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Comment by michaelbrave | Hacker News Reader

There are bio-plastics(usually made from corn) that degrade fairly fast, the problem is they cost less than a percent of a cent more. This is really a thing where government subsidies that are forward thinking about the environment could help.

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> they cost less than a percent of a cent more

Citation please? I have dealt with packaging products for 35 years now and it’s expensive. In my experience anything close to what the parent poster described would result in packaging costs an integer multiple price increase per unit if biodegradable. Storage requirements would also increase because 60 days is not a long enough shelf lifetime for prosciutto or anything similar

I think they're referencing PLA, polylactic acid. It takes a while to fully break down, but it still does degrade.

https://en.wikipedia.org/wiki/Polylactic_acid

There was a piece in The Economist a couple of weeks ago about how some scientists made disposable coffee cups out of bagasse (wasteproduct of sugar production) which were basically as good as plastic on all the metrics GP mentioned but just fractionally more expensive. https://www.economist.com/science-and-technology/2020/11/14/...

Come on, be serious. These kinds of science-y puff pieces come out every day, on all kinds of topics (I can't count the number of times claims around cancer cures, fusion reactors, new battery technology that's 1000x better, etc. are made). This is one engineering group making very preliminary case (that they may have embellished for the media attention - wouldn't the first time - see: recent "life on Venus claims"). It takes time and lots of effort to figure out if this new material can satisfy all the necessary constraints in order to scale to the market.

And they ignore the viability of producing the object at scale. Making one and making one billion are worlds apart.

Are bio-plastics really a big improvement though? Growing corn burns a lot of fossil fuels. I think there's a case to be made that plastic that ends up in a landfill after few carbon emissions is better for the environment than plastic that degrades after lots of carbon emissions. Not saying that's definitely the case, just that I'm not sure it's so clear.

The assumption there is that plastic emits less carbon when it's being created than corn. Is that accurate?

There is also a land cost. I'd be surprised if we determined that plastic is better than bio-plastic, but until we are making bio-plastic with a low land footprint land will continue to be a factor here.

This might be a really stupid question, but how does land factor into carbon emission?

I think the issue isn't emissions in that case but a "amount of land space necessary for landfills for traditional plastic" vs. "amount of land space necessary for plant growth for bioplastic."

If the bioplastic growth land takes up more space by a certain amount than is used to dispose of regular plastic, that's presents its own set of issues.

I believe that pulling oil out of the ground is way less carbon intensive than growing the necessary amount of corn, and I believe plastic is made from some tiny fraction of the petroleum that isn't used as fuel, so the petroleum would be extracted anyway, but the corn would not be grown anyway. I'm assuming the actual production of the good itself is similar in either case.

In some ways, yes, and in others, definitely not. I think we'll get there: I also think some plastics are made using byproducts of fuel (gas/diesel) production, and as long as that's the case, we should probably use and recycle that (or find something else to do with it). Kind of like using every part of the animal, except with oil.

https://phys.org/news/2017-12-truth-bioplastics.html

> Growing corn burns fossil fuels

Head-scratching a bit there. Corn absorbs CO2 while growing right ?

From https://www.agweb.com/article/corns-carbon-cowboy-busts-outs... ...At 200 bu. per acre, every acre of corn absorbs 8 tons of carbon dioxide. In 2012, U.S. farmers grew almost 100 million acres of corn and absorbed 800 million tons of carbon dioxide...

Tractors, combines, trucks - there's a lot of heavy equipment that gets used to grow corn, and then there's emissions related to both producing and applying fertilizers.

There's the old quip that corn is just one small step in the chain of converting oil into something people can eat.

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