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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

#171

Post by defrost »

Animats wrote: post #58
willtemperley wrote: post #41

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…

Biofuel as a side venture that makes a bit of profit / saves on a bit of fuel outlay has always been a thing in Australia also.

Currently, off the top of recent memory:

* Australia is exploring using canola to produce sustainable aviation and renewable diesel fuels, potentially creating 7,000+ jobs by 2030. - Landline (June 2025) https://www.youtube.com/watch?v=fIwsfxK6jw0

* North Queensland graziers are trialling a 10-hectare pongamia plantation to run alongside livestock. (July 2026) - https://www.abc.net.au/news/2026-07-19/pongamia-tree-aviatio...

* Agave is climate change resistant and has promise beyond just tequila - (May 2026) - https://www.abc.net.au/news/2026-05-23/australia-agave-farmi...

* Adelaide will turn 600,000 tons of forest waste into 140 megaliters of jet fuel per year, enough for 4.5M passenger seats. - (July 2026) - https://www.youtube.com/watch?v=z0u91oQ-hjY

The relative perspective on 4.5M passenger seats is that at one point in the recent past (possibly pre COVID) there were ~ 1M passengers in the air globally at any random time.

On the business investment and development side there are several operators, eg: JetZero Australia - https://jetzero.com.au/projects

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

#172

Post by Retric »

WalterBright wrote: post #164
Retric wrote: post #148

Earlier quoted context omitted.

Pot pie microwave time 4-5 minutes: https://airfry.guide/wp-content/uploads/2020/01/Banquet-Chic... As to let sit time, if you can instantly pop a potato or other food into your mouth after it comes out of the microwave you haven’t cooked it.

Marie Calenders are 10.5 min.

Nope: https://contenthandler-raleys.fieldera.com/prod/392493/1/0/0...

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

#173

Post by [deleted] »

WalterBright wrote: post #165
Retric wrote: post #150

Earlier quoted context omitted.

Marie Calendar pot pie, the instructions list 5-6 minutes of time in a microwave. https://contenthandler-raleys.fieldera.com/prod/392493/1/0/0... They do want you to let them cool, but that’s true of anything you heat to a cooking temperature in a microwave. Potatoes have the same limitations, but most people don’t include the “don’t be an idiot” instructions in recipes just cooking times.

The ones I buy say 10.5 min on the box. Shrug.

[deleted]

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

#174

Post by bluGill »

giantg2 wrote: post #43
qeternity wrote: post #25

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.

What do you mean by farmers? Of the rich farmers, yes, most do have a second job, but the farming does pay most of their income. It's not just a hobby. The second job is something that they can do in between the farm work. The other thing about farming is it's very much investment heavy. And so for a young farmer just getting started out, you're going to be working at farming and all of your income is going right back to paying things off. And so you're going to need a second job to put the food on the table for a few years. After 10 years, because of inflation, you would hope that your income has gone up while the payment you're making on existing land is kept the same, and so you don't have some left over, and so you can start only being a farmer. After, say, 30 years, most of your land is now paid off, and now you can take all that money that was going into paying off millions of farmlands, and you're making enough income that you could pay off of millions of dollars a loan, and you have no loans, and you are very well off. Of course after 30 years you're also getting close to retirement age and you're probably thinking well I'm gonna sell that farm off and now you have a lot of money that you can put into regular retirement acounts and enjoy a really nice retirement. But that means you're not a farmer and so the farmers themselves really have to live like the poor but they're on track to be very wealthy.

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

#175

Post by defrost »

fragmede wrote: post #154
xp84 wrote: post #116

Earlier quoted context omitted.

^^^ 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.

There's always the air-gasoline route. That's right! With enough chemical engineering and materials science, we can extract jet fuel from air and water. You extract out CO2 from the air, and H2 from water. You turn the CO2 and hydrogen into carbon monoxide, and then Fischer-Tropsch chemistry and some other magic gets you hydrocarbons out the other end! The problem is the economics of that process can't compete with o…

> The problem is the economics of that process can't compete with oil from the ground.

Even factoring in emissions?

Given oil from the ground is adding long buried CO2 to and steadily increasing atmospheric insulation whereas fuel-from-air is using what is already there.

Is this another example of discussions about oil not factoring in the negative externalities to make it look good?

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

#176

Post by bluGill »

abyssin wrote: post #17
wronex wrote: post #10

I think this is awesome. Anything we can do to get away from burning fossil fuel is a win in my book. I don’t know about this particular effort, but it seems to me that aviation could really need some big wins in this direction. Last I looked we still run smaller planes on leaded fuel. Crazy.

This isn’t awesome, it doesn’t work at scale and it only lets idiots ignore what should be done: leave fossil fuels in the ground, and only then do what we can with the energy that’s still available. Aviation is mostly incompatible with a sane global environmental policy.

Very few people are willing to accept a, "sane global environmental policy" if it means changing their lifestyle. Thus, anything that allows people to keep (or better yet, improve) their current lifestyle while making the environment sane, that is the one we need to be searching for.

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

#177

Post by runako »

triceratops wrote: post #157
runako wrote: post #136

Earlier quoted context omitted.

> It already takes 6 hours to fly. Add in security, checked bags, getting to and from the airport and it's close to 10 hours. 10 hours is still significantly faster than a hypothetical HSR. Remember that it would also have to stop along the way. Secon, not everyone lives/is traveling to a place that is near a hypothetical train station; you have to keep in mind that American cities tend toward sprawl. HSR leaving fro…

> Remember that it would also have to stop along the way Why? > Highly dependent on the individual & service class. There are flights that offer lie-flat seats for most of the passengers on board? I have to confess I haven't ever seen any domestic flights in North America that have lie-flat seats. But maybe I'm just poor. > But the point of this is you're actually physically there in less time. And more tired when yo…

> Why?

Because (ignoring the middle of the continent for a moment) "LA" is actually a very large area where having a single stop erases many of the advantages cited for trains. LA does not really have the sort of city center of most train-centric cities, and LA has poor public transit. On the other end, "NYC" has the same property, mostly because you would want to include people from other parts of the densely-populated region around NYC and not just make everyone schlep into Manhattan.

The ShanghaiBeijing HSR has 24 stops over 819 miles, for example. Similarly, it would only make sense for a US HSR to stop in e.g. Dallas or Chicago or other cities in between.

> I'd rather sleep during my travel and enjoy the destination than waste time recovering in my hotel room. The alternative is to waste your day flying out so you don't lose sleep.

Yeah, like I said individual preference. I don't normally want to do back-to-back redeye flights, but I have done it and am glad it was an option.

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

#178

Post by bluGill »

emsign wrote: post #105

The issue with bio fuel is the following: Due to climate change the overall area for food production in the world is shrinking. Bio fuel is directly competing with food. The solution: Ditch carbon based fuels as much as possible and replace it with electric transport. I know that it's currently unviable to use electric aircraft in almost all use cases except short range drones. But then the solution to that problem i…

The world is producing far, far more food than we need, though, so your worry is not realistic.

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

#179

Post by Retric »

WalterBright wrote: post #165
Retric wrote: post #150

Earlier quoted context omitted.

Marie Calendar pot pie, the instructions list 5-6 minutes of time in a microwave. https://contenthandler-raleys.fieldera.com/prod/392493/1/0/0... They do want you to let them cool, but that’s true of anything you heat to a cooking temperature in a microwave. Potatoes have the same limitations, but most people don’t include the “don’t be an idiot” instructions in recipes just cooking times.

The ones I buy say 10.5 min on the box. Shrug.

If that’s true you should be able to provide actual evidence of a 10 min 30 second cooking time listed on their box art.

However it’s clear that microwave meals are generally designed to have shorter cooking times for simple convenience and the underlying physics involved.

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