Hydrogen Fuel produced by Electrolysis

Discussions related to engineering and its applications. From civil and mechanical to aeronautic and robotics, etc.

Is hydrogen fuel via electrolysis a reasonable solution?

Yessum
9
56%
Nahhh
7
44%
 
Total votes : 16

Hydrogen Fuel produced by Electrolysis

Postby Navi00 on September 4th, 2006, 1:15 pm 

I was wondering what everyone's thoughts on hydrogen fuel were.

Have you heard of it? Experimented with it?

I went through a sort of phase when I was obsessed with electrolysis and hydrogen fuel, thanks to a neighbor who was absolutely crazy about the idea.
I'm all-for altnerative energies but I learned that there were some major flaws with this system.

Essentially the process of electrolysis is very simple, you take ionized water with NaCl, drop two electrodes into it and send a current across them. The current splits the water into H2 and O2, very basic chemistry in just about every high school text book in N. America.

Then you take these gases, filter them through something or another and ignite them! I remember as a sophomore in high school sitting at my make-shift laboratory in my basement waiting for pressure to build up from the tube I was collecting H2 gas in and lighting a match.. needless to say I didn't go back downstairs for a few weeks.

So what's everybody's thoughts on hydrogen power?
Navi00
 


Postby Cyndi Loo on September 5th, 2006, 3:41 am 

Thanks Navi for a great topic!

Here is a link to a site that is using a combination of solar, electrolysis & hydrogen to fuel a bus.

http://www.hygen.com/solar_hydrogen_vehicle_project.htm

There is a great pictorial representation of how the process works with this link. I will try to go back in the morning when I get off from work and upload it from home.

Pertaining to flaws, I thought there were some major flaws with hydrogen vehicles, but some SCF posters demonstrated the kinks have been worked out.

There are two types of hydrogen generation methods for vehicles, combustion and fuel cell. The electrolysis hydrogen method uses fuel cells.

http://www.sciencedaily.com/encyclopedi ... en_vehicle

Fuel cells have been very difficult to work with hydrogen in the past. There have been some improvements made to fuel cells.

http://www.eurekalert.org/pub_releases/ ... 082205.php

A single fuel cell does not produce enough energy to power a car. So fuel cells are stacked, with a bipolar plate between each cell through which electrons are conducted. The hydrogen fuel and oxygen, which are part of the fuel cell chemistry, enter the plate through channels along the face on each side of the plates. Creating the channels in the bipolar plate is a manufacturing challenge. About 29 percent of the cost of a fuel cell stack is the bipolar plate, and machining channels into the plates is a significant factor. So researchers at Virginia Tech are developing compression moldable composite bipolar plates with channels included.

Progress, I guess.

C
Cyndi Loo
 


Postby Cyndi Loo on September 5th, 2006, 9:35 am 

[img][url=http:240:214]http://upload4.postimage.org/1054541/flowcht.jpg[/img][/url]
Cyndi Loo
 


Postby Navi00 on September 6th, 2006, 6:25 am 

The only problem I see with that is the truck would have to store tanks of hydrogen in it, and that's incredibly dangerous. If there was a way to produce enough hydrogen on demand through electrolsys of water... Like using the car's montion to generate electricity. ( Refering to the combustion method )
Navi00
 


Postby Cyndi Loo on September 6th, 2006, 6:28 am 

Yes. I can see how that could be an issue. I read a while back there are small portable hydrogen refueling options. You could just carry the fuel pump with you everywhere you go!
Cyndi Loo
 


Propane or methanol

Postby turbine on September 10th, 2006, 2:14 pm 

I had a conversation about fuel cells with the instructor of the process plant technology program a couple of years ago. He said that they can achieve a very high efficiency using natural gas or methanol; however the process of refining these fuels to the quality required was some what prohibitive. One of the problems with pure hydrogen is even when on fire you can not see the flame. There are other issues. Air is required for the process. This air must be extremely well filtered, a bus running off of a fuel cell in Detroit had to replace all of the membranes because of contamination. This was caused just be following a diesel fuel bus.
turbine
 


Hydrogen Fuel

Postby Gavilan on November 3rd, 2006, 7:21 pm 

What is "Bond Energy"?

How much energy does it take to produce Hydrogen from water?
Gavilan
 


Bond energy

Postby turbine on November 11th, 2006, 10:31 am 

This is way out of my field but I will give it a try. I have no idea how much energy it takes to brake the bonds that hold water together, I am certain that it takes more energy than can be recovered. Water is very unique. The bonds that hold it together give it special properties. It takes a great deal of energy to freeze or boil water. It requires 970 BTU's to boil one pound of 212 degree F water, this is compared to about 36 BTU's to boil one pound of R-22 the refrigerant found in almost all air conditioners. Of course boiling is not decomposing.

I am certain someone out there could explain the strength of orbital bonds and the Vanderwalls ( I am sure that is misspelled) forces, sorry its just beyond my memory.
turbine
 


Postby Heron on December 14th, 2007, 5:03 pm 

You are correct in your assumption turbine.

Bond energy of water 463 kJ/mol.

Energy from 1 mole h2 285.83 kJ/mol.


Need not ponder further.


ref. Benson, University Physics 1996 revised ed.
Heron
 


Postby ele7ven on December 31st, 2007, 3:54 pm 

Here's a simple illustration of the issue.

[img:753:369]http://upload.wikimedia.org/wikipedia/en/thumb/8/8d/Battery_EV_vs._Hydrogen_EV.png/753px-Battery_EV_vs._Hydrogen_EV.png[/img]

An alternative to electrolysis is production of hydrogen from natural gas, which is much more efficient as far as the input energy goes. But then again, it uses up a viable fuel in the process, so why not just use the natural gas outright. Also, take the numbers with a grain of salt, as they can vary depending on the sources. The point is: Why use electricity to create hydrogen to create electricity, when we can use the electricity in a more direct fashion?
ele7ven
 


Postby minime on January 4th, 2008, 8:06 pm 

For any car enthusiasts. BMW are onto it with combustion as opposed to fuel cells, At the moment dual fuel systems are used.

2 links http://www.theautochannel.com/news/2004 ... 30298.html

http://auto.howstuffworks.com/bmw-h2r.htm
minime
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Postby enjoneer on May 23rd, 2008, 12:08 pm 

Heron wrote:You are correct in your assumption turbine.

Bond energy of water 463 kJ/mol.

Energy from 1 mole h2 285.83 kJ/mol.


Need not ponder further.


ref. Benson, University Physics 1996 revised ed.



This is absolutely correct, it takes more energy to rip apart a water molecule than you can get by combusting hydrogen gas. If this was not the case, plain water would be quite flammable because a big enough spark would initiate an uncontrolled and unbounded reaction.

HOWEVER, gasoline engines can produce quite a bit of electricity that is NOT used at all in the powertrain. Using excess electricity (combination of battery and alternator) allows you to convert over half of that energy (theoretically) into usable mechanical energy in a combined gas/hydrogen/oxygen combustion chamber. This would not work without the gasoline, and it would not work in an electric vehicle at all. Technically, I suppose it would work in a gas/electric hybrid, but the point would be moot because you're now taking electricity that would otherwise be used to generate mechanical energy directly.

I haven't done the math, but I bet it is technically more efficient to use electricity directly in the powertrain than generating and burning hydrogen. But which would you rather do to your car: a $100 mod to install a jar, some wires and a hose for intake, or a $10000 mod to completely convert your powertrain? Hydrogen can add quite a boost without the added weight of batteries and electric motors... so overall your energy yield may be lower but it's more useful because it's not wasted in carrying around the very system that sustains it, so it's even worthwhile at the OEM level.

Like I said, this would be a complete waste of time on something like the Chevy Volt, which is an electric vehicle that has an engine strictly for electricity generation. But because typical gasoline vehicles (or diesel, for that matter) don't use electricity to drive, they can benefit from a hydrogen boost. If you want to complain about the extra load on the alternator, look at it this way: a proper electrolysis system will drop 2-3 volts, maybe 40 amps. So let's say it consumes a constant 120W. Basically, it's not worse than plugging in your laptop through an inverter... would you say the laptop causes a significant drain on the car's electrical system?

The only issue with this is that long-term electrolysis can form a sludge, depending on the quality and composition of the electrodes and electrolyte. Using good quality materials and good engineering practices, there is really no reason to not add hydrogen boosting to your car, assuming you're willing to check the water level once in awhile, probably every oil change. If this catches on commercially, and I really wish it would, you'll probably see jugs of premixed electrolyte at the gas station like wiper fluid or transmission fluid.
enjoneer
 


Postby Highwaystar101 on May 27th, 2008, 1:08 pm 

Yesssum
Highwaystar101
 


Have you considered the fuel used to produce electricity

Postby mbeychok on June 28th, 2008, 8:15 pm 

The electrolysis of water to produce hydrogen requires electricity. The generation of electricity requires the combustion of natural gas, petroleum fuel oil or coal ... or a nuclear plant. You cannot escape those costs nor can you escape the environmental impacts of producing that electricity.

Producing hydrogen on large, industrial scale (other than hydrolysis) is currently done by the catalytic reforming of natural gas or of petroleum naphtha. Again, you cannot escape the costs of producing hydrogen nor the environmental impacts of doing so.

The only realistic ways of reducing our dependence on foreign crude oil are:

(1) Building nuclear plants to provide electric energy.
(2) Converting our tremendous resources of surface-minable coal and of shale oil (in the western USA) to synthetic fuel gas and/or synthetic crude oil ... as has been done in South Africa for decades. There are 10-15 times as many BTU's of energy in our western coal and shale resources as there are in all of the petroleum crude oil in Saudi Arabia.

It will take a large expenditure of capital but it can and has been done and it can be done with minimal environmental impacts. In the long run, it will cost less than the 12 billion dollars per month we are now spending in IRAQ and the untold billions we are spending to pay $4 to $5 per gallon for gasoline.

Milton Beychok

Industry website reference deleted as per forum guidelines -- please use the appropriate field in your user profile for advertising your website.
Last edited by mbeychok on June 28th, 2008, 9:46 pm, edited 1 time in total.
mbeychok
 


Postby Removed user on June 28th, 2008, 8:38 pm 

In another thread it was noted that a researcher has developed a method to use EM radiation to split water. Of course this is nothing new to the world as life has been doing it for billions of years. However, the method is efficient and while it naturally requires more energy than is produced this is not the point.

There are applications for a readily available and fuel and oxygen source that uses nothing more than harmless radio waves and salt water as its two chief components. Solar, tidal or wind-powered oceanic or coastal electrolysis platforms are within the technical grasp of humanity today and could provide much-needed energy alternatives to oil.

What also should be looked into with hydrogen fuel is a return to the external combustion engine. Hydrogen burns very hot (hydrogen ovens are used in sintering) and could fuel efficient steam engines for, say, railroad applications.
Removed user
 


Postby mbeychok on June 28th, 2008, 10:08 pm 

Metis, when I discussed realistic options to mitigate our dependence on foreign oil, I meant technology which has been proven to be feasible on an industrial scale. Nuclear power plants have proven they work for many years. Coal conversion into synthetic fuel gas and synthetic crude oil have also been in large scale use in South Africa for decades. We, in the United States, also have a coal gasification plant that has been in successful operation for decades in North Dakota. Design and construction of nuclear plants and coal conversion plants could start tomorrow!

Some of the options you mentioned are merely research items at present. Others have very limited large-scale operational experience. Design and construction of your options on a large-scale would require more research and more study and more experience before they could start.

Milton Beychok
mbeychok
 


Postby Removed user on June 28th, 2008, 11:06 pm 

The problem is that your coal-oil/gas plan just exchanges one fossil fuel for another, which does little to ameliorate problems such as CO2 production, acid rain, and toxic levels of mercury.

Traditionally it’s taken about 50 years to implement a new energy technology. Therefore, alternative technologies, while currently only capable of supplying a fraction of demand and at a higher price, must be developed – if not the industrialized world will be in a real mess when the fossil fuel reserves are depleted, which is inevitable, if not in the near future then at least within the foreseeable future.

Note to the reader: The above poster has a vested interested in the industry he is promoting. I'll leave it to you whether or not to consider this expertise or bias.
Removed user
 


Postby Removed user on June 29th, 2008, 1:53 am 

Like I said, mea culpa, but if you hang around the forums for long you will see where I’m coming from where advertised websites, especially those concerning energy technologies, are concerned. And notice the “smiley face” beside my comment about my choice of an avatar, which suggests that it was made in a humorous vein.

Also, dispersion of pollution is not the answer. In fact this only exacerbates the effects of heavy metal pollution. Currently children and pregnant/nursing women are recommended not to eat much tuna and to not touch swordfish at all due to the bioaccumulation of mercury in these top predators – mercury that came primarily from the burning of coal.

Of course, as oil prices skyrocket stack-scrubber technology might become more economically feasible. The problem with coal-based pollution still remains though in countries such as China and Mexico that employ few, if any, pollution controls.
Removed user
 


Postby minime on June 29th, 2008, 4:56 am 

Metis wrote:And I just thought that my avatar was some old guy like me with a beard (well I shaved recently as it got too hot). :)

You mean that it is not a picture of you, just how deceitful can you get, I am shattered.
minime
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Postby DrCloud on June 29th, 2008, 8:40 am 

Metis wrote:Like I said, mea culpa...

I'm not sure even this is necessary, Metis.

I spotted the same, undeclared conflict interested you did; you simply called it out. In doing so, you made an imprecise assumption and created an opening for protest, which came, loudly and, I have to say, dressed in considerable disingenuity.

It's quite clear, after all, that wide adoption of coal gasification and oil-shale extraction technologies will create fat new markets for atmospheric dispersion books and expertise. By touting those technologies as virtually off-the-shelf solutions, our friend conveniently glossed over a number of issues, including the greenhouse gas problem that you pointed out, as well other significant potential show-stoppers. For example, oil-shale extraction is hugely water intensive. This is something that has the folks out that way quite worried indeed.

I think that book sales are a big motivating factor here. HPH
DrCloud
 


Postby DrCloud on June 29th, 2008, 5:16 pm 

And now back to our regularly scheduled program...

I made the point in this thread that nearly everything we use for an energy source has as its ultimate source the Sun. (Nuclear and geothermal power are the two exceptions that come to mind.) It's certainly the case that there is plenty of solar energy available now to wean us off our reliance on ancient solar energy in the form of fossil fuels.

The question is how to convert that solar energy to a form that's both stored (so we can use it at night, on cloudy days, and during the winter when the sun is weaker) and portable. In situ hydrolysis of water is one obvious possibility. It doesn't matter that the process is inefficient, and the economics will change as the prices of other forms of energy change. However the hydrogen is used, it has huge potential.

And, to be clear, the only connection I have to this is that my university is involved in R&D on using the Gulf Stream to generate power using underwater turbines -- exploiting solar energy after it's first been converted by Earth's own heat engine, the atmosphere, into wind and the ocean currents. HPH
DrCloud
 


Postby Removed user on June 29th, 2008, 9:00 pm 

The argumentative exchange has been moved to the trash where it belongs. Let’s all take DrCloud’s suggestion and bring this thread back on track.

Recall the original question: “Is hydrogen fuel produced via electrolysis a reasonable alternative to fossil fuels?” To discuss this we need to look into the efficacy of converting current internal combustion engine technology to hydrogen (is it feasible?) or assess other ways that hydrogen might be used (e.g., in fuel cells or external combustion engines). Also, we need to assess the problems entailed in not only producing the hydrogen but also in storing and transporting it. Then safety issues should be addressed. Is a tank of compressed hydrogen as, more, or less dangerous than a tank of volatile petroleum? Finally, we may need to face fact that fossil fuel was a “quick and dirty” means to the end of industrialized society that can not be completely replaced by any one energy technology. Which may, in fact, not be such a bad thing as the predicament we are in now with high energy prices stems in a large part from “putting all of our eggs in one basket.”
Removed user
 


Postby DrCloud on June 29th, 2008, 9:36 pm 

Metis wrote:The argumentative exchange has been moved to the trash...

Thank you -- even though one of the posts involved was mine. Moderation is, in my view, a Good Thing.

Here's a slightly tangential contribution that addresses part of what you just raised:

One of the longer term goals of our Gulf Stream project is to apply new technologies to exploit another solar-created energy source, the ocean's thermocline, meaning the temperature difference between the warm surface water and the colder deep water. This is not a new idea by any shake, having first been looked into some 30 years ago. The US Department of Energy has sunk a ton of money into it, but it's never really come to fruition. But we think it's just too important a potential energy source to ignore.

If that temperature difference can somehow be used directly to generate electricity, though, that power could be used to hydrolyze sea water at depth -- a place where the resulting hydrogen would automatically be pressurized. Storing it down there would solve a lot of safety problems. For transport, it could then be treated much like high-pressure natural gas is now, pumped around and stored again using much the same technology. Yeah, it's dangerous, but so is methane. One advantage of all this is that it would take advantage of much of the under-sea oil & natural gas technology we have now, making it closer to realization.

The real problem with H2, I think, is the land-based infrastructure -- gas stations, safe tanks for cars, etc. Fuel cells have promise, but they're still a gleam in researchers' eyes, for the most part. But it's all quite encouraging. HPH
DrCloud
 


Postby Removed user on June 29th, 2008, 10:05 pm 

Speaking of methane, deep-sea deposits of methane hydrates might be another potential source of hydrogen. There are two major problems to using them though. One is the feasibility of deep-sea mining and the other is the fact that there is usually a biotic community, with many species found nowhere else, associated with them.

[img:417:329]http://people.whitman.edu/~yancey/bathyalscene.jpg[/img]
Removed user
 


Postby DrCloud on June 29th, 2008, 10:42 pm 

See? Those dang fossil fuels are so addicting we can't even stop talking about them!

Methane hydrates, though, are pretty interesting. Those critters you mention metabolize them, releasing (gulp!) CO2; worse, if conditions where they currently exist change radically and warm up, the methane itself could be released into the water and then the air. Various folks I know worry about that sort of thing. They're having trouble getting anyone to listen to them, but they still worry. HPH
DrCloud
 



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