Hydrogen Power

[LaserCool]

We've already solved this for gasoline, so why not? (In fact, despite the problems of producing, transporting, storing and selling gasoline; we've actually created a system for the distribution of many different forms of gasoline and diesel.)

Storing a pressurized gas is difficult enough, but long-term strorage of hydrogen is nearly impossible; there's too much diffusion through the containers. Remember, we're dealing with the smallest of atoms, the diffusion rate is high because it literally slips through the structure of the container.

Hydrogen can also be produced by other energy sources, which means we can diversify our energy production - which is another big advantage. We also gain a lot of flexibility since we can use (practically) any energy source to drive our cars: if we had an energy crisis today, we would not be able to redirect the energy that's used for space heating or heavy industry to road transportation, or vice versa..)

Not exactly. As stated before, we still need a centralized energy source to make hydrogen, which will require petroleum, coal or nuclear for the forseeable future. We're still dependent upon the same energy sources as before, just one step removed.

In the case of cracking petrochems, we're still talking oil.

Maybe there's a value in flexibility, but it's far more logical then to push for electric cars. The electric distribution system already exists, and there's no need for vastly new technology.

To me, this hydrogen thing is no different than the hula-hoop, a passing fad.

Secondly, while burning oil to produce hydrogen won't reduce the emissions of CO2, it might reduce the emmisions of other pollutants that's caused by burning gasoline - such as CO, sulphur dioxide, nitrogen oxides and other..)

Centralizing pollution doesn't mean reduced pollution. A large amount of radiological pollution is centralized in Chernobyl, does that make it "better"?

Also, gas-buring cars still have to meet emissions standards that make them vastly cleaner than 30 years ago. Granted, incomplete combustion of most fuels (wood, petroleum, coal) is going to produce NOx, SOx, CO and CO2; but the technology of gas-burning has made air quality vastly better.

Here's a problem though-oil and gas are the most compact, stable and easily portable energy sources technology to date has made availible to us. I'm OK with that. I accept, for the time being, that oil is the best thing going.

Some forms of energy storage might be cleaner, though - and even if it can't be said to be cleaner in all regards, it might still be advantageous to use a mix of energy storage forms, to "spread the problem evenly around", so to speak..)

The only "clean" energy I can think of is electricity, but you just can't store it effectively. Every form of storeable energy involves some kind of pollution (including hydrogen; if you haven't heard, it has ozone-depleting properties).

Last I checked, we did use a form of mixed energy storage - coal, oil, nuclear, hyrdoelectric. I just don't see how hydrogen is supposed to replace any of this in an efficient cost-effective way.

That hydrogen fuel cells are not a silver bullet that solves all our energy and pollution problems, doesn't mean that it's no better than the status quo..)

The fact is it's no better than that status quo. It'll require huge investments of infrastructure that don't offer any clear payoff. At best, it's another step in the petroleum chain we already have, lowering the efficency of fuel in the name of centralizing one kind of pollution.

BTW, I wonder how people will respond to the idea of driving around with a pressurized tank of explosive gases. Granted, gasoline is highly explosive under the right conditions, but tell me how we can crash-proof a hydrogen tank without undoing all the benefits of hydrogen power with armor plating.

I believe this image might do a lot to deter hydrogen powered cars:

 

[Jon_in_london]

Storing a pressurized gas is difficult enough, but long-term strorage of hydrogen is nearly impossible; there's too much diffusion through the containers. Remember, we're dealing with the smallest of atoms, the diffusion rate is high because it literally slips through the structure of the container.


BTW, I wonder how people will respond to the idea of driving around with a pressurized tank of explosive gases. Granted, gasoline is highly explosive under the right conditions, but tell me how we can crash-proof a hydrogen tank without undoing all the benefits of hydrogen power with armor plating.

You can store hydrogen in metal oxides cant you? which solves the problem (almost)

/searches for a link.

 

[Ziggurat]

I believe this image might do a lot to deter hydrogen powered cars:

True, which is really unfortunate, since hydrogen wasn't the real culprit in the hindenburg disaster. Even the photo shows this pretty clearly - hydrogen has an almost invisible flame. What you see burning there is essentially thermite, a combination of aluminum powder and rust, that can burn hot enough to melt through steel. This unfortunate combination of materials was used to waterproof the fabric and reflect sunlight, but once it ignited from a spark, there was no stopping it.

http://www.unmuseum.org/hindenburg.htm

 

[Jon_in_london]

True, which is really unfortunate, since hydrogen wasn't the real culprit in the hindenburg disaster. Even the photo shows this pretty clearly - hydrogen has an almost invisible flame. What you see burning there is essentially thermite, a combination of aluminum powder and rust, that can burn hot enough to melt through steel. This unfortunate combination of materials was used to waterproof the fabric and reflect sunlight, but once it ignited from a spark, there was no stopping it.

http://www.unmuseum.org/hindenburg.htm

German engineering.........?

Anyone know anything about metal hydrides as hydrogen storage material? Seems to do away with the problem of carrying around pressurised H2.

 

[Leif Roar]

Storing a pressurized gas is difficult enough, but long-term strorage of hydrogen is nearly impossible; there's too much diffusion through the containers. Remember, we're dealing with the smallest of atoms, the diffusion rate is high because it literally slips through the structure of the container.

I have seen no numbers that has convinced me that storing, transporting and distributing hydrogen for use in personal vehicles is an unsurmountable problem. The fact that a lot of money and effort is invested in the research and development of hydrogen fuel cells, suggests to me that neither do many others.

Not exactly. As stated before, we still need a centralized energy source to make hydrogen, which will require petroleum, coal or nuclear for the forseeable future. We're still dependent upon the same energy sources as before, just one step removed.

My point was that in case of an energy crisis we could shift our use of energy with more flexibility. When there's a draught, we prohibit the use of water for watering lawns. Today we can't switch the energy we use for personal (or goods) transportation to space heating, or vice versa.

In the case of cracking petrochems, we're still talking oil.

We're not, however, talking about gasoline. That is a significant difference.

Maybe there's a value in flexibility, but it's far more logical then to push for electric cars. The electric distribution system already exists, and there's no need for vastly new technology.

Perhaps - but there are large obstacles for replacing current cars with electric ones, and electric cars bring with them their own problems. Those obstacles and problems might be even worse than those involved with using cars based on hydrogen fuel cells.

To me, this hydrogen thing is no different than the hula-hoop, a passing fad.

Perhaps. Then again, perhaps not. It's certainly a valid possibility, and it's certainly a valied field of research and development.

Centralizing pollution doesn't mean reduced pollution. A large amount of radiological pollution is centralized in Chernobyl, does that make it "better"?

When it comes to combustion, centralized do mean less pollution - there is a huge difference in the amount of pollution-prevention and general regulation of the combustion process you can do at a plant and what you can do in a car.

Centralizing pollution is also an advantage in some cases, since it is easier to contain and process - in the same way that centralizing dust in your vacuum cleaner is better than having it spread out across the room. That said, in some cases it is an advantage to distribute the pollution to dillute it so much it's no longer a problem. The exhaust from combustion is one example where there's no major disadvantage in centralizing the pollution.

Also, gas-buring cars still have to meet emissions standards that make them vastly cleaner than 30 years ago. Granted, incomplete combustion of most fuels (wood, petroleum, coal) is going to produce NOx, SOx, CO and CO2; but the technology of gas-burning has made air quality vastly better.

Certainly - but that doesn't mean that the emmisions have become low enough, or that hydrogen fuel cell powered cars wouldn't be even better.

Here's a problem though-oil and gas are the most compact, stable and easily portable energy sources technology to date has made availible to us. I'm OK with that. I accept, for the time being, that oil is the best thing going.

I don't agree with your assessment. Oil and gasoline are certainly the most economic way of transporting energy for certain uses, but they are not the most compact energy storage, nor are they the most stable or the most easily transportable. Coal, for instance, is both more stable and easier to transport.

Gasoline is the overall best solution for vehicle transportation with today's technology and today's oil-prices. That doesn't mean we shouldn't be looking for a better solution or try to develope new technology which will change that situation.

The only "clean" energy I can think of is electricity, but you just can't store it effectively. Every form of storeable energy involves some kind of pollution (including hydrogen; if you haven't heard, it has ozone-depleting properties).

I very specifically stated that we couldn't get "clean energy", so I don't see what you are arguing against here.

Last I checked, we did use a form of mixed energy storage - coal, oil, nuclear, hyrdoelectric. I just don't see how hydrogen is supposed to replace any of this in an efficient cost-effective way.

I think you're slightly mixing up energy production with energy storage. (One generally don't think of hydroelectric power as "energy storage" - even though you can store energy as water in the reservoirs.)

Why do you believe that hydrogen can't be used cost-effectively as a way of storing energy?

The fact is it's no better than that status quo. It'll require huge investments of infrastructure that don't offer any clear payoff. At best, it's another step in the petroleum chain we already have, lowering the efficency of fuel in the name of centralizing one kind of pollution.

How do you know it's not better than the status quo? To my eyes there are clear advantages to it, which I've stated in my original post.

BTW, I wonder how people will respond to the idea of driving around with a pressurized tank of explosive gases. Granted, gasoline is highly explosive under the right conditions, but tell me how we can crash-proof a hydrogen tank without undoing all the benefits of hydrogen power with armor plating.

If cars using hydrogen fuel cells can be made safe enough, it will not be an issue. You're assuming that it's going to be impossible to make them that safe, but I don't see why that should be.

I believe this image might do a lot to deter hydrogen powered cars:

Please. You might as well argue that since the Titanic sank, we shouldn't be building ferries.

(Edited to fix mangled Quote tags)

 

[Leif Roar]

German engineering.........?

Anyone know anything about metal hydrides as hydrogen storage material? Seems to do away with the problem of carrying around pressurised H2.

I don't know about that, but I came across this link http://www.smlassociates.com/glassspheres.htm which presents a rather ingenious suggestions for storing H2 for use.

 

[Chad Noles]

FWIW,these guys seem to have a novel way of approaching the hydrogen generation problem….http://solar-h.com/introduction1.html
There can be many ways of generating hydrogen that don’t envolve “cracking” petroleum.You can find some informative articles about hydrogen and power usage in general at http://www.homepower.com/ They have many free downloadable articles covering all types of energy questions,Check them out.Click on “Magazine”and look under “Files and Downloads”.Some of these files include,” Solar Hydrogen Production by Electrolysis”,” Hydrogen Storage (Make a Hydride Storage System)”,and “Fuel Cells and Hydrogen Electrolyzer”.

 

[RedCoat]

Re: Hydrogen generation

...it's mostly an excuse to let car manufacturers off the hook from having to take steps now that we DO have the technology to implement. Is anyone else embarassed that there isn't a single hybrid vehicle available from US manufacturers?

Being able to do something does not always imply that it can be done profitably. Right now (for at least one manufacturer) it has been determined that it costs significantly more to produce a hybrid car than it's worth in the market.

There is no conspiracy, as far as I am aware of, on the part of auto manufacturers to purposely NOT make hybrid vehicles. The car market is extremely competitive, margins are very low, and business decisions have to be made. Cut the car companies some slack - we've made a lot of progress and we're getting better all the time. Cars are cleaner now than they've ever been, and the standards get tougher every year.

Sorry if this sounded like a rant, but it's a subject I feel strongly about. Peace.

 

[Ziggurat]

Re: Re: Hydrogen generation

Being able to do something does not always imply that it can be done profitably. Right now (for at least one manufacturer) it has been determined that it costs significantly more to produce a hybrid car than it's worth in the market.

Maybe, but the Japanese manage to do it fine, and seem to be able to sell hybrid vehicles in the US, why can't we? There's other things that kind of make you wonder, like GM recalling its leased electric cars and refusing to let the leasors buy them. I'm not claiming conspiracy, but I do think that Detroit does not take fuel efficiency very seriously.

There is no conspiracy, as far as I am aware of, on the part of auto manufacturers to purposely NOT make hybrid vehicles. The car market is extremely competitive, margins are very low, and business decisions have to be made. Cut the car companies some slack - we've made a lot of progress and we're getting better all the time. Cars are cleaner now than they've ever been, and the standards get tougher every year.
[/B]

Cleaner isn't enough, they've got to be more fuel efficient as well. And in that regard we're not making any significant progress (SUV's have offset the gains that were made), and the standards are hardly moving at all. I understand that car companies have to behave selfishly, that's how the market works. But the problem has been exacerbated by things like tax cuts for SUV purchases that encourage businesses to buy inefficient cars rather than efficient ones. If government incentives went the other way (or at least didn't provide any incentive) then car companies would have an easier time (though perhaps less profitable but that's OK) making and selling fuel-efficient cars.

Sorry if this sounded like a rant, but it's a subject I feel strongly about. Peace. [/B]

No, it didn't sound like a rant, this is a pretty civil discussion.

 

[jj]

Best thing to do would be to fit each car with a windmill generator to spilt the hydrogen first. But since its not practical to have one big windmill, we should have lots of little windmills all over the car- each attached to its own little electrolysis aquifer for H2 generation. Purified H2 should then be piped to a centralised storage facility in the back seat of the car before being fed into the fuel cell. Of course the only problem is that the faster the car goes, the more wind and thus more fuel being produced. It would therefore be difficult to slow the car down once it starts to accelerate and this would result in a fatal crash, however, if the ecxess hydrogen produced could be fed into a secondary storage unit, this could be discharged at collection points across the road network (a bit like a gas- station but the other way round) and fed to power plants which would replace damaging nuclear and fossil fuel burning power plants to cool/heat our homes and provide us with all our power requirements and also Im completely mad.

Is there a reason for your ridicule? Water splitting via nuclear energy is an entirely valid option.

By the way, Jon, how much radiation does a coal-fired power plant release into the atmosphere. Don't bother saying "zero", please.

 

[jj]

You can store hydrogen in metal oxides cant you? which solves the problem (almost)

/searches for a link.

I believe that would be hydrides, for which the answer is yes. The technology is still way new, but the reactions are well known.

 

[jj]

True, which is really unfortunate, since hydrogen wasn't the real culprit in the hindenburg disaster.

Well, I did notice that the same author also had to bring up Chernobyl, and ignore the points about using a clean source of energy, like nuclear, to make H2.

 

[TillEulenspiegel]

If you're trying to tell us that a fuel cell can run on only water (and air, I suppose), you're either trying to pull a fast one, or you've been taken in yourself. Can you detail the supposed chemical reaction that powers the cell?

Jeremy

http://www.eere.energy.gov/hydrogenandfuelcells/fuelcells/types.html#rfc

Regenerative fuel cells produce electricity from hydrogen and oxygen and generate heat and water as byproducts, just like other fuel cells. However, regenerative fuel cell systems can also use electricity from solar power or some other source to divide the excess water into oxygen and hydrogen fuel—this process is called "electrolysis." This is a comparatively young fuel cell technology being developed by NASA and others.

A basic overview from the DOE. (see link above)

Unfortunatly many documents are in pdf format but this is one paper describing the catalytic process.This paper was published in the Journal of the Electrochemical Society

http://216.239.33.100/search?q=cach...mistry+regenerative+fuel+cells&hl=en&ie=UTF-8

 

[toddjh]

Regenerative fuel cells produce electricity from hydrogen and oxygen and generate heat and water as byproducts, just like other fuel cells. However, regenerative fuel cell systems can also use electricity from solar power or some other source to divide the excess water into oxygen and hydrogen fuel—this process is called "electrolysis."

Then the fuel cell doesn't "run on water," like you stated. It runs on hydrogen, created by sunlight. I also have severe doubts that solar-powered electrolysis could create enough fuel to power the average car. It seems to me you'd be better off using the solar energy to charge a battery instead and go with an all-electric vehicle, since no doubt a lot of the power is lost to heat in the electrolysis process.

Jeremy

 

[TillEulenspiegel]

Now your just engaging in polemics. The base components needed for the system to function is water ( not O2 and H ) and electricity. The water ( pure water yes ) supplies the constituent elements that are separated to O and H, solar cells supply partial E ( to both the cell and the charging system )and the storage batteries provided storage and current on demand.. Occasional charging by house current ( courtesy of the local power barons) is a given but is nominal ..now..with the technology at its infant stage. The main thrust here being one of efficiencies not of brute force
"Then the fuel cell doesn't "run on water," like you stated. It runs on hydrogen, created by sunlight"

No it runs on water which broken down by electrolysis. Also the sun does not create hydrogen it generates electricity which allows the electrolytic process to function . An internal function of the cell as I described. I did not try to assemble a car in my post , rather point out that in the quest for renewable, efficient, portable energy source there exists a technology , the in its embryonic stage offers all these and seems to offer greater promise.

 

[Agammamon]

So internal combustion engines run on water, with a little carbon added then? After all it is sunlight that combined the existing raw materials and then geophysical processes that turned 'em into oil.

And its not "engaging in polemics", rather its "bandying semantics".

 

[toddjh]

Now your just engaging in polemics. The base components needed for the system to function is water ( not O2 and H ) and electricity.

It's the "and electricity" part, which you brush aside, that is my main concern. If the the fuel cell is running completely off O2 and H2 formed by electrolysis of water, then the cell can produce no more energy than that which was used to electrolyze the water. Since you name solar energy as the means for doing that, that means that the fuel cell can produce no more energy than the photovoltaic cells can.

Since solar cars have not, as yet, been made anywhere near practical for the average driver, and your solar-powered fuel cell will incur additional efficiency losses from the added step, I don't see how this kind of system could be workable -- especially since the car would have to carry the PV system, the electrolysis system, and the fuel cell.

I also fail to see the advantage of this kind of system. Hydrogen still needs to be produced for the fuel cell to run; you're just moving the production step from a central location to each individual car. This seems like a terribly inefficient way of producing hydrogen. Even if you want to limit yourself to solar energy, it makes more sense to have a permanent hydrogen production facility someplace that has a lot of sun, where you can take advantage of the greater input as well as the economy of scale. How does your self-electrolyzing fuel cell work during the winter, or in cloudy regions?

The water ( pure water yes ) supplies the constituent elements that are separated to O and H, solar cells supply partial E

Partial E? They'd have to provide the entire E to run the whole system! True, you can stretch it out over a period of time, but there's only so many hours of sunlight in a day.

No it runs on water which broken down by electrolysis. Also the sun does not create hydrogen it generates electricity which allows the electrolytic process to function.

Okay, then a fission reactor runs on hydrogen along with energy from a supernova to convert it into U-235.

Jeremy

 

[daver]

Re: Re: Re: Hydrogen generation

Maybe, but the Japanese manage to do it fine, and seem to be able to sell hybrid vehicles in the US, why can't we?

The last i heard, Japan was selling hybrid cars at a loss. That may have changed.

 

[daver]

I believe that would be hydrides, for which the answer is yes. The technology is still way new, but the reactions are well known.

Hydride storage is also heavy--commercial hydrides can store about 1% hydrogen by weight. 20 pounds of hydrogen (roughly the equivalent of 10 gallons of gas) would take a 2000 pound tank. They're working on getting the weight down, but it's still going to be a major performance hit.

 

[arcticpenguin]

Now your just engaging in polemics. The base components needed for the system to function is water ( not O2 and H ) and electricity. The water ( pure water yes ) supplies the constituent elements that are separated to O and H, solar cells supply partial E ( to both the cell and the charging system )and the storage batteries provided storage and current on demand.. Occasional charging by house current ( courtesy of the local power barons) is a given but is nominal ..now..with the technology at its infant stage. The main thrust here being one of efficiencies not of brute force
"Then the fuel cell doesn't "run on water," like you stated. It runs on hydrogen, created by sunlight"

No it runs on water which broken down by electrolysis. Also the sun does not create hydrogen it generates electricity which allows the electrolytic process to function . An internal function of the cell as I described. I did not try to assemble a car in my post , rather point out that in the quest for renewable, efficient, portable energy source there exists a technology , the in its embryonic stage offers all these and seems to offer greater promise.

Way, way impractical. Have you seen solar cars? I've seen them; they are built of high-tech lightweight components and stripped of all components except the essentials. Almost all their upper surface is dedicated to solar panels. They have enough room for one driver. They don't go very fast, and they don't go at all if the sun doesn't shine. Usually they have a battery for backup, and race teams can take a penalty for externally charging their battery.

Now take that, add more room and weight for passengers and cargo and for safety and comfort systems. Suddenly it doesn't work so well.

Add even more weight for a fuel cell and an electrolysis system: H2O has a mass 9 times that of the H2 you can generate from it. In a realistic hydrogen fuel cell, you get the oxygen for 'burning' the hydrogen from the atmosphere. In your scheme, you carry it around with you at all times. That's an enormous weight penalty.