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Turning Carbon Dioxide to Fuel

I suppose this might be the holy grail, but doesn't it make your nose twitch.

I admit that there is a lot of Carbon dioxide in the air.... Wait a minute there is only 0.03% of the air that is CO2. Perhaps I am dense. If you want to start using this in production then you need to be able to pipe in CO2. If you just leave it in say the desert, you will suddenly have a "zone of depression" around the converters. Ideally you would need to have a CO2 generator sitting nearby (say a nice coal fired power plant) which siphons off the CO2 from its stack and directs it to the array (cause you are going to need an array of these things, we are limited by the 19 - 56 W/m^2 of direct power from the sun).

Maybe we should just let the stack pump directly through the array, and have another stack at the other end.

Maybe we stick collection systems on all vehicles (since they are a major component) and force the collection bottles to be returned to the facility which converts it back to fuel... We will ignore the fact that this would require compression equipment and might result in the cars efficiency going down dramatically. Compressors, if I remember correctly aren't exacly the cheapest thing to run. They draw a lot.

Of course we could also just stick pipes up the mouths of Al Gore et al and connect them to the system. That should provide us a ton of energy.

Re: Turning Carbon Dioxide to Fuel

Speak of something and then someone does exactly what you describe.

Re: Re: Turning Carbon Dioxide to Fuel

I must be dense or something:
Why, if you have a nice efficient solar panel, would you use the energy to split CO2 into CO and O2?
About all you can usefully do, surely, is recombine the CO with O2 .... fuel (CO) plus oxygen (O2) gives CO2..
Now surely,
Energy Out = Energy In - Losses...
Unless these guys are splitting the atom or something, and it didn't seem they were, surely each sequential activity will be a net consumer of energy and we will get losses? Or do they claim one or more steps is over 100% efficient?
I mean, just what is the point?
CO2 is free?
solar energy is free?
Well, no. To be useful, you need some gismo to convert the available energy into useful work. Solar panels are not the most cost effective solution to begin with and now we appear to be adding in some expensive catalysts and dropping the efficiency of the energy to work process.
The more intervening steps the lower the efficiency, or should I start saving my pennies to buy one of these things?

Re: Turning Carbon Dioxide to Fuel

There is an alternative secret device, known only to the public. It goes by the name of a green leaf.

Re: Re: Turning Carbon Dioxide to Fuel

Green leaf gives us tall trees which in turn give us firewood.... ****, that bloody miraculous.

Where's the pope.

Re: Re: Re: Turning Carbon Dioxide to Fuel

If such a device were created then we would have to kill all the trees to maximize our energy creation potential.

Would this be another example of the enginasters in action. The inability to draw a box around their machine and wonder where the inputs are going to come from. Or is this just a great way for me to dangle participles.

Re: Re: Re: Re: Turning Carbon Dioxide to Fuel

Here we are, a solution mentioned today on Jerry Pournelle's site;

On the face of it it seems neat. Power station CO2 into algae tanks, add sunlight and get something out which can be processed into diesel.

Re: Re: Re: Re: Re: Turning Carbon Dioxide to Fuel

Interesting and, on the face of it, about the only biodiesel production system with enough gain to be a usefully net producer of energy. When you analyse biodiesel system based on conventional crops most have small or negative (sometimes quite large) negative returns.
No mention of other nutrients needed or processing/transport energy costs between algae and biodiesel tho'.
Of course if its power-station based using such algae produces to replace smoke-stack scrubbers gives you a running start. In that application even going down to a net zero financial return relative to the cost of the replaced scrubbers would be worth it.

Re: Re: Re: Re: Re: Re: Turning Carbon Dioxide to Fuel

Everyone seems to accept that bio-diesel is a great idea.
Of course, the starting point, the "Big Idea" and propaganda hook was the idea of converting all that McDonalds chip fat into fuel.
Once having planted that idea it is an easy step to extend the benign concept such that everyone believes bio-diesel is about as eco friendly as you can get, without actually thinking it through.
Sadly, we utilise a lot of the landscape for food production. This means that if we want to eat and have bio-diesel, we need more landscape and that means fewer Orang Outangs (to name but one cuddly species).
Now here is another big question for the greenies... should bio-diesel be organic?