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Author Topic: What do you think about, these water fuels, of the future?  (Read 6779 times)

Offline Jolly- Joliver

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Future of fuel...

Water car, youtube. FOX 26
feature=channel_video_title


Salt water fuel
feature=channel_video_title
« Last Edit: 24/03/2011 23:54:28 by Wiybit »


 

Offline Geezer

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What question would you like the members to answer?

(New topics are required to be questions.)
 

Offline Jolly- Joliver

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What do you think about, these water fuels, of the future?
« Reply #2 on: 24/03/2011 23:55:01 »
What question would you like the members to answer?

(New topics are required to be questions.)

What they think about them and what they could be used for? I suppose.
 

Offline RD

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What do you think about, these water fuels, of the future?
« Reply #3 on: 25/03/2011 02:24:22 »
Future of fuel...

Water car, youtube. FOX 26
feature=channel_video_title

Whilst possible to burn gasoline in an internal combustion engine, to generate electricity, to electrolyse water, to produce hydrogen, to burn in an internal combustion engine, energetically it doesn't make sense to do so ...

Quote
The energy efficiency of water electrolysis varies widely with the numbers cited below on the optimistic side. Some report 50–80%. These values refer only to the efficiency of converting electrical energy into hydrogen's chemical energy. The energy lost in generating the electricity is not included.
http://en.wikipedia.org/wiki/Electrolysis_of_water#Efficiency


... what they could be used for?
http://en.wikipedia.org/wiki/Oxy-fuel_welding_and_cutting#Hydrogen
« Last Edit: 25/03/2011 02:56:17 by RD »
 

Offline Jolly- Joliver

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What do you think about, these water fuels, of the future?
« Reply #4 on: 25/03/2011 03:03:14 »
Future of fuel...

Water car, youtube. FOX 26
feature=channel_video_title

Whilst possible to burn gasoline in an internal combustion engine, to generate electricity, to electrolyse water, to produce hydrogen, to burn in an internal combustion engine, energetically it doesn't make sense to do so ...

Quote
The energy efficiency of water electrolysis varies widely with the numbers cited below on the optimistic side. Some report 50–80%. These values refer only to the efficiency of converting electrical energy into hydrogen's chemical energy. The energy lost in generating the electricity is not included.

If you used solar to create the electrical charge, surely there would be a benefit, at the same time it could reduce oil useage.

 

Offline RD

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What do you think about, these water fuels, of the future?
« Reply #5 on: 25/03/2011 04:01:04 »
If you used solar to create the electrical charge, surely there would be a benefit, at the same time it could reduce oil useage.

even better : do the sunlight => hydrogen thing all in one ... Photocatalytic Water Splitting Under Visible Light

[The guy in the Youtube video you linked to didn't mention solar power:
 Personally I wouldn't buy a second-hand "water-powered" car from him ].
« Last Edit: 25/03/2011 04:16:15 by RD »
 

Offline Geezer

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What do you think about, these water fuels, of the future?
« Reply #6 on: 25/03/2011 05:01:33 »
Of course, you could even skip the solar cells and use this method to convert water into electricity.

http://www.exo.net/~pauld/activities/AlAirBattery/alairbattery.html
 

Offline RD

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What do you think about, these water fuels, of the future?
« Reply #7 on: 25/03/2011 06:29:43 »
Of course, you could even skip the solar cells and use this method to convert water into electricity.

http://www.exo.net/~pauld/activities/AlAirBattery/alairbattery.html

A solar cell could produce power (or split water) as long as it was illuminated: so during daylight hours, every day, for years.

That alumunium-carbon "airbattery" will only produce power until the aluminum is all oxidised: minutes / a few hours.

[It takes "prodigious amounts" (a helluva lot) of electricity to make aluminium metal].
« Last Edit: 25/03/2011 06:36:35 by RD »
 

Offline Madidus_Scientia

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What do you think about, these water fuels, of the future?
« Reply #8 on: 25/03/2011 12:41:48 »
Indeed. It's a method of storing energy, not a source of energy.
 

Offline Geezer

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What do you think about, these water fuels, of the future?
« Reply #9 on: 25/03/2011 16:52:11 »
Of course, you could even skip the solar cells and use this method to convert water into electricity.

http://www.exo.net/~pauld/activities/AlAirBattery/alairbattery.html

A solar cell could produce power (or split water) as long as it was illuminated: so during daylight hours, every day, for years.

That alumunium-carbon "airbattery" will only produce power until the aluminum is all oxidised: minutes / a few hours.

[It takes "prodigious amounts" (a helluva lot) of electricity to make aluminium metal].

Well, yes, but it still "uses" water  ;D
 

Offline Jolly- Joliver

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What do you think about, these water fuels, of the future?
« Reply #10 on: 25/03/2011 17:02:47 »
Of course, you could even skip the solar cells and use this method to convert water into electricity.

http://www.exo.net/~pauld/activities/AlAirBattery/alairbattery.html

A solar cell could produce power (or split water) as long as it was illuminated: so during daylight hours, every day, for years.

That alumunium-carbon "airbattery" will only produce power until the aluminum is all oxidised: minutes / a few hours.

[It takes "prodigious amounts" (a helluva lot) of electricity to make aluminium metal].

Could you not encourage the oxidisation? What if you used Aluminum flakes? or aluminum dust? once the dust is used add more?
 

Offline Geezer

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What do you think about, these water fuels, of the future?
« Reply #11 on: 25/03/2011 18:00:52 »
Of course, you could even skip the solar cells and use this method to convert water into electricity.

http://www.exo.net/~pauld/activities/AlAirBattery/alairbattery.html

A solar cell could produce power (or split water) as long as it was illuminated: so during daylight hours, every day, for years.

That alumunium-carbon "airbattery" will only produce power until the aluminum is all oxidised: minutes / a few hours.

[It takes "prodigious amounts" (a helluva lot) of electricity to make aluminium metal].

Could you not encourage the oxidisation? What if you used Aluminum flakes? or aluminum dust? once the dust is used add more?

No. The aluminium has to be in the form of an electrode - a thing that you can make an electrical connection to.

But I think you are missing the most important point. As RD observes, it's not really running on water. It's oxidizing aluminium to produce energy. The aluminium was originally manufactured from aluminium oxide (bauxite), but that process consumes an enormous amount of energy, and the amount of energy released by converting the aluminium back into an oxide has to be less than the amount of energy used to produce the aluminium in the first place.

Unfortunately, there is an enormous amount of scientific theory and evidence to support that conclusion, but basically, it boils down to "there is no free lunch". Likewise, trying to extract energy from water without putting in more energy than you get out is impossible, and anyone who claims otherwise is either someone who does not know much really basic science, or is a con artist.

The only exception to this would be some sort of atomic fusion process, and people are working on that, although, even then, you are still only releasing energy that was previously stored within the structure of atoms.


 
 

Offline Bored chemist

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What do you think about, these water fuels, of the future?
« Reply #12 on: 25/03/2011 18:07:29 »
 

Offline Jolly- Joliver

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Offline Jolly- Joliver

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What do you think about, these water fuels, of the future?
« Reply #14 on: 25/03/2011 22:55:33 »
Of course, you could even skip the solar cells and use this method to convert water into electricity.

http://www.exo.net/~pauld/activities/AlAirBattery/alairbattery.html

A solar cell could produce power (or split water) as long as it was illuminated: so during daylight hours, every day, for years.

That alumunium-carbon "airbattery" will only produce power until the aluminum is all oxidised: minutes / a few hours.

[It takes "prodigious amounts" (a helluva lot) of electricity to make aluminium metal].

Could you not encourage the oxidisation? What if you used Aluminum flakes? or aluminum dust? once the dust is used add more?

No. The aluminium has to be in the form of an electrode - a thing that you can make an electrical connection to.

But I think you are missing the most important point. As RD observes, it's not really running on water. It's oxidizing aluminium to produce energy. The aluminium was originally manufactured from aluminium oxide (bauxite), but that process consumes an enormous amount of energy, and the amount of energy released by converting the aluminium back into an oxide has to be less than the amount of energy used to produce the aluminium in the first place.

Unfortunately, there is an enormous amount of scientific theory and evidence to support that conclusion, but basically, it boils down to "there is no free lunch". Likewise, trying to extract energy from water without putting in more energy than you get out is impossible, and anyone who claims otherwise is either someone who does not know much really basic science, or is a con artist.

The only exception to this would be some sort of atomic fusion process, and people are working on that, although, even then, you are still only releasing energy that was previously stored within the structure of atoms.
 

As you say it has to be in connection with an electical source, so you use electrodes, my own point was that you could find a way to increase the oxidisation, having an electrode made of carbon surrounded by an amount of aluminium designed to optimise the oxidisation process surely could assist the process? And yeald a benefit?
 

Offline Geezer

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What do you think about, these water fuels, of the future?
« Reply #15 on: 26/03/2011 03:10:28 »
I'm sure there are lots of ways it might be improved, but it's still simply a chemical battery. Once the aluminium is oxidized, the battery stops producting electrical energy.

This topic is about "water fuels". Despite the fact that this battery uses water as an electrolyte (just like a lot of other batteries), it is not fueled by water.
 

Online syhprum

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What do you think about, these water fuels, of the future?
« Reply #16 on: 26/03/2011 10:47:04 »
This device is essentially a device for burning aluminium as fuel, aluminium costs approximately the same as highly taxed petrol (gasoline) in the UK perhaps our Bored Chemist could tell us how much energy is derived per kg of each fuel.

The best values I can find are 47.3 MJ/kg for highly taxed gasoline 30 MJ/kg for untaxed aluminium.
« Last Edit: 26/03/2011 14:38:47 by syhprum »
 

Offline Bored chemist

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What do you think about, these water fuels, of the future?
« Reply #17 on: 26/03/2011 15:41:32 »
Sorry to disappoint you but I'm afraid I can't be bothered to check the energy / Kg.
There's no point.
Whatever source of energy is used to make the aluminium could be used to drive a car directly.
Doing that would avoid the losses that are inevitable from adding another stage to the process.
So, whatever the numbers are, I already know the answer.

It's not a sensible plan.

The simple truth is that water isn't a fuel.
And it won't be one unless and until we get nuclear fusion sorted out.
 

Offline Jolly- Joliver

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What do you think about, these water fuels, of the future?
« Reply #18 on: 26/03/2011 18:29:59 »
I'm sure there are lots of ways it might be improved, but it's still simply a chemical battery. Once the aluminium is oxidized, the battery stops producting electrical energy.

This topic is about "water fuels". Despite the fact that this battery uses water as an electrolyte (just like a lot of other batteries), it is not fueled by water.

OK what if you rotated? What I mean is, what if you developed a system, say ten carbon electrodes, one is in the battery oxidising, when finished, it leaves the battery a new one enters, the last one in gets cleaned, then has new aluminum attached to it? It then rotates around and around with a consistent source of newly made electrodes.

As an example you have an aluminum dust compartment with aluminum filings the newly cleaned rod rolls in that collects new aluminium for oxidisation? so the process goes around continually til all the aluminium filings are gone.

Would that be better?
 

Offline Geezer

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What do you think about, these water fuels, of the future?
« Reply #19 on: 26/03/2011 19:00:20 »
I think we have conclusively established that water is not a fuel, so I'm going to lock this thread now.

If you want to start a new topic that asks a specific question about a particular type of battery, feel free.
 

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What do you think about, these water fuels, of the future?
« Reply #19 on: 26/03/2011 19:00:20 »

 

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