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A comment on Making Jet Fuel From Seawater While at Sea. Parent comment

Re:Making Jet Fuel From Seawater While at Sea by ta12121 on Saturday September 29, 2012 @12:39PM (#4590063)
The amount of energy needed to refine crude oil is much less than the energy it takes to synthesize it. Think about it: people refine the crude, transport it, and use the end product in an energy net positive manner. To synthesize hydrocarbon fuel, you need to put in at least the amount of energy you're going to store, and with current technology probably 2 times as much at least due to inefficiencies. Then you need to still account for building and running the nuclear reactor. Try to imagine the systems as a whole, the number of steps and losses at each step. The scheme does not make sense.

1) uranium -> nuclear power -> expensive synthesis -> local transport -> fuel

2) uranium -> nuclear power -> transmission lines -> charging batteries

3) crude oil -> refinement -> transport -> fuel

EDIT: Found a reference from another comment: http://en.wikipedia.org/wiki/Fischer%E2%80%93Tropsch_process... It says that the input energy is 2-4 times the stored energy for synthesized hydrocarbon fuel.

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Re:Making Jet Fuel From Seawater While at Sea by danielharan on Saturday September 29, 2012 @11:26PM (#4591853)
Asking me to imagine a system as a whole doesn't prove your argument.

Instead of the energy system, consider the cost of military supply lines. There's more than the financial cost of delivery; long supply lines are vulnerable to attack and disruption. You don't need to imagine an example: consider IEDs in Afghanistan. Many of those were trucks delivering food and fuel to bases. Efficiency (i.e. insulating tents so less fuel is needed for A/C) results in less deliveries and less deaths.

The same principle applies at sea. Oil ships are a vulnerability and another thing to plan, as well as a major cost that can be more important than the energy efficiency issues.

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Re:Making Jet Fuel From Seawater While at Sea by ta12121 on Sunday September 30, 2012 @12:03AM (#4591918)
I missed the part where you brought the argument back to the military. Yes, it makes sense for the military, as I acknowledged in my original post. The Parent, however was claiming that electric cars for general use are made moot by this technology, which is certainly not the case.
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