Fuel From Seawater

[K_V_B]

The problem is that the title of this post is wrong. It's not "fuel from sea water". It's "fuel from seawater and lots of electricity"...

Once you get that, you understand it's not useful for yachts. Yachts don't have the electricity to spare.

[knot smart]

i need a beer

[seandepagnier]

Keep in mind the electriciy generated from a nuclear plant is very inefficient, and our reserves of easily obtainable nuclear material are quite depleted as well. Such a terrible waste to use uranium to make steam when it could well be the only ticket we have at reaching the stars.

If they are indeed reaching 92% efficiency at electricity to hydrocarbons, it could be very useful if powered by photovoltaics. What catalysts are required? It's fairly straightforward to produce methane from water and co2, and even ethanol can be done but is more complicated, but all processes I know of are much less efficient and require expensive catalysts.

[IdoraKeeper]

A refinery on a warship? Don't refineries have problems with explosion and fire, even when operated for profit? ( explosion and fire being negative with regard to profit) let's give this technology to Putin! Let the Russian's make nuclear powered vodka.....just sayin.

[kas_1611]

just to add my 2p worth to the debate

I work on an oil rig, actually an ultra deepwater drill ship, that uses 75m3 (cubic meters) of fuel oil a day. At 6.289 barrels to the m3 and 42 US gallons to the barrel that works out as 19,810 US Gallons a day, which is 825 gallons an hour. This for a 200m long ship that goes nowhere, running 6 massive marine engines. Therefore it is not inconceivable that a Navy ship sailing around, even at cruising speed, could use 1000 gallons an hour.

By the way 1000lbs of fuel is roughly 150 US gallons depending on type of fuel used (based on diesel).

[jimbunyard]

From the Naval Research Labs' own feasibility and capital costs study:

"The initial calculations indicate that the production of hydrogen requires a significant amount of energy to synthesize the fuel and that this energy is almost twice the amount of energy that would be stored in the liquid hydrocarbon fuel that has been synthesized."

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And:

"The overall energy balance would be unfavorable with the produced liquid hydrocarbon fuel being a little over half the energy of the entire process needed to produce the fuel.

It should be noted that the actual hydrogen and carbon monoxide/dioxide gas phase reactions are catalytic and highly exothermic, so this would tend to improve overall energy balances. Though the energy balance is unfavorable, electricity can't and never will be able to fuel jet turbines, so this unfavorable energy balance should not be a deciding factor against this proposed energy conversion scheme."

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Also, in reading through the costs study, I noticed that the dollars per gallon figures being batted around seemed to reflect different energy generation costs, from nuclear power to ocean thermal energy conversion to commercially available electricity, so it may be hard, or even impossible, to attach a credibility value to these prices.

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So it appears that while it may be ok for the Navy, maybe not so much for us, at least at current prices.

[Canibul]

stand by for the new seawater fuelification tax.

Does this mean we can FINALLY dump the farce of ethanol?

[IdoraKeeper]

OMG now your advocating a tax on seawater? Better a tax on gumbo.

[Canibul]

Oh no, no.. I am NOT advocating additional taxes, I am EXPECTING additional taxes. Just call it a hunch.

But, but...but....don't we NEED to increase taxes to study ways to support all the academics who study these things throughout their careers without ever finding any solutions? Otherwise, all the climate change fanatics might become journalists instead!! Where they can REALLY do some damage.

[valhalla360]

Electrolysis to create fuel from the resultant hydrogen is nothing new. Formulating it into a liquid fuel that can be burnt by turbines is interesting but doesnt' solve the ultimate issue, you need large amounts of energy to generate the hydrogen.

Nuclear carriers have that source of energy available. Your average cruising sail boat doesn't.

[IdoraKeeper]

So, you are against tax dollars being spent to develop a nuclear powered vodka refinery? Imagine the revenue from an appreciation in the value of seavwater....besides, when you tax something you get less of it, right? This is a solution to rising sea levels.��

[Stumble]

I did some more digging, and it looks like it takes the equivalent electrical power of 2 gallons of avgas to make one gallon. So it's a pretty inefficient way to make fuel for most purposes. Unless you happen to have an underutilized nuclear reactor laying around.