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Coconut oil jet fuel matches kerosene's efficiency in engine tests

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Re: Coconut oil jet fuel matches kerosene's efficiency in engine tests

#62
post #27

Earlier quoted context omitted.

> it’s led to poor use of land with questionable climate impact. In the short term, yes, because they were unnecessarily using carbon energy to grow the fuel. But if we want to de-fossilise society in the long run, we need solutions for flying and long distance travel. Electric flying seems infeasible at the moment, and people are looking for suitable bio-fuels to make flying carbon neutral. Afaik the maximum planes…

I'm not sure that mass air transit has a place in a post-oil society were we try to leave at peace with the planet. Not just for the carbon impact, but also for the diversity of our species and cultures. Should every Chinese and Indian visit Venice, even though it destroys the city little by little? Should we send things as futile as watermelons by plane? Of course, the market wills it so some may think that it must…

Why not stop other Europeans from going as well?

Re: Coconut oil jet fuel matches kerosene's efficiency in engine tests

#64

Do coconuts grow particularly efficiently? Edit: The US created biofuel subsidies a few years ago and it’s led to poor use of land with questionable climate impact. It’s effectively become a wealth transfer to support poor rural American communities, which isn’t necessarily a bad thing but there’re probably more effective ways to do that intentionally.

> a wealth transfer to support poor rural American communities My immediate reaction to this is: it's probably a wewlth transfer to the few landlords owning the land and probably charging higher rent, not to the communities. Of course I haven't analysed the data. If I am wrong, hopefully someone will feel compelled to correct me.

My understanding is that it caused the price of corn to go way up, meaning the poor in Mexico found food far more expensive.

International markets and all that...

Re: Coconut oil jet fuel matches kerosene's efficiency in engine tests

#66

Earlier quoted context omitted.

I'm not sure that mass air transit has a place in a post-oil society were we try to leave at peace with the planet. Not just for the carbon impact, but also for the diversity of our species and cultures. Should every Chinese and Indian visit Venice, even though it destroys the city little by little? Should we send things as futile as watermelons by plane? Of course, the market wills it so some may think that it must…

> Should every Chinese and Indian visit Venice, even though it destroys the city little by little? Should we send things as futile as watermelons by plane Who are you to dictate where Chinese and Indians can and cannot visit or enjoy delicious watermelons? If someone wants to eat a watermelon like a dirty slave that is their business and you are not going to deny them that right. This is pure insanity. China and Indi…

> If trains were more effective

Well they're more convenient by virtue of being faster. The well off will inevitably pay for convenience if allowed.

> If California has taught us anything it's that implementation of high speed rail is a joke.

The only thing California stands as an example of in that regard is political dysfunction. A hypothetical benevolent dictator could have built out high speed rail there on time and on budget.

> I am appalled at the level of delusion and craziness in these responses

Has it not occurred to you that maybe that's a red flag that perhaps your own views or emotional state are a bit off?

> on account of dubious climate histrionics.

An empty dismissal of a vague and poorly defined (on your part) concept. How about engaging with a real position instead of name calling a straw man?

> Ditch smartphones (future e-waste)

And what do you suppose the combined total environmental impact is for those globally compared to other categories?

Re: Coconut oil jet fuel matches kerosene's efficiency in engine tests

#67
This isn't proper SAF, it's basically C8/10 biodiesel. No aromatics which is one of the perennial problems with SAF, due not just to volumetric energy density but nitrile seals not swelling enough. Integral wing tank seals usually expect aromatic exposure also. This is why some of the catalytic routes/CHJ are of greater interest, cycloparaffins/napthenes recover some of this vs a more biodiesel-ish blend, but even 50% cycloparaffin doesn't fully recover swell. These are solvable backwards compatibility issues but not in the short or medium term.

More egregiously FAME is a polar solvent that eats your elastomers, even some fluoroelastomers. It will also attack your polysulfide tank sealant. The remark that it's "technically feasible" to decrease oxygen through hydrogenation is not at all sufficient. Now you're into requiring catalyst beds and a hydrogen plant which makes this much less appealing. Plus ester instability when you sink heat into fuel. Plus freeze point. This is literally a tracked contaminant banned above mg/kg levels that doesn't even have very good properties otherwise they want to run as a major constituent of fuels.

Re: Coconut oil jet fuel matches kerosene's efficiency in engine tests

#68

Earlier quoted context omitted.

The best solution to flying and long distance travel is to reduce it as much as possible. This means no more travelling for hedonistic (touristic) purposes. I.e. measures like massive taxation (also for private jets of course).

So no tourist travel for the poor or middle class, just the elite rich? And no tourist income for the poor and middle class? This is a policy only the top .1% will enjoy.

I don't support the idea as described, but playing devil's advocate presumably it would shift demand towards train and boat travel. That would push tourism closer to home and largely eliminate visiting other continents for those who couldn't either afford the air travel tax or to take several months off of work if going by boat. But it wouldn't eliminate tourism by any means. Even the poor could still easily travel the better part of a given continent.

Re: Coconut oil jet fuel matches kerosene's efficiency in engine tests

#69

Aviation uses around a million metric tons of jet fuel per day. If you thought habitat destruction from palm oil was bad, that would be nothing compared to coconut oil making up any significant fraction of jet fuel.

The question is which habitat destruction is worse? That which is already happening at scale for oil, versus what would happen if we lean into this in any meaningful way. I don't think the answer is obvious. And I think many of us are blind or numb to environmental harms of oil outside of carbon exhaust and the occasional spill, simply because we've accepted it as status quo.

An oil well is quite small Area wise compared to the amount of acreage you would need for a coconut plantations to replace the same amount of energy output.

The issue with oil is CO2 and other green house gases and then the occasional oil spill or leak. Land area wise they don’t take up much space

Re: Coconut oil jet fuel matches kerosene's efficiency in engine tests

#70
post #43

Earlier quoted context omitted.

Is it not a bad thing to encourage poor people to continue doing the thing that has apparently made them poor? It's also very not true that farmers are poor in the US (median household income about 30% greater than general population). This mindset is like a century old.

"It's also very not true that farmers are poor in the US (median household income about 30% greater than general population)." Most farmers work a "real" job in addition to the farm work. Then you also have farm workers, who do not own the farm, and they tend to be poor.

The economic landscape of farming is very bimodal. “Most farmers” (by headcount) are subsistence farmers who live in impoverished countries and don’t produce very much food because they are feeding themselves and their immediate community.

The food that people buy at the grocery store in developed countries is primarily produced a relatively small number of industrialized farming operations which are high dollar businesses.

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