> This is a similar reaction to photosynthesis in plants, which produces glucose instead of rocket fuel.
This is silly, but also begs the sillier question why we aren't bioengineering plants to produce rocket fuel
This is silly, but also begs the sillier question why we aren't bioengineering plants to produce rocket fuel
Plants are self-assembling albeit inefficient photosynthesises.
On earth, where they can harvest their carbon in situ, that inefficiency outweighed by us not having to make them. Their main components by wet and dry mass, carbon and oxygen, are dissolved in atmosphere. In space, on the other hand, the major cost is lifting. (Even earth, farming quickly becomes uneconomical when just water costs balloon.)
In space you’re moving all the mass the plant is built out of at exorbitant cost. At that point, you might as well just assemble the machinery on the ground and get the efficiency boost.
I can only see an exception arising if lifting costs start scaling with volume more than mass, i.e. post chemical rocketry, at which point sending up compacted carbon and water and letting plants assemble themselves in space makes more sense than sending up panels and tiny labs. (That or you’re going somewhere with accessible carbon and/or oxygen.)
I don't know what the actual claim that is being made here is; This seems to redirect ultimately to a lay press release from a state space agency rather than to a scientific paper. There do seem to be a number of competing articles on electrochemical synthesis of ethylene from CO2.
https://www.carboncapturejournal.com/news/artificial-photsyn...
https://www.nature.com/articles/s41467-024-50522-7
https://lanzatech.com/lanzatech-produces-ethylene-from-co2-c...
https://techport.nasa.gov/projects/93860
https://news.umich.edu/in-step-toward-solar-fuels-durable-ar...
Alternatively, you can break it down into ethanol, which has been used as liquid rocket fuel since at least the first half of the '40s.
This classic book tells the story of liquid rocket fuel development
https://library.sciencemadness.org/library/books/ignition.pd...
You'd think that you could mix any of a wide range of fuels with a wide range of oxidizers and get a good rocket fuel but it does not really work that way, most combinations are pretty awful, including the ethanol + O2 used in the V2. There was a time when there was interest in "storable" liquid propellants but once solid propellants reached this level of maturity
https://en.wikipedia.org/wiki/LGM-30_Minuteman
those were obsolete.
It is hard to beat H2+oxygen or hydrocarbons+oxygen if you pick the right hydrocarbons (rocket kerosene isn't quite the kerosene you use in a lamp)
I'm not sure if ethylene is really that good of a rocket fuel. In the context of a space economy I see it as a "reactive carbon" substance which is easy to make other things out of, say,
https://en.wikipedia.org/wiki/Polyethylene
in the sense that glucose is reactive carbon you can build structural carbohydrates and all sorts of biological molecules out of. There is talk about SpaceX establishing a methane economy on Mars, methane is definitely an easy to synthesize rocket fuel but it not very reactive and not on the path to making other things you might want.
Sort of early 'RoundUp' with high contents of Sodium chlorate combined with powdered sugar. Very dangerous! But fun :-)
Even more fun, but potentially fatal very fast would be Potassium chlorate.
But I've been cautious, and limited myself to selfmade blackpowder mostly, during the times one 'did that' as young boys with toys.
Still have all my fingers, no burn scars, full eyesight & hearing, though. Phew! :-)
Btw, when I did this the internet didn't exist, 1977 to 1980, I think. It was in schoolbooks for chemistry, not chlorate stuff, but blackpowder at least. I also went into university libraries for more advanced stuff, after understanding teachers gave hints, and warnings, about not doing anything which one doesn't really understand. Not limited to explosives. Toxicity, fumes, pH, and so on.
We've been really dumbed down. No more interesting experimental kits ( https://en.wikipedia.org/wiki/Chemistry_set ) . No more availability of the ingredients. I could walk into a drug store and get that stuff for chump change, there. Not needing to produce finest charcoal myself. Or sulfur. Potassium nitrate. Flashbulbs and a 9V-block and some wires for electrical ignition!1!!
Bang! Whee!
edit: Thinking about it I can't shake the feeling that it did not make us safer. Though that may depend on the country.
Anyway, one does hear and read about much more loud booms caused by reckless use of smuggled illegal fireworks year round. Be it just for fun, ripping up trashcans, recycling containers, shopping windows, ATMs...
Or the really 'good stuff' (military) smuggled in from afar.
Or, well... just guns?
For now and the near future there are no ways of doing that part otherwise than by using living plants or fungi, possibly with genome modifications.
The part with capturing solar light and splitting water and reducing carbon dioxide to a very simple carbon compound can be done with artificial means much more efficiently than in plants, so there is little doubt that this will become commonly used in the near future.
Ethylene or methane are good for fuel or for making plastic, but when a slightly more complex organic substance were made, e.g. glycine or glycerol, that could be used to feed a culture of fungi, which could be used to make human food, especially if genetically-modified to make higher quality proteins.
Cyanobacteria that can exist in the vacuum of space AND produce oxygen... just not fast enough to be useful, but one day, a big hairy space ship will rule the universe!
See: https://www.reddit.com/r/space/comments/1acqxml/lichen_survi...
I'm sure the economics don't work out for it: solar panels are already cheap, the land could grow other crops, etc. But photosynthesis being lower-yield than photovoltaic generation isn't enough to rule it out. Perhaps as science fiction, on a future mission to an Earthlike planet that doesn't have the right resources to produce semiconductors at scale.
growing the fuel plant is probably easy.
How do you get it OUT of the plant?
Solar panels just sit there (they do need cleaning i admit) and produce electricity that we can manipulate very cheaply already.
What machine collects diesel from plants? Can you safely dispose of the plant matter?
Methanol is also known as "wood alcohol", and can be made at ~40% yield by cooking down wood ("destructive distillation") in a specific fashion, or made from too-cheap-to-meter natural gas if you've got it. Anything you can do with natural gas can also be done with anaerobically fermented methane. You can also use ethanol (fermented from any carbohydrate crops) instead of methanol, creating a biodiesel with slightly different but still usable properties.
...
Sunflower, rapeseed, and soybean oil have very well-established agricultural workflows which require very little labor input.
Palm oil is substantially higher yield, but more labor intensive and is associated with tropical rainforest destruction.
...
You don't necessarily even need to react your vegetable oil. The original Diesel Cycle demonstration engines ran on straight peanut oil, and there are some truck engines out there (like the 12 valve Cummins) that will happily run on filtered waste fryer oil all day long. It's just a matter of tuning, viscosity, compression ratios, seal materials, and the like, being slightly different from petrochemical diesel fuel. Reacting vegetable oils into fatty acid esters ("biodiesel") does attain some modest engine benefits, but mostly it's to match compatibility with petrochemical diesel grades so that you don't, eg, need to replace your fuel lines & pumps with different diameter fuel lines & pumps.
False dichotomy. There are places where food does not grow at all and can be used to grow fuel crops. Say, the ocean.
https://en.wikipedia.org/wiki/Wood_gas
It's wildly inefficient though and not worth the trouble compared to solar panels and batteries.
Making and then using „diesel trees” would definitely require special equipment and manufacturing pipelines that might be the same cost or more than those for solar panels.
Measured how? If nothing else, they seem to be good at carbon capture. And I don't see how you it could account for engineered for plants engineered to store more of their energy as oil.
"Ecologically informed solar enables a sustainable energy transition in US croplands"
https://www.pnas.org/doi/full/10.1073/pnas.2501605122
As a rough estimate, you'd lose 2/3 of that energy if the electricity had to be turned into liquid fuels. That would still mean 10 times greater usable energy produced per acre.
Plants genetically engineered for fuel production might be somewhat more efficient in the future, but future solar farms are also probably going to be more efficient.
I would have expected there to be multiple processes with similar or aligned timings, or some built in limiting mechanism or something... it's not like giving humans higher calorie food makes them become adults faster.
I'm sorry, were they measuring the carbon footprint of growing algae by what it takes to grow it inside with artificial light?
I don't think any food crisis scenario in the US involves a road bump that spans a single year and doesn't disrupt existing crops.
The only real issue with Ethanol IMO is that corn Ethanol is preventing progress in advanced synthesis made out of, ex: switchgrass cellulose. There are better sources of ethanol if we invest into them.
It costs more money and has a higher carbon footprint than simply using gasoline.
The carbon footprint thing doesn't past review of the overall literature. There's one outspoken guy who has to bend over backwards and publishes media articles rather than keeping things academic who tries to make the public believe what you say, but I'm not convinced he's arguing in any serious manner.
Stupidest possible thing to do with food. Especially since in some operations you put in more diesel than take ethanol out.
edit: Looked it up - Rice has the highest number of calories per square metre of farmland, just that it requires marshy/swamp land to grow.
It doesn't make economic and enviromental sense in most parts of the world (especially corn). In some places they are net-positive on carbon emissions compared to oil-derived gasoline. Tilling the fields, growing, harvesting, processing and transporting often emits more CO2 than the equivalent gasoline produced. Especially the initial tilling of the land to convert it to farmland releases A LOT of CO2 into the atmosphere (this is a one-time thing though).
In the US all (ground vehicle) gasoline sold needs to have 10% ethanol (corn-based), in Brazil it is 20% (sugar cane based). In Brazil almost all cars support 100% ethanol fuel and it is quite common to fuel with ethanol only.
https://en.wikipedia.org/wiki/Ethanol_fuel_in_Brazil
The whole bio-fuel industry is a very complex mix of economics (often requires subsidies to make sense), geopolitical (less imported oil), environmental concerns (mass scale farming soil degradation and CO2 emissions derived from it) and logistical (completely different transportation and refining process).
Fun fact ethanol freezes at a fairly high temperature and mixes with water which makes it not ideal for cold climates and boats. It is quite common for unaware boat owners to f-up their engines by buying car-grade fuel-station gasoline in Brazil.
30% in 2025 for cars (from 27%), 15% biodiesel in diesel for trucks (from 14%).
Source: https://www.em.com.br/politica/2025/06/7183470-governo-aumen...
> The whole bio-fuel industry is a very complex mix of economics (often requires subsidies to make sense), geopolitical (less imported oil), environmental concerns (mass scale farming soil degradation and CO2 emissions derived from it) and logistical (completely different transportation and refining process).
Don't forget lobyying by the relevant sectors!
Still people will want to keep classic cars running in the future and there will be some market, enthusiasts will be willing to pay upwards of $8/gallon. Methanol-to-gasoline fuel is very high octane, around 96, which should keep old engines happy.
The most significant market, I think, for e-fuels are large vehicles such as construction trucks and farm tractors. California has absolutely terrible air quality not just in cities but in ag areas and it would be ideal to synthesize
https://en.wikipedia.org/wiki/Dimethyl_ether
which burns without any soot because it has no C-C bonds.
Mythbusters: https://youtu.be/QEX1YFXYTdI
TopGear: https://youtu.be/GOFbsaNeZps
I suggest travelling around the world a bit and visiting ie Borneo how entire rainforest ecosystem is being reduced to nothing just due to palm oil plantations, mostly for biofuel and cheap&bad for health food additive.
Similar sight across many places out there. What you wrote ain't valid for a single one.
Both have since been improved upon somewhat.
No generators to connect to a power grid, nothing to use the power for, but they could still transport electricity in the time before writing.
If we need infrastructure to make use of energy we can ‘magic’ it up.
https://www.ers.usda.gov/publications/pub-details?pubid=1057...
Our digestive systems heat and oxidize hydrocarbons to generate kinetic energy? You sure about that?
Of glucose, not a hydrocarbon, but there are plenty of organisms that use hydrocarbons directly.
We don't because we use glucose as our easily transportable fuel, which we evolved because plants happened to produce glucose when we evolved. If there were plants producing some hydrocarbon in fruits we'd have evolved mitochondria to use that instead.
In a more serious response almost all questions like yours can boil down to economics. You can be certain if there is a way make something at a profit someone will jump in and make it happen. If there is no money in it you can expect that even if it is more environmentally friendly it may be part of research but not going to be implemented unless it becomes profitable.
Very intriguing is the Primeval Code[0] in which plants and other life exposed to electrostatic fields changed significantly down to the genome.
Would be very interesting which other artificial settings and compositions affect life in which ways.
(I say this in the friendly spirit of a long-defeated fellow pedant who has hit people with your exact comment for decades)
as a non-native speaker that confused me quite a bit in the beginning.