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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

#112
post #100

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…

Maybe it's time to develop new sealing materials? edit: thanks for the downvote. I should've said "Maybe it's time to _invest into developing_ new sealing materials?" ;)

Maybe they should have said something like "These are solvable backwards compatibility issues, but not in the short or medium term."

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

#113

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.

Just through this out again, biofuels are dumb. Per acre a solar farm produces 30 times the energy per year as corn without most of the environmental concerns that growing corn has.

You don't have pesticide or fertilizer runoff from solar farms. You don't plow the soil resulting in soil loss.

Biofuels, dumb.

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

#114

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.

Same rural communities raise pitchforks upon mention of any other demographic receiving wealth transfers.

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

#115

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.

Yeah, I’m pretty sure it’s more of a massive subsidy to enormous agribusiness operations. But yeah I’m sure some of the pork makes its way to some normal farmers too.

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

#116
post #58

Earlier quoted context omitted.

That infographic says it uses 16-20% more fuel per unit of thrust. That's a significant amount more weight for an aircraft to carry, but because carrying extra fuel also burns fuel, extra fuel use would compound exponentially. This would probably mean significantly more than 20% extra fuel would be required for long-haul flights.

Ouch. There's one plantation of under 1000 hectares in Papua New Guinea that makes biodiesel from coconut oil to power their own operation and vehicles on the island.[1] But they don't export. On an island with few energy sources, the process makes sense. This is more like an industrial process that self-powers from its own waste. Sewerage treatment plants do that - the process produces methane, often enough to power…

^^^ this

I cringe thinking about more biofuel ideas getting forced through. Sure, let’s all spend a ton of petroleum energy on fertilizing, farm equipment, and processing, and raise food prices by using all the land for producing ethanol-corn, and jet fuel coconuts, just to get a slightly worse petroleum replacement fuel.

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

#117

Earlier quoted context omitted.

> 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.

Don't most farmers own their own farms? (or work on a corporate monstrosity farm). How common is farm landlords?

Depends on the area, but the vast majority are owner operated.

The question begs some other questions though.

One is more about what fraction of the economic production of the farm industry is owner operated; There is a long tail of now-tiny farms that are not economical to actually sow and harvest, which nobody could actually earn a living from. If it's 10 acres and somebody bales hay at almost breakeven, is it really a farm?

Conversely, there are a lot of very productive 5000+ acre farms comprised of many older properties combined together that are "owner operated" in one sense, but demand many farmhands and a lot of machinery to manage.

The vertically related industries have also seen a lot of consolidation. There are ~four seed companies, only a few pesticide companies, two main tractor companies, only a few slaughterhouse companies, etc. There are long-term contractual arrangements with some of these entities. Is an owner-operator farmer who controls so little of the business directly they may as well be a sharecropper really counted as a farm?

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

#118

Earlier quoted context omitted.

The existing solution is actively wreaking havoc on the environment. I don't know the specifics of this crop but generally agricultural products absorb a substantial amount of carbon when growing, so releasing some of that carbon by later burning has the potential to be close to carbon-neutral. Whilst petroleum fuels are 100% carbon negative.

There's more to the environment than the greenhouse effect. Coconut plantations would compete with rainforest in much the same way palm oil ones do, since they have more or less identical growing climates. If you want to use biofuels, use a plant that grows in low-value areas like open fields. Something like corn or sugarcane.

Corn ethanol is a scam and consumes as much energy to make as it “produces.” Let’s not do that either.

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

#119
post #100

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…

Maybe it's time to develop new sealing materials? edit: thanks for the downvote. I should've said "Maybe it's time to _invest into developing_ new sealing materials?" ;)

Maybe it's time to stop burning food as fuel. What are the jets going to do anyway, bomb Iranian children?

Remember when George W Bush signed into law the corn ethanol bill. Corn tripled in price within 8 years. Fuel didn't get cheaper. In fact it cost more to produce the ethanol.

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

#120

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.

They literally grow on trees
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