Audi unveils a synthetic E-diesel ,made from water and CO2

[ghi]

 Interesting way to  save the world from warming   

   "Making e-diesel requires several steps, which are powered by renewable energy sources such as wind and solar. High-temperature electrolysis splits water, heated to form steam, into hydrogen and oxygen. The oxygen is released into the atmosphere while the hydrogen is fed into a reactor, where it reacts with CO2 to form a liquid long-form hydrocarbon known as “blue crude.” Audi says the  efficiency of the overall process is “very high”—about 70 percent.

“The engine runs quieter and fewer pollutants are created,” says sunfire Chief Technology Officer Christian von Olshausen. He says the demonstration facility, which opened in November, can produce up to 160 liters (42 gallons) per day, but a bigger plant could follow."

http://news.nationalgeographic.com/energy/2015/04/150428-audi-ediesel-made-from-water-air/

[Masherbrum]

No thanks.   They cannot even design an effective water pump for a 1.8L turbocharged engine.   

[pembquist]

It seems to me the question is how much energy does it take to extract CO2 from the air and how much energy does it take to complete the reactions to produce the fuel vs how much energy it takes to make/charge a battery. I assume that a chief attraction of this system is that the density of power per Kg of fuel surpasses by orders of magnitude the equivalent performing battery or fuel cell systems. This may make sense for weight critical applications such as aviation but shouldn't the  overall efficiency be the guiding light in more prosaic terrestrial applications such as motorcars or truck transport? Isn't the low efficiency heat engine (see Carnot) a technological dead end?

Have you ever had a good red Ale? I've had morenacouple.

[zack1234]

Do you use this in your Il2?

[rpm]

Will it work in a fiberglass engine?

[JOACH1M]

Looks good on paper, doubt it will work as good as it sounds...


On another note, Porsche is working on an variable compression engine! Now that is cool!   

[craz07]

Anything going in this direction is a good thing hopefully it will be a great thing...

[PR3D4TOR]

It's an improved Fischer–Tropsch process. The same process Germany used to make avgas from coal during WWII. Apparently it is around 70% energy efficient and only need water (for the hydrogen) and air (for the carbon).

[oboe]

It's an improved Fischer–Tropsch process. The same process Germany used to make avgas from coal during WWII. Apparently it is around 70% energy efficient and only need water (for the hydrogen) and air (for the carbon).

That seems dubious to me - they don't say where they are getting the CO2, but you're saying they extract from the air?   The concentration of CO2 in air is still pretty low, I mean, air is what, 78% Nitrogen, and they don't even use it as a source for Nitrogen when making fertilizer.   I would think there have got to be some materials high in carbon and some chemical reaction could be employed on that material that would liberate CO2 as a byproduct.

You mentioned making avgas from coal - that's probably where the carbon came from, not air.

[MrRiplEy[H]]

That seems dubious to me - they don't say where they are getting the CO2, but you're saying they extract from the air?   The concentration of CO2 in air is still pretty low, I mean, air is what, 78% Nitrogen, and they don't even use it as a source for Nitrogen when making fertilizer.   I would think there have got to be some materials high in carbon and some chemical reaction could be employed on that material that would liberate CO2 as a byproduct.

You mentioned making avgas from coal - that's probably where the carbon came from, not air.

For some time there have been efforts to dump CO2 from industrial processes into ground storages. There are probably a lot of sources of 'waste' CO2 that could be used. But that wouldn't be so hippy and 'environmental' if yet another green process would actually use byproducts of oil lol.

[PR3D4TOR]

That seems dubious to me - they don't say where they are getting the CO2, but you're saying they extract from the air?   The concentration of CO2 in air is still pretty low, I mean, air is what, 78% Nitrogen, and they don't even use it as a source for Nitrogen when making fertilizer.   I would think there have got to be some materials high in carbon and some chemical reaction could be employed on that material that would liberate CO2 as a byproduct.

You mentioned making avgas from coal - that's probably where the carbon came from, not air.

In WWII they used coal. The article the OP linked to says: "Audi has been working on cleaner diesels since 2009, and the only raw materials needed for its newest synthetic are water and carbon dioxide. Its pilot plant in Dresden, operated by the German clean technology company sunfire, uses CO2 supplied by a biogas facility. Additional CO2 for e-diesel is captured from ambient air via technology from Audi’s Zurich-based partner Climeworks."

[oboe]

Thanks Predator for clearing that up.   I don't know how I missed the link for the article!

Still seems crazy inefficient to me - CO2 is only .04% of air by volume (not that I want it any higher!).

[PR3D4TOR]

I'm guessing the "green" aspect takes priority. Making "carbon neutral" diesel.

[Dragon Tamer]

Thanks Predator for clearing that up.   I don't know how I missed the link for the article!

Still seems crazy inefficient to me - CO2 is only .04% of air by volume (not that I want it any higher!).

They have an army of midgets that hyperventilate into plastic bags, that's where the CO₂ comes from... 

[DaveBB]

That seems dubious to me - they don't say where they are getting the CO2, but you're saying they extract from the air?   The concentration of CO2 in air is still pretty low, I mean, air is what, 78% Nitrogen, and they don't even use it as a source for Nitrogen when making fertilizer.   I would think there have got to be some materials high in carbon and some chemical reaction could be employed on that material that would liberate CO2 as a byproduct.

You mentioned making avgas from coal - that's probably where the carbon came from, not air.

Have you ever heard of a gigantic chemical company called "Air Products"?  All they do is freeze gasses out of the air.  Molecular nitrogen is in very high supply in the chemical industry to prevent corrosion and control chemical reactions.  100% O2 is in demand for wastewater treatment plants for secondary (biological) treatment.