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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

#201

Post by stackghost »

shrx wrote: post #100
landl0rd wrote: post #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…

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?" ;)

Aviation is notorious for having long product cycles. Look at how long GA pilots have been spraying their communities with lead.

There's simply no economic feasibility to replace every seal on every aircraft.

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

#202

Post by parimm »

Part time coconut farmer here.

Adding some numbers for a base line. (Note all of these numbers are almost the upper limit of a well managed farm with very good cultivars)

Best yielding palms yield ~300 nuts per pals at 70 palms/acre.

at 750g a dehusked nut with 20% oil yield

You get ~2.3 tonnes oil/acre.

For reference an a321neo burns around 2,300 kg of fuel per hour when cruising

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

#203

Post by b112 »

Retric wrote: post #142
WalterBright wrote: post #135

Earlier quoted context omitted.

Potato ------ Prep: 5 seconds under the faucet, 10 seconds to quarter it Cook: 3 min 40 sec in the microwave TV Dinner: 10 min in the microwave, $7.69 price

You’re undercooked your potatoes the goal isn’t simply to warm them, but allow your body to more easily digest them. But this isn’t just a me thing: https://www.bigbearswife.com/how-to-cook-a-potato-in-the-mic... How long does it take to cook a potato in the microwave? Between 5-10 minutes https://microwaveshub.com/how-long-to-heat-up-a-potato-in-th... The cooking time to heat a potato in the microwave will largely d…

Wait why are you guys cutting the potatoes up before putting them in the microwave? Steps:

* Wash in water

* Cut out any bad parts

* Stab the whole potato with the fork a bunch of times

* Nuke until gushy

A few medium sized potatoes will take maybe 8 minutes to cook all at once here. That's not really an issue of course, as you'll cook a small piece of meat in a pan, which takes about the same time. EG, you start the pan heating, while taking 2 min to defrost the meat, and you're prepping the potatoes. Then meat in pan, potatoes in microwave, they're done mostly at the same time.

Note you don't need to completely defrost the meat. It doesn't matter if it's -5C or +5C. A "little" frozen is fine, especially for steak which can be rare inside. Anyhow. Sorry to interject, but the potato thing is weird to me.

The article, I just noticed, does cite the fork.. but talks about exploding? No, it won't explode, the fork instead allows for an evener cook.

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

#204

Post by b112 »

rotringlvr wrote: post #108
WalterBright wrote: post #98

Earlier quoted context omitted.

I bought over a pound of steak the other day for $5. (Yes, it was on sale. But it is frequently on sale.) Along with a potato for 50 cents, that's cheaper than a bag of Doritos. Oh, and I bought a banana for $.22. Cooking a steak takes about 10 minutes. Microwaving a TV dinner ($7.50) takes more time.

When I was a grad student, I pointed this out to my poor neighbor with lots of health problems (5 pills a day!) who was shocked that I ate such expensive food despite being poorer still. 15 years later she's 50 lb lighter, takes no daily medication, and we have a mortgage and three kids. That's right, I fixed her up and married her.

It has been my experience, as a general rule (so it may not apply here), that people who grow up in the city are the worst at this.

People with strong rural roots, or who grew up in rural areas, tend to have lived in houses, have freezers, space for long term storage of items, and may have personal knowledge of canning, and food storage. If one grows up in an apartment, there may not be space for a shelf with canned food and bags of rice and potatoes.

I find that during harvest times, last year's canned foods are marked down. The logic being, I think, clear out their warehouses and get people to take last year's stuff home. And if you have space, you can take advantage of such things, and save, save, save.

For food, poor rural people often have better outcomes than city folk, due to the ability to store when sale items are found.

So when I read stories such as yours, I always wonder. City girl? Country boy? And as I said at the start, this is not a hard fact, just something I've noticed being a common reason why some people just "don't know".

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

#205

Post by skew-aberration »

somenameforme wrote: post #192
bawolff wrote: post #110

Earlier quoted context omitted.

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

The largest private single owner of farmland in the US is Bill Gates. [1] He owns [1] - https://nypost.com/2023/11/25/business/how-bill-gates-quietl... [2] - https://www.nass.usda.gov/Publications/AgCensus/2022/Full_Re...

How does that account for corporate owned farmland though?

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

#206

Post by Walf »

stuaxo wrote: post #158
panny wrote: post #119

Earlier quoted context omitted.

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.

Fair play, also we need to stop using palm oil in food.

But how else am I going get orangutan flavour in my ice c̶r̶e̶a̶m̶ confection?

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

#207

Post by jeffrallen »

parimm wrote: post #202

Part time coconut farmer here. Adding some numbers for a base line. (Note all of these numbers are almost the upper limit of a well managed farm with very good cultivars) Best yielding palms yield ~300 nuts per pals at 70 palms/acre. at 750g a dehusked nut with 20% oil yield You get ~2.3 tonnes oil/acre. For reference an a321neo burns around 2,300 kg of fuel per hour when cruising

Top comment is a chemist explaining aromatics and seal compatibility. Fourth comment starts with "part time coconut farmer here".

I <3 you HN, never change.

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

#208

Post by jeffrallen »

chr15m wrote: post #188

Around one million coconuts required to fly from Tokyo to Los Angeles. Around 40 million flights per year. 40 trillion coconuts required for all flights, or 1000x current production. To scale up coconut production we need 12 billion hectares, or 80% of the Earth's surface for coconut trees. We need 100k cubic km of water per year, or twice the renewable fresh water on this planet. Ok cool. We will need to terraform M…

The O in "occupy mars" is actually a coconut.

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

#210

Post by europoorean »

bawolff wrote: post #110
europoorean wrote: post #57

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?

I don't (or didn't) know the answer to those questions.

Regarding corporate farms, they may actually be some of the most productive farms, and give people actual opportunities to find good jobs in farming (that donmt require that they inherit a farm from mum and dad).

If you manage to tolerate the interviewer, I think the person being interviewed here was very interesting, and made me think about corporate farming in a different way:

https://youtu.be/pgdLYugmkX8

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