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

studyfinds.com

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

#51

Post by toomuchtodo »

runako wrote: post #49
toomuchtodo wrote: post #32

Earlier quoted context omitted.

Electrified high speed rail solves this, with flying reserved for transoceanic needs. Private jets should not exist outside of scientific, medical, or other non luxury/personal use cases. Travel and tourism will always be with us, and should be imho. Carbon taxes, laws, whatever is needed to accomplish it.

> Electrified high speed rail solves this Curious -- what speed are you assuming for such a high speed rail?

The last high speed rail I was on was Fuxing Hao series in China, ~200mph. If we can go faster, go faster. Shanghai Maglev can do ~260mph. Japan’s Shinkansen tops out at ~199mph, a bit higher than the TGV in France (~186mph during commercial operations, but has achieved speed records as high as ~360mph).

Within the scope of land travel, it’s clear it can be built. If it isn’t built, of course, that’s a choice. But it’s a lie to say it cannot be done.

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

#52

Post by pfdietz »

You want a fuel that's chemically identical to current jet fuel, not one burdened with extra oxygen. Yes, this would require more energy, but it would be used more effectively in jets.

A drop-in compatible jet fuel can be made by hydrodeoxygenation of biomass, using Virent's process. The waste cellulose in current US waste streams would be more than enough to displace all current US jet fuel consumption. An extra source of hydrogen would be needed to do this, but hydrogen can be made renewably (and, indeed, that's a good way to provide dispatchable demand to help deal with renewable intermittency, and will have to be done anyway to displace the use of natural gas to make hydrogen.)

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

#53

Post by pudgywalsh »

Saline9515 wrote: post #33
317070 wrote: 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…

> 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 India are the biggest domestic aircraft markets in the world. The manufacturers literally cannot keep up with the demand. If trains were more effective they would have built them already. If California has taught us anything it's that implementation of high speed rail is a joke.

I am appalled at the level of delusion and craziness in these responses, it would take a year to respond to them all.

Air travel is not going anywhere and we are not setting society back 100 years on account of dubious climate histrionics.

Want to save the environment?

Ditch smartphones (future e-waste) and all their useless apps (and resource-sucking infra) we could all live without tomorrow.

Turns out we were as effective in moving goods and services and leisure travel in 2008 as we are today.

We just couldn't post to social media about how uncomfortable the airplane seat was and how the onboard Wi-Fi sucked.

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

#56

Post by [deleted] »

pudgywalsh wrote: post #53
Saline9515 wrote: post #33

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…

[deleted]

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

#57

Post by europoorean »

clickety_clack wrote: post #6

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.

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

#58

Post by Animats »

willtemperley wrote: post #41
mdp2021 wrote: post #9

Earlier quoted context omitted.

They already grow, they are already harvested, and this process uses discarded parts of the harvest. It is putting in use what we already had but had no use for. Edit: the article speaks about possibilities that open. It also clearly notices that the a number of problems are unsolved. The infographic is direct: https://studyfinds.com/wp-content/uploads/2026/08/Coconut-Bi... Note that if some product available in limi…

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 the plant. Not enough to put them into the gas business, though.

Amusingly, corn to ethanol plants in the US do not generally self-power. They consume natural gas to produce ethanol.[2] Net energy gain is maybe 1.3. Only subsidies keep this going. About 40% of US corn production goes into this boondoggle.

Sugar cane, though - that's a win for biomass.

[1] https://www.theguardian.com/world/article/2024/may/10/png-co...

[2] https://en.wikipedia.org/wiki/Ethanol_fuel_energy_balance

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

#59

Post by fc417fc802 »

dylan604 wrote: post #11
mdp2021 wrote: post #9

Earlier quoted context omitted.

They already grow, they are already harvested, and this process uses discarded parts of the harvest. It is putting in use what we already had but had no use for. Edit: the article speaks about possibilities that open. It also clearly notices that the a number of problems are unsolved. The infographic is direct: https://studyfinds.com/wp-content/uploads/2026/08/Coconut-Bi... Note that if some product available in limi…

To what scale though? Doubtful it's going to be enough for a replacement. Just as GP stated, the corn grown for ethanol is nothing more than an additive and it is quite easy to find fuel without it. It's a boondoggle and not any where close to being a fossil fuel replacement

Isn't that simply a matter of cost? It's pretty difficult to complete with pulling an energy dense material out of the ground.

If we were to globally tax oil extraction proportional to the actual cost of equivalent carbon capture I imagine biofuels would begin to look quite reasonable.

That said it seems to me that tying the energy and food supply together economically in such a direct manner is likely to have some deleterious effects on poor countries.

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

#60

Post by openasocket »

steve1977 wrote: post #30
317070 wrote: 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…

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).

I think that's a bad frame of mind in general. One of the primary ways industry tries to prevent regulation is by putting the burden on the individual. People think the only way we can have a healthy environment is by sacrificing things for the average person. And one of the worst things environmentalists can do is play along with that. In the US there's a push to ban plastic straws, which is annoying to the average consumer, while basically every item you can purchase comes wrapped in tons of plastic packaging. Industry LOVES things like this because it does little to actually reduce plastic consumption, and pits the average person against the environmental movement.

As another example, the amount of greenhouse gas emissions from airplanes is several times less than the amount of methane that leaks out of natural gas pipelines every year (here I'm weighting emissions by their global warming impact). The overwhelming majority of those leaks can be prevented with minimal effort, but industry hasn't been incentivized to do so. Maybe before we start banning tourism, we have some inspectors checking pipelines for pinhole leaks?

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