|
|
|
|
|
by ricardobeat
1034 days ago
|
|
Sources needed. This study says paper straws uses slightly less energy and emits about the same CO2 as a plastic one: https://www.appropedia.org/HSU_straw_analysis#:~:text=A%20si.... Even if that’s not the case, “resource usage” is not the right metric to optimize for, this cost-focused mentality is exactly how we ended up with plastic [literally] everywhere. Hundreds of billions of plastic straws are thrown away every year, this is a massive problem even if its only a few % of the total. |
|
the hsu analysis is wrong because it's omitting the energy consumed by growing the trees; it rates "craft paper" as 12.6 kJ/g, but according to https://en.wikipedia.org/wiki/Energy_density#In_chemical_rea... burning wood produces 18 MJ/kg = 18 kJ/g, which is to say, more energy than that is still available in the end product, without even taking into account the "embodied" energy dissipated in processing
the energy consumed by the tree in growing is about 20× larger than this, 300–400 kJ per gram of wood, which is close to 700 kJ per gram of paper, because about half the tree is lignin, which is digested in the papermaking process and then discharged into waterways
it does give a reasonably plausible (if misleadingly precise) figure of 95.4 kJ/g for the polypropylene straws
also, it incorrectly compares 200-mg polypropylene straws against 200-mg paper straws. but paper straws are, as everyone knows, enormously thicker than polypropylene straws of the same level of durability; even with the accounting error of omitting the embodied energy of the paper, its conclusion presupposes the opposite of my premise above, which you should have mentioned in your comment (but presumably could not because you had not actually read the study you were citing)
in fact, a typical 6-mm-diameter paper straw made from 330 gsm paper at a length of 200 mm weighs some 1250 mg, roughly 6× as much as the hsu study's 200-mg estimate. a 200-mg paper straw would be 53 gsm; that's like tracing paper. it would collapse immediately if you tried to suck on it
finally, it is not correct that hundreds of billions of plastic straws are thrown away per year, and those that end up in landfills (which is the vast majority) are not a problem at all. nor are they a few % of the total, as you say, but 100× less than that; https://en.wikipedia.org/wiki/Drinking_straw#Environmental_i... says, 'In total, they are less than 0.022% of plastic waste emitted to oceans.'