Reply To: Fusion Oil

[Pete Keech]

This post has meandered through some interesting topics, but it has drifted from the original title, fusion oils… I hope this goes to refocussing the discussion…

If FF is viable, liquid fuels will be all produced using electricity, and oil will be over within 5-10 years, and here is why. Even with existing technology, we simply make loads of methanol (wood alcohol for non-chemists). We can crudely use some #’s to see why this approach is possible:

Hydrogen can already be generated (inefficiently) using electricity and (salty) water. I say inefficiently in that you lose up to 1/2 the energy you get back out, even on the best catalysts, but electricity is essentially free with FF, so efficiency doesn’t matter as much as with other fuels. Still, assuming existing efficiency, you find citings that say H2 is 58 kwH electrical power per kg:

H2 production
http://findarticles.com/p/articles/mi_m0JZS/is_17_23/ai_n25010891/

Chemical production is even better, using the sulphuric acid cycle, but look that up on your own if you don’t like my numbers…

Remembering that 1 kg of H2 is a lot of H2 (it’s so light), we can switch to moles & we have:
500 mol H2 using 58 kWh

Carbon dioxide can be captured from the atmosphere directly using electricity. That’s how they make dry ice & store it in gas cylinders. That’s essentially free with FF. There’s even a group that claims they can do it at a cost of 100 kWh/tonne, or about 0.1 kWh per kg with their numbers. We can assume crappy efficiency, so that even at 1 kWh/kg, (since CO2 is 22 g/mol we get 45 mol/kg). To scale up to 250 moles, (since we need 2 H2 per CO2 to make this work, we need) we need 6 kg CO2, which puts our energy budget up to 6 kWh on this process, and a total of 64 kWh to make suitable amounts of H2 and CO2

CO2 sequestering from the air
http://www.ucalgary.ca/~keith/AirCapture.html
http://www.futurepundit.com/archives/005592.html

Hydrogen reacts with carbon dioxide over many catalysts to produce methanol. Assuming efficiency of 50% (extremely low for a chemist), and other losses, lets assume our 64 kWH input energy is actually closer to 130 kWh (i.e. total efficiency of chemical process is only 50%). Just google co2 h2 methanol to see.

http://www3.interscience.wiley.com/journal/75501063/abstract

For cars, methanol burns with minor injector / carb adjustments, at 70% gas efficiency, meaning we can scale our 130 kWh up by another 30% to be 180 kWh. You can easily convert methanol to dimethyl ether and run it directly in diesel engines. We can assume only this fuel has 70% the energy of diesel and say 180 kWh electrical energy is needed. Existing refineries have all the necessary abilities for these chemical step & could probably drive up the efficiency above 90% for these chemical conversions. The ether formation is especially easy already.

For $2, you can generate the required 200 kWh of electricity, assuming .01 $/kWh using FF (and yes I know higher is possible using Lerner’s calcs, but being pessimistic about FF). That means $2 gas or diesel per gallon. End of story, since those days are already behind us. Assume any gains in efficiency, or decreases in electricity cost, and you can make hydrogen with any (dirt cheap) catalyst, like iron, instead of palladium or platinum.

Don’t like methanol? Ethanol (diethyl ether) is possible too.
http://www.ncbi.nlm.nih.gov/pubmed/15604806
That one is a bit further away, but it would come on line very quickly in the age of cheap electricity.

You can eventally make any number of alcohol hydrocarbons, or even hydrocarbons themselves (i.e. put H2 and CO2 back together to make CH4 and H2O at high temp). It’s actually quite easy to do this, as it is just high temperature equilibrium chemistry – keep adding CO2 and H2 and bleeding off the CH4.) Of course, we could just burn the hydrogen in many applications (heating, etc).

Give the chemists the cheap (free) electricity, and liquid fuels will come very very quickly.

On a related note, you can also make loads of carbon (i.e. coal) using nickel catalysts to put that shite back in the ground (agricultural lands are quite carbon hungry nowadays – see biochar discussions).

Consumer reports on fuels:
http://avt.inel.gov/pdf/fsev/costs.pdf