Isn't it written in stone that you have to put more energy into water than can be extracted from it?

I can see how astronauts could need oxygen from water on the moon, but haven't we always been told it takes more energy to separate the molecules than can be gained from burning them?

In reply to a response from my last question, I referenced something I read a long while back. It was about deep space probes extracting water from Mars or other planets and using it for fuel to go even further (faster I'm assuming).

So sure, astronauts need to breathe, and would be able to recoup some of the lost energy  from the hydrogen, but how would an unmanned space probe benefit from such a loss of energy?


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seandogue7 years ago
well...yes... but who cares?  If you have a source of "free" electrical energy, like a solar panel, a magnetic field probe (see your last question and cyberpageman's response), etc, then what you need is a working material. Water happens to be a logical working material. We can drink it, breathe part of it, use it as a  radiation shield, and use it's recombination as a propellant (mass ejection and conservation of momentum).

I'm not sure I'd be inclined to use what little water exists on Mars as a propellant for human interpalanetary travel, but for small probes it seems a reasonable choice right now. I'd think we would have to venture a bit father out into the solar system before we could start mining water from extraterrestrial objects for use with human space travel.
owendrake (author)  seandogue7 years ago
I really put this question up more for the purpose of getting other peoples feedback on this topic. I mean, to the best of my knowledge you can't fire a rocket on solar energy alone so some type of fuel is necessary for saving precious years of travel time.

Paranoid as anyone's logic may think it is, I can't shake the gut feeling that many viable energy sources have been squashed and hidden from the world for decades. There is just too much money for governments to make by preaching about our "addiction to oil".

Take this guy for example, his discovery was written about in Popular Science in '07 but yet that and YouTube are the only places I've heard anything about it. And that was only after searching for it to show someone else. And I'm the type of person who is always looking for things of such an interesting nature.

-Burning Saltwater-
http://www.youtube.com/watch?v=lemZaEYFjtI&NR=1

Even if this isn't a major breakthrough for our energy problems, it still should have endless possibilities for other applications. This could be modern day Greek Fire. Imagine what a 4000 degree flame could do to a ships hull or a small band of pirates.
Sorry. I didn't mean to sound as though I'm skeptical of your thought process. I'm not. In fact I enjoy your thinking. It beats the hell out of "hey, if I hook an electric motor up to a generator", and it touches on subjects that I am interested in (practical utilization of space)

I'm still a bit skeptical about the burning saltwater thing being a free energy source, even if I saw it burn on TV which proves little more than that he has performed electrolysis using radio waves instead of by conventional conductive means. (local tv too...hmm...)

Have you duplicated his work? I'd like to know the amount of energy that has to go into creating the field he uses to dissociate the water, the specific salt and molarity he uses, etc.
owendrake (author)  seandogue7 years ago
Sorry, I missed your question somehow. According to Popsci this has been tested by legit sources. I think it was still up in the air as to whether or not it could be put to any practical application.

I have not tried to duplicate this but have read from others who have attempted and failed. One guy said he was trying to work from the patent application he found and still failed.
np...it's bidness as usual around here ;-)

Interesting...if you happen on the patent link, I'd be interested in a PM from you with the link. I'd like to check it out myself.

Question is, is it putting out more energy than is being inputted to the system?...
fwiw, if you want more discussion, pull the "best answer" from my post above. People re much more likely to respond to an UNanswered question than one that's been signed off by the author as a closed case...
owendrake (author)  seandogue7 years ago
thanks for the completely un-selfish advise. good lookin out!
The guy is pumping a lot of RF into the sample from a big electrically-powered device, Popular Science will publish anything - look in the back at the advertisements...
The notion that "viable energy sources have been squashed and hidden from the world for decades" is usually put about by:
- People who are trying to make money by selling "free energy" devices.
- People who refuse to believe that such "free energy" devices aren't possible.
- People who like the ideas but find it easier to understand simple conspiracy theories than physics.

L

jtobako7 years ago
Electrical energy is relatively cheep and easy to create, but reaction mass is difficult to manufacture or bring with.

A probe launched from earth needs a huge amount of fuel to escape gravity, from the moon or mars, much less.  So you could send a 'gas station' out ahead so that there would be 'cheap' gas that you wouldn't have to pay as much for.
"easy to create"

<coughs>  erm..."produce"...energy can neither be created or destroyed.

:-)
Yet it can be 'lost'...

Where was everything at Big Bang -.0000000001 second?
"Yet it can be 'lost'."

That's debatable and is yet little more than an interesting academic possibility.

I think we sometimes get too caught up in these blackhole oddities and fail to see the stars for the dark matter. We can debate the existence of warp drives, transporters, dark matter, and information loss in black holes to death, literally, while failing to achieve even one off world colony while the debate rages....doesn't make much practical sense to be to quibble over details that have no practical use in our sphere of influence.

Kinda like worrying about the price of fried grasshoppers in rural China while trying to get the corn to grow on a farm in the middle of Iowa. "I'm not doin nuffin til I figure this fried grasshopper thing out," said Farmer McDuff...And so Farmer McDuff's field lay fallow that year, the family starved, lost the farm, old Farmer McDuff died the next year, (still consumed by the fried grasshopper debate), his daughter was sold off the Las Vegas's whore houses, the wife became an alcoholic and faded from sight, and their two sons began committing robberies, until they were both shot by police after a buggled burglery... One survived, spent ten year in jail, and now works as a floor sweeper at a factory in Detroit.

That is, I'm not saying it's not of academic value, but practical? Using the idea of "cannot be created or destroyed" allows us to exploits calculations that result in real world construction. Always fretting about that tidbit that falls into a black hole would do little more than unnecessarily clutter the process. We live on a little planet, around one of some 200 billion stars in our galaxy alone....we don't need to get to the other side, we need to support our burgeoning population and maybe get to a few other worlds in the near future so that that ever growing population doesn't reach a point of collapse under the sheer weight of its consumption of finite local resources...
Laws of Thermodynamics, Number Three.