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Making Jet Fuel From Seawater While at Sea

nrl.navy.mil

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Re: Making Jet Fuel From Seawater While at Sea

#21

Post by 001sky »

ChuckMcM wrote: post #10
jws wrote: post #3

Extract CO2 and H2 from seawater, react to form hydrocarbons of varying lengths, then refine. Presumably all powered by the nuclear reactors. initial studies predict that jet fuel from seawater would cost in the range of $3 to $6 per gallon to produce

That is exactly why its such a big deal. Current jet fuel costs over $8/gal delivered. It costs so much because even if it comes out of the refinery at San Diego at $2/gal it has to be loaded into an oiler [1] and then driven out to sea where the carrier task group is. If you're on a nuclear powered aircraft carrier you have plenty of electricity so this is a pretty huge win. Of course an alternative way to make this…

An alternative way to make this feasible for the fleet would be to build a nuclear powered oiler

--Interesting Idea, depending on the incremental weight, complexity and volatility of the Carrier system.

Re: Making Jet Fuel From Seawater While at Sea

#22

Post by comicjk »

sien wrote: post #16

This is a good reason why Tesla cars are folly. This is why electric vehicles won't work. I'll copy in most of a comment I made a few days back. Let's say tomorrow some grad student gets fusion going at a very low price. The best way to use this to power cars would be to use it to create a fuel with a high energy density. If you had 'free energy' you'd extract C02 from the atmosphere and turn it into a hydrocarbon. F…

Lithium-air batteries (an immature technology, certainly) have an energy per gram 3.5 times less than gasoline's. But electric motors are about 3.5 times more efficient than internal combustion engines. And the technology to produce synthetic fuels from CO2 is pretty much as far from mass scale as lithium-air batteries.

I agree that we will need carbon-based fuels for jet engines, but as for cars, the physics and economics are by no means as favorable as you represent.

Re: Making Jet Fuel From Seawater While at Sea

#23

Post by danmaz74 »

jnw2 wrote: post #15
ChuckMcM wrote: post #10

Earlier quoted context omitted.

That is exactly why its such a big deal. Current jet fuel costs over $8/gal delivered. It costs so much because even if it comes out of the refinery at San Diego at $2/gal it has to be loaded into an oiler [1] and then driven out to sea where the carrier task group is. If you're on a nuclear powered aircraft carrier you have plenty of electricity so this is a pretty huge win. Of course an alternative way to make this…

http://en.wikipedia.org/wiki/USS_Gerald_R._Ford_(CVN-78) notes that ``Unfortunately the power limitations for the Nimitz class make the installation of the recently developed [Electromagnetic Aircraft Launch System] impossible.'', which seems to indicate that existing nuclear powered aircraft carriers don't always have large amounts of electricity to spare. However, more electricity will be available on future aircra…

But the launch system has to work reliably at any moment, especially when the ship is in full operation at a time of crisis. On the other hand, this process could work at off-peak times, of which I think there is plenty on a carrier too.

Re: Making Jet Fuel From Seawater While at Sea

#24

Post by ChuckMcM »

jnw2 wrote: post #15
ChuckMcM wrote: post #10

Earlier quoted context omitted.

That is exactly why its such a big deal. Current jet fuel costs over $8/gal delivered. It costs so much because even if it comes out of the refinery at San Diego at $2/gal it has to be loaded into an oiler [1] and then driven out to sea where the carrier task group is. If you're on a nuclear powered aircraft carrier you have plenty of electricity so this is a pretty huge win. Of course an alternative way to make this…

http://en.wikipedia.org/wiki/USS_Gerald_R._Ford_(CVN-78) notes that ``Unfortunately the power limitations for the Nimitz class make the installation of the recently developed [Electromagnetic Aircraft Launch System] impossible.'', which seems to indicate that existing nuclear powered aircraft carriers don't always have large amounts of electricity to spare. However, more electricity will be available on future aircra…

If you look at the power requirements for the EMALs system you will see why a Nimitz class carrier can't power it. Not only is it a crapload of power, its needed all at once. The JP4 from Seawater project can run at much lower powers and for long periods of time.

Re: Making Jet Fuel From Seawater While at Sea

#25

Post by ChuckMcM »

Sukotto wrote: post #12
jws wrote: post #3

Extract CO2 and H2 from seawater, react to form hydrocarbons of varying lengths, then refine. Presumably all powered by the nuclear reactors. initial studies predict that jet fuel from seawater would cost in the range of $3 to $6 per gallon to produce

That's a great deal. Jet Fuel (Kerosene) closed at $3.135/gallon today[1]. And that doesn't include the cost of transporting it from the Gulf Coast to where your Navy needs it. [1] Sep 28, 2012: http://www.eia.gov/dnav/pet/pet_pri_spt_s1_d.htm

To be fair you have to subtract off Federal taxes which the government doesn't pay for the fuel it buys which brings it down closer to $2/gal.

Re: Making Jet Fuel From Seawater While at Sea

#26

Post by FrojoS »

Once again, military research might lead the way. Note, if they invest into this, it's _not_ because of reduced price, increased efficiency or reduced greenhouse effects, but because of an _strategic_ advantage against "the enemy".

Personally, I read about similar methods, for synthesizing carbon based fuels, many times before. Most of them were private founded but rather small scale. I can't judge if there was a significant science or engineering breakthrough. So, I suspect the only thing that might have changed, is that a clever guy convinced the military this would be a huge strategic advantage.

The ironic thing is, the US could instead focus on producing all their fuel at home to end the dependency on oil from the middle east. Then, they would have an even bigger strategic advantage and wouldn't need as much military investment. Anyway, we might end up with synthetic carbon based fuel with all its advantages - and probably the military can keep their carriers.

Re: Making Jet Fuel From Seawater While at Sea

#27

Post by sien »

ta12121 wrote: post #20
sien wrote: post #16

This is a good reason why Tesla cars are folly. This is why electric vehicles won't work. I'll copy in most of a comment I made a few days back. Let's say tomorrow some grad student gets fusion going at a very low price. The best way to use this to power cars would be to use it to create a fuel with a high energy density. If you had 'free energy' you'd extract C02 from the atmosphere and turn it into a hydrocarbon. F…

No. Electrolysing water to make H2 and extracting CO2 from the environment, and then synthesizing hydrocarbons from them, is extremely energy inefficient. Sure, theoretically, it can be done, and maybe one day it could even be done efficiently. But Tesla is making battery-electric cars that work today . The military does not care about efficiency because they have nuclear reactors on their ships and their goal is to…

If they can hit $3 / gallon why does it matter?

Tesla's cars are wildly price inefficient because they cost $100K. For 10K you can get a decent car that has 4 times the range. http://en.wikipedia.org/wiki/Tesla_Roadster

How many gallons of fuel can you get for 90K?

They are nice toys for rich people. Perhaps there is a market for that. Good luck to them.

But for mass transit unless you can get the price of the batteries to plummet it just does not work.

Re: Making Jet Fuel From Seawater While at Sea

#28

Post by rhizome »

sien wrote: post #27
ta12121 wrote: post #20

Earlier quoted context omitted.

No. Electrolysing water to make H2 and extracting CO2 from the environment, and then synthesizing hydrocarbons from them, is extremely energy inefficient. Sure, theoretically, it can be done, and maybe one day it could even be done efficiently. But Tesla is making battery-electric cars that work today . The military does not care about efficiency because they have nuclear reactors on their ships and their goal is to…

If they can hit $3 / gallon why does it matter? Tesla's cars are wildly price inefficient because they cost $100K. For 10K you can get a decent car that has 4 times the range. http://en.wikipedia.org/wiki/Tesla_Roadster How many gallons of fuel can you get for 90K? They are nice toys for rich people. Perhaps there is a market for that. Good luck to them. But for mass transit unless you can get the price of the batter…

In non-currency terms, this sounds a lot like Unix-Windows arguments 15 years ago. If you can bundle Windows, why does it matter what computer you get? For 1/10 the price you can get a great Windows PC with 10 times more software. Tesla Roadster being like an SGI or Solaris box, Linux/FreeBSD is just for snobby nerds who like to tinker. Unless you can make it easier to use it just does not work.

Re: Making Jet Fuel From Seawater While at Sea

#29

Post by lumberjack »

sien wrote: post #16

This is a good reason why Tesla cars are folly. This is why electric vehicles won't work. I'll copy in most of a comment I made a few days back. Let's say tomorrow some grad student gets fusion going at a very low price. The best way to use this to power cars would be to use it to create a fuel with a high energy density. If you had 'free energy' you'd extract C02 from the atmosphere and turn it into a hydrocarbon. F…

Your argument is only balanced on that one premise of Fusion or free energy, both of which are still vaporware and will be for decades if not centuries to come. Have you considered that maybe electric cars will fill the gap between now and then if ever? And you consider free energy a possibility but advancement in battery technology too far fetched. I don't agree at all.

Re: Making Jet Fuel From Seawater While at Sea

#30

Post by ommunist »

ta12121 wrote: post #20
sien wrote: post #16

This is a good reason why Tesla cars are folly. This is why electric vehicles won't work. I'll copy in most of a comment I made a few days back. Let's say tomorrow some grad student gets fusion going at a very low price. The best way to use this to power cars would be to use it to create a fuel with a high energy density. If you had 'free energy' you'd extract C02 from the atmosphere and turn it into a hydrocarbon. F…

No. Electrolysing water to make H2 and extracting CO2 from the environment, and then synthesizing hydrocarbons from them, is extremely energy inefficient. Sure, theoretically, it can be done, and maybe one day it could even be done efficiently. But Tesla is making battery-electric cars that work today . The military does not care about efficiency because they have nuclear reactors on their ships and their goal is to…

I think you are right. Also that last mile Boosted Desk surfing transport is quite a thing. Batteries are forever.
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