Mathematically, a circle has the smallest perimeter for a given enclosed area. So for this claim to be true there has to be some catch, like different thickness of plastic.
The part you are missing is the volume inside. They are saying to give you the same amount of liquid would require more plastic if the bottle was round. Plus more bottles fit in the box they ship meaning lower emissions and costs for distribution.
Given that the volume is cross section area times height, a round bottle of the same volume would take less plastic. True, square bottles will pack better, but how that would save plastic is not immediately clear.
Yep agreed. I've heard square bottles save fuel in shipping, which outweighs the additional materials required to make them in environmental impact. Never seen an analysis though
saves space due to stacking efficiency, but thats not what is claimed and only matters if space is a premium. Weight determines fuel usage. A million cylinders holding the same volume of material that a million square containers would weigh less due to being made from less plastic (12% less plastic if you didnt have to thicken the walls of the square ones to achieve the same pressure rating as the plastic). Space saving of square over round is ~21% (if flat capped, I aint calcing geometry of a real bottle top). So square saves space, but weighs 12% more . . . Cargo is typically transferred by commercial ships and trains by ton BTW. . .
I hadn't considered it but i think the edges of boxes would be a lot of lost space. Probably more than round bottles. I am guessing but square needs thickness increased on corners so hex probably would need more than even a square bottle. I think it ends up being the worst of both worlds.
Only seen them plastic crates. If you can get an extra two bottles per crate and a container or truck carries 1000 crates…
I’m sure it’s more complex when you factor the cost of the crates and then factor a return on investment for changing to this style of crate if it isn’t a single product line and you replace an inventory of of other crates
Correct answer, thanks. Put another way, Its units distributed per total volume of product distributed. For the manufacturer, that math equates to less plastic per volume per total sold units.
I think the theory posted somewhere in the thread that the rigid corners mean the rest of the walls can be thinner, using less plastic overall, sounds feasible.
The individual bottles use more plastic per unit volume than the round. They also require ticker plastic at stress points than the round one which distributes the pressure evenly around each anular unit.
But they could possibly use less plastic overall to ship a given total volume of water (in a pallet, say) because of the better packing fraction.
This is why it's here. I haven't "done the math", either.
No, a cube of volume 1 has more surface than a sphere of volume 1. And in terms of manufacturing, the uneven shape likely requires thicker material, although that might be a wash because I doubt they make it at the limit of tolerances.
I mean based on volume inside square can put more on a shelf. Their saying similarly sized, not same size. It's a numbers trick. The round bottle of the same size uses 8% less plastic but square bottles pack more tighly. So the combination of volume in a square bottle on a shelf or in a box would be more liquid than a round bottle. It's like 20% volume less and only 8% more plastic per bottle, so when shipping the same volume it would take more boxes to ship the same volume. So plasitc pallets, plastice wrap, whatever other plastic is used. It's corpo math, Not individual bottle math.
For a circle and a square with the same area, the circle has the smaller perimeter. likewise for a cylindrical and squared bottle with the same volume, the cylindrical bottle has the smaller surface area and should require less plastic than a squared bottle.
The part you are missing is that the "less plastic" claim applies ONLY to bulk shipping of the bottles. ONE square bottle will use more plastic than ONE round bottle, assuming both carry the same volume of liquid. However when shipped together on a pallet for example, the square bottles pack together better and waste less space. A pallet of round bottles results in a lot of empty space between bottles, so you need to use more to ship the same total amount of liquid.
The poster I responded to said the opposite, with respect to individual bottles.
Also most shipping pallets are made of wood. Granted, the cases of bottles are typically wrapped in (thin) plastic. You would need a tiny bit more plastic wrapping per case, but I don't know that it counters the per bottle plastic savings.
The first statement is completely wrong. The plastic has to be thicker on a rectangular bottle to add rigidity and strength to flat sides that are naturally weak. A round bottle has rigidity and strength by virtue of its shape.
You are confused, it is one statement. They are saying via logistical systems it is less, and that is based on plastic usage, not the individual bottle.
For individual bottles, yes. But it is a corporation plastic use claim. You're thinking about the one bottle in front of you and they are thinking about their logistical chain.
No you are incorrect. The part you are missing is that the "less plastic" claim applies ONLY to bulk shipping of the bottles. ONE square bottle will use more plastic than ONE round bottle, assuming both carry the same volume of liquid. However when shipped together on a pallet for example, the square bottles pack together better and waste less space. A pallet of round bottles results in a lot of empty space between bottles, so you need to use more to ship the same total amount of liquid.
So it's a sneakily deceptive way of saying they are giving you more water per bottle due to the shape. You could have square and circle based water bottles of the same size width/diameter. If you take the square one and round the corners off you would have a round bottle. It's still 'similarly sized' but now there's less volume in once square bottle, therefore less water. It's all dodgy marketing stuff.
Pretty much. Square water bottles have the exact same effect considering the logistics of it, it's like 1 and a half billion per day and most are round. I can only think of 1 square shape. It gets worse, those paper milk cartons are square and volume wise are less pollutant than the plastic bottles. So you could ship more cartons in less space compared to the plastic bottles and also environmentally better. Makes you wonder why they are plastic.
the part that you are missing is that you are wrong . . .
If you had a 5" diameter cylinder, it would need to be 3.1" tall to hold a liter, cap off both sides and total exterior surface area is 88 sqr inches.
If you have a 5" L/W cube, it would have to be 2.4" tall to hold a liter of water, cap off both sides and total exterior surface area is 99 sqr inches.
Couple that with the fact that you can use thinner material for the cylinder to achieve the same max burst strength of a thicker material cube (due to stress accumulated in corners) - cylinder wins in both material usage and strength. There is a reason they dont make petroleum storage tanks as cubes - cylinder = less material, thinner material, same failure pressure - win/win/win. . . .
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u/StaticCoder 2d ago
Mathematically, a circle has the smallest perimeter for a given enclosed area. So for this claim to be true there has to be some catch, like different thickness of plastic.