improves your information intake.
I don't know which is worse: that my computer can't load and render a simple webpage with 5 gifs, or that a webpage is so poorly optimized that it puts my laptop on it knees...
It played fine on my machine; but I have a brand new high-end laptop. It completely brought my phone's browser to a halt; none of the images animated, and it took seconds for it to respond to scroll events.
I find it odd that animated GIFs are suddenly in vogue again, right when HTML5 video is starting to become ubiquitous and is much more efficient and high-fidelity than a GIF could ever be.
Has anyone had the experience of being told to simply throw away a glass bottle - that it's essentially made of sand, and it's much more efficient just to make a new bottle from the raw material? That's happened to me, from someone working at a restaurant. I get the feeling form this (small) story, that that's not actually entirely true. What say you, HN?
I live in a rural areal, and the local recycling center recently stopped accepting glass. Apparently the cost of transporting it to someone who has the facilities to recycle it outweighs the price the recycler will pay. For a time, the city picked up the difference, but they aren't doing that anymore.
My point is that whether or not something is economic to recycle is at least in part dependent on where that thing is. I suppose it seems obvious when put that way; but I don't think its obvious at the outset.
I don't know if this is the case, but shouldn't a lot of the transportation costs be happening regardless? The distributor ships product to a store, and when they're done offloading the product, they take the recycled products from the store back to the distributor where they're headed regardless. You'd still have to transport it to a recycling center from the distributor, but I don't see why you can't build recycling centers next to distribution centers.
It astounds me that the costs of these plants (plus the costs of getting the raw/recycled material there) can be amortized to some fraction of the $2 we pay for a bottled beverage.
A few things a like that. I get 1L bottles of a tomato pasta sauce I like. It costs about US $2. It tastes good and has a custom bottle for the brand. How do they do it? I couldn't grow the ingredients from seed for that price as the seeds alone would exceed that cost. Then making the sauce, the bottle, then shipping.
but the point still stands - sure the seeds might've only cost you a few cents (or even, free if you know a nice farmer who'll give you some). But think about the time it takes to grow, and the amount of effort required to grow enough to make one jar of tomato sauce...
> (We wanted to take a picture of the furnace, but they warned us that it was so hot that getting close to it could destroy our camera lens. Which makes sense, given that it was hot enough to melt glass.)
In that case, wouldn't the furnace also be hot enough to melt the photographer?
People working near are likely to be wearing suits something like [1]. I'm not sure if there are any fundamental constraints to putting a camera inside a similar shielded enclosure, but I imagine it could be possible that the camera lenses might focus the light sufficiently to damage the CCD. Then again, the bulk of energy is presumably in the IR, which isn't particularly well transmitted through glass (and hence, would be absorbed instead, maybe damaging it or any expensive coatings it has)
If you like this you may be interested in a new waste disposal system being trialled in my city (Perth, Australia) - http://www.anaeco.com/index.php?option=com_content&task=view.... It basically takes general household garbage diverting approximately 70-85% of it from landfill. Plastics, glass, metals and biodegradable organic matter are automatically separated out at different stages and the whole plant uses biogas generated from the organic matter to generate power (excess power is fed back into the grid).
Is there a reason other than aesthetics that glass needs to be sorted? Do the chemical colorants not work well together, or is the glass types incompatible with each other?
Wouldn't multi-colored glass that looks obviously recycled be a product that would be attractive to "green-conscious" companies?
it just means that one person is capable of producing a lot more by designing smart machines, instead of manual labour. The engineering/thought going into the design is still a job.
Imagine if the entire world didn't need manual labour - what would/could happen? Is it possible that all humans work on abstract things like designing stuff (programmgin/engineering/produce entertainment for others)?
I love that the first one is named gross.gif.
Wait a minute, one of them is named opticalsorter3.gif? Why that means...
Yes! Some bonus gifs for us!
http://www.npr.org/news/graphics/2013/06/pm-recycling/optica...
http://www.npr.org/news/graphics/2013/06/pm-recycling/optica...
When I was a kid finding gems like that online always made me feel really clever.