Questions about a Hydrogen Economy; Scientific American

[Seafang]

In other words, burn more fossil fuels to make hydrogen? How does that help anything? Certainly not - I'm just not sure what hydrogen has to do with anything in this context. I think you probably understand the issue, but to the general public, they hear the politicians talking about a hydrogen economy and picture the hydogen materializing at the gas pump. Politicians (the people driving the issue) for the most part completely ignore the issue of manufacturing the hydrogen. And that's a dealbreaker for the whole idea. Its like talking about landing a man on the moon without first discussing how to get one in orbit around earth.

Realistically if Bush or Kerry (both have picked up the issue) succeed in getting a million hydrogen powered cars on the road in 10 years and a hundred thousand hydrogen fueling stations, where is that hydrogen going to come from? Realistically. My bet is it'll come from hydrogen manufacturing plants that either take their coal-fired electricity straight from an already overloaded grid or make their own power using oil-fired gas turbine generators. Net result: more pollution, more dependancy on domestic coal and foreign oil, and a bigger energy crisis.

Russ, has hit a raw nerve on this subject. Hydrogen is already manufactured from Hydrogen ores by industries that supply those who need hydrogen in industry. These people are not economic idiots, so it is a sure bet that they are producing that hydrogen in the most economically efficient processes currently known. the history of the chemical industry is replete with examples of new processes being developed and old suppliers being supplanted by more efficient ones.

So if ANY of the solar powered renewable bio-hydrogen processes were even remotely viable economically they would be in use already. Economic viability in a competitive market usually means energy efficient, since the cost of energy to process things is a big factor in the economics of it. So the likelihood of any new hydrogen process replacing the present methods which probably get it by processing natural gas; is slim to none.

And yes sea water is about as low on the stored chemical energy food chain as it is possible to get.

If extracting hydrogen from water was economically viable at all, then by inference it should be just as practical to extract another fuel; namely carbon, from the abundant supplies of it in the atmosphere, or the oceans, Doing that would make the whole CO2 problem moot. Not likely to happen, nor is any major shift to hydrogen.

Hydrogen vehicles such as inner city buses may make a lot of sense from a local air pollution point of view but for the mass of transportation needs it is a pipe dream; but one that Bush threw out there so the environmentallists could not say he was anti-environment. Now it is up to THEM to try and make a hydrogen economy real.

The practicality of increasing electricity generation capacity to the point where either hydrogen fuel cell or pure electric cars could totally replace the internal combustion engine, is just too silly to contemplate. We have enough problems now with regulations just getting enough electricity for electricity needs. The Nuclear opponents aren't going to sanction any massive swing to nuclear specially when it becomes apparent that breeder reactors will be necessary to make that long term viable. Fat chance in today's terrorist strewn world.

There is one other nasty problem with that lovely hydrogen picture. It also requires lots of additional energy just to get it into a storable form. The energy cost of gas compression, or the materials cost of metal hydrides, makes hydrogen a lot less pretty. Then there is all that 'clean' water vapor that will be emitted; well I suppose you could condense the water and save it in an onboard 'ungas' tank. But then water vapor is also a green house gas, and in fact is the major green house gas with by far the most influence on the environment and climate. Renewable (solar) energy sources sound like a great idea, until you realize how poorly concentrated they are. Surely they have to be used in niche situations where they make sense, as does every other energy source we have, but so far there are few real alternatives to hydrocarbons.

Arguably it would make much more sense to use the hydrocarbon fuels as we do now, and recycle the carbon. but even that only makes sense if you believe that CO2 is a significant problem to the environment. I for one do not believe it plays much role at all. With CO2 being 0.037% of the atmosphere, and water vapor as much as 4% at times, I think the problem of thermal flux balance of the Earth is not dependent on CO2 to any great extent compared to water.

 

[Ivan Seeking]

Iceland is going 100% H2 right now. They estimate that after satisfying their own needs (5%), they can sell the other 95% of the viable geothermal energy as H2. So for starters we need to look at the new energy "reserves" that can be transported as hydrogen, that would otherwise be wasted.

Then there is the nagging problem that it is in everyone's interest to stifle the demand for oil. Besides, sooner or later we will have no choice.

If extracting hydrogen from water was economically viable at all, then by inference it should be just as practical to extract another fuel; namely carbon, from the abundant supplies of it in the atmosphere, or the oceans, Doing that would make the whole CO2 problem moot. Not likely to happen, nor is any major shift to hydrogen.

How do you come up with that analogy? I'm quite sure that statement cannot be defended.

 

[hitssquad]

Oil futures speculation in the context of Hubbert's peak

Iceland is going 100% H2 right now. They estimate that after satisfying their own needs (5%), they can sell the other 95% of the viable geothermal energy as H2.

Iceland is an island. How might this H2 be delivered?

it is in everyone's interest to stifle the demand for oil. ...sooner or later we will have no choice.

Futures markets either correctly or incorrectly reflect the current value of future scarcity. Thus you are concluding that oil futures are underpriced right now, and further thus a good investment; correct?

 

[Chronos]

Hydrogen is more viable and less expensive than many may think. A number of methods are possible which could produce the hydrogen energy equivalent of gasoline for about the same price... or even less. Of course you still have the infrastructure hurdles, but, this need not take place overnight and could be solved more quickly than generally thought. Some informative links:


hydrogen from methanol
http://www.nasatech.com/Briefs/Jun02/NPO19948.html

hydrogen from coal
http://www.nuclear.com/Energy_policy/Coal_gas_news.html

hydrogen from nuclear power
http://www.businessreport.co.za/index.php?fSectionId=561&fArticleId=291054

hydrogen from sunlight
http://www.pureenergysystems.com/news/2004/09/14/6900043_Solar_Hydrogen/index.html

hydrogent from wind
http://evworld.com/view.cfm?section=article&storyid=502

fuel cells
http://www.spacedaily.com/news/energy-tech-03s.html

Technical issues of a hydrogen economy
http://books.nap.edu/books/0309091632/html/1.html#pagetop

 

[Seafang]

Iceland is going 100% H2 right now. They estimate that after satisfying their own needs (5%), they can sell the other 95% of the viable geothermal energy as H2. So for starters we need to look at the new energy "reserves" that can be transported as hydrogen, that would otherwise be wasted.

Then there is the nagging problem that it is in everyone's interest to stifle the demand for oil. Besides, sooner or later we will have no choice.




How do you come up with that analogy? I'm quite sure that statement cannot be defended.

Well it is very easy to defend Ivan. Hydrogen, when burned yields water plus some energy. Water, after the input of at least as much energy, restores the hydrogen which can be burned again or run through a fuel cell.

By the same token, carbon can be burned to yield carbon dioxide and energy. Carbon dioxide, after the input of at least as much energy restores the carbon which can then be burned again.

In both cases the element is being used as a source or transport means of energy, but you need some other source of energy for the recycling process. That other source of energy could of course be used instead of the hydrogen or carbon, so why bother with the wasteful processes or recovering hydrogen from water, or carbon from carbon dioxide.

If it is technically viable to obtain hydrogen from water to use as a source of energy, it is equally technically viable to start form the abundant CO2 and get carbon fuel from it.

Both of course don't make any sense if what you want is additional sources of energy over and above those which we already have. When the fossil fuels oil and natural gas are gone where will you get all the energy to create hydrogen ? And if you have such a source of additional energy why waste it on what is at best a zero sum game, but in practice is a massive energy wasting scheme. Or doesn't the prohibition against perpetual motion apply to you?

 

[Seafang]

Hydrogen is more viable and less expensive than many may think. A number of methods are possible which could produce the hydrogen energy equivalent of gasoline for about the same price... or even less. Of course you still have the infrastructure hurdles, but, this need not take place overnight and could be solved more quickly than generally thought. Some informative links:


hydrogen from methanol
http://www.nasatech.com/Briefs/Jun02/NPO19948.html

hydrogen from coal
http://www.nuclear.com/Energy_policy/Coal_gas_news.html

hydrogen from nuclear power
http://www.businessreport.co.za/index.php?fSectionId=561&fArticleId=291054

hydrogen from sunlight
http://www.pureenergysystems.com/news/2004/09/14/6900043_Solar_Hydrogen/index.html

hydrogent from wind
http://evworld.com/view.cfm?section=article&storyid=502

fuel cells
http://www.spacedaily.com/news/energy-tech-03s.html

Technical issues of a hydrogen economy
http://books.nap.edu/books/0309091632/html/1.html#pagetop

So we can get hydrogen from ethanol; where do we get the energy to create the ethanol in the first place; current methods of ethanol production take more energy to produce than you get from the ethanol.

Hydrogen from coal; when you remove hydrogen from coal you get a rather nasty effluent called soot; what are you going to do with all that soot other than burning it too for additional energy; why not just burn the coal itself.

Hydrogen from nuclear power; just in case you haven't noticed, all the nuclear power on Earth is currently being used to make electricity for people who need electricity. Attempts to generate more nuclear power have been stopped by environmentallists who don't like nuclear energy.

Hydrogen from sunlight; I don't see much hydrogen in sunlight; maybe they are using solar energy in some form to generate hydrogen; why not use that energy from sunlight for what you want energy for.

Hydrogen from wind; also never seen much hydrogen in the wind; perhaps the wind is being used to generate mechanical power or even electricity. Why not use that mechanical power to do work or use the elctricity for people who want electricity.

As I said if any of these schemes for making hydrogen were technically or even economically viable, they would be in use today generating industrial hydrogen. they aren't and they aren't.

It's a Ponzi scheme !

 

[russ_watters]

Futures markets either correctly or incorrectly reflect the current value of future scarcity. Thus you are concluding that oil futures are underpriced right now, and further thus a good investment; correct?

Interesting assessment - I'd think that due to today's political climate, the future scarcity is probably overcompensated for in the market price. I'll be right back...

 

[brewnog]

As I said if any of these schemes for making hydrogen were technically or even economically viable, they would be in use today generating industrial hydrogen. they aren't and they aren't.

To some extent I agree with you, and indeed as you state, some of those methods for 'mass' production of energy are not as desirable as others, and you're right to be asking "we run cars on hydrogen, so what? We still have to get the energy from somewhere."

However, you're missing the point. The key thing about hydrogen is not that it's going to be the ultimate source of energy, but an extremely efficient method of storage and distribution.

I would like to see a working comparison of the losses involved in transmitting an amount of energy over a set distance using high voltage power lines, against the energy required (in terms of trucks, trains, whatever) to transport the same amount of energy, in hydrogen form, over the same distance. Anyone?

 

[Chronos]

So we can get hydrogen from ethanol; where do we get the energy to create the ethanol in the first place; current methods of ethanol production take more energy to produce than you get from the ethanol.

Hydrogen from coal; when you remove hydrogen from coal you get a rather nasty effluent called soot; what are you going to do with all that soot other than burning it too for additional energy; why not just burn the coal itself.

Hydrogen from nuclear power; just in case you haven't noticed, all the nuclear power on Earth is currently being used to make electricity for people who need electricity. Attempts to generate more nuclear power have been stopped by environmentallists who don't like nuclear energy.

Hydrogen from sunlight; I don't see much hydrogen in sunlight; maybe they are using solar energy in some form to generate hydrogen; why not use that energy from sunlight for what you want energy for.

Hydrogen from wind; also never seen much hydrogen in the wind; perhaps the wind is being used to generate mechanical power or even electricity. Why not use that mechanical power to do work or use the elctricity for people who want electricity.

As I said if any of these schemes for making hydrogen were technically or even economically viable, they would be in use today generating industrial hydrogen. they aren't and they aren't.

It's a Ponzi scheme !

Read the links before leaping to conclusions.

 

[hitssquad]

Boron vs hydrogen as a petrol-replacing energy carrier

hydrogen is ... going to be ... an extremely efficient method of storage and distribution.

Graham Cowan has pointed out numerous times on Know Nukes that indicators seems to be pointing in the opposite direction. This is basically why Cowan proposes that boron technologies, instead of hydrogen technologies, be developed to replace fossil fuels as energy carriers:
http://www.eagle.ca/~gcowan/boron_blast.html

One could not put a hydrogen or hydrocarbon tank right next to the engine, lest it get heated and build up excessive pressure. But there's no harm if a bin full of boron bits gets warm.

a hydrogen vehicle's fuel reservoir system is more massive and much more complex than a gasoline tank, in part because of hydrogen's superlative bulk

Hydrogen at Sea
Hydrogen as fuel is lighter than petroleum, lighter even than boron, and has a nonreturning oxide. Water vapour can be dumped anywhere and hydrogen generating plants can find new water to split, or at least different water, almost anywhere. Hydrogen isn't explosion-proof like boron, but it must beat hydrocarbons and boron in the efficiency race, must it not?

Actually it comes dead last. Liquefaction energy is the culprit, and it's not a seven percent loss, it's about half. A boron carrier could go around the world the long way and still beat a hydrogen carrier. So could a carrier of plastic made from air, water, and solar energy.

Consider two power plants. Each turns 20 or 30 gigawatts of heat into 10 GW of chemical fuel. This is larger than usual for electric power plants today but an ordinary size for oil refineries.

One makes hydrogen, the other makes boron. If the boron plant has no takers for a couple of weeks, it can stack boron outside, perhaps on pallets, 40 acres six feet deep. Rain won't hurt it.

The hydrogen plant might also store two weeks' production, not, of course, in contact with the elements -- Earth and water are OK, but definitely not air or fire -- but perhaps as the inflating gas in a kilometre-wide gas supported tent 250 m high at the centre. This is about five times more area than the pallet field, and seems certain to cost more per unit area.

How big are the tanks, really? Answers are given here in terms of litres per three gigajoules, not one, because 1 GJ of fuel energy propels a typical car only about 300 km, and 1,000-km range is not very unusual:

Hydrogen - 373.8
Boron - 139.9

The 140-L entry for boron is 108 L for ash, 32 L for fuel. This is based not just on tripling the data from Ash Volumes and Boron the Dense but on multiplying them by further factors of roughly 1.5. These extra adjustments allow for imperfect packing of solids.

Below are the various light oxophiles' volumes in litres per gigajoule of oxidation potential energy.

Hydrogen - 124.59
Boron - 7.82

 

[Ivan Seeking]

Read the links before leaping to conclusions.

Yes please. There are plenty of links posted with answers to most initial questions and objections that our readers may have. Please review this and the original thread in the physics forum to learn the basics.
https://www.physicsforums.com/showthread.php?t=4127&page=1&pp=15

 

[shrumeo]

Graham Cowan has pointed out numerous times on Know Nukes that indicators seems to be pointing in the opposite direction. This is basically why Cowan proposes that boron technologies, instead of hydrogen technologies, be developed to replace fossil fuels as energy carriers:
http://www.eagle.ca/~gcowan/boron_blast.html

Didn't they already scrap boranes as rocket fuels back in the sixties because the combustion products are solid and there wasn't much of a way around it?

You end up with borates, which you then have to dispose of, unless there is a new boron fuel that has come out.

Well it is very easy to defend Ivan. Hydrogen, when burned yields water plus some energy. Water, after the input of at least as much energy, restores the hydrogen which can be burned again or run through a fuel cell.

By the same token, carbon can be burned to yield carbon dioxide and energy. Carbon dioxide, after the input of at least as much energy restores the carbon which can then be burned again.

In both cases the element is being used as a source or transport means of energy, but you need some other source of energy for the recycling process. That other source of energy could of course be used instead of the hydrogen or carbon, so why bother with the wasteful processes or recovering hydrogen from water, or carbon from carbon dioxide.

If it is technically viable to obtain hydrogen from water to use as a source of energy, it is equally technically viable to start form the abundant CO2 and get carbon fuel from it.

Both of course don't make any sense if what you want is additional sources of energy over and above those which we already have. When the fossil fuels oil and natural gas are gone where will you get all the energy to create hydrogen ? And if you have such a source of additional energy why waste it on what is at best a zero sum game, but in practice is a massive energy wasting scheme. Or doesn't the prohibition against perpetual motion apply to you?

Unless we come up with a way to mimic photosynthesis, it takes way more energy to reduce carbon dioxide than it does to split water.

Using methane as an example (from: http://www.webchem.net/notes/how_far/enthalpy/enthalpy_of_combustion.htm )

CH4(g) + 2O2(g) -> CO2(g) + 2H2O(g) DHq = -882 kJ mol-1

That means to go the other direction you need to put in 882 kJ mol-1

Using a fuel cell as the other example (from: http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/electrol.html )

H2(g) + O2(g) -> 2H2O(l) DH = -285.83 kJ mol-1

The opposite reaction would need an input of 285.83 kJ mol-1.

Since the entropy terms would probably be simliar, I'm sure the total free energy change is similar to these also. You get a lot of energy out of hydrocarbons, but to put all that energy back in is just too much for current technology to do cost effectively (I guess). So far, doing it with water to supply the whole world with power is still quite out of reach (I think).

 

[shrumeo]

Hydrogen is more viable and less expensive than many may think. A number of methods are possible which could produce the hydrogen energy equivalent of gasoline for about the same price... or even less. Of course you still have the infrastructure hurdles, but, this need not take place overnight and could be solved more quickly than generally thought. Some informative links:


hydrogen from methanol
http://www.nasatech.com/Briefs/Jun02/NPO19948.html

But you are still working with fossil fuels or their derivatives. You still have to dig things out of the ground and "burn" them. This is not a renewable resource.

hydrogen from coal
http://www.nuclear.com/Energy_policy/Coal_gas_news.html

This is just saying there is a way to extract hydrogen from another fossil fuel that you have to dig out of the ground and burn. It doesn't reduce CO2 emissions, it just saves the hydrogen.

hydrogen from nuclear power
http://www.businessreport.co.za/index.php?fSectionId=561&fArticleId=291054

If we are only going to use hydrogen fuel cells in vehicles then this might be a good way to make the hydrogen. Hydrogen fuel cells still beat batteries when it comes to mileage, so it might be a good alternative to just plugging your car up to the nuke plant.

hydrogen from sunlight
http://www.pureenergysystems.com/news/2004/09/14/6900043_Solar_Hydrogen/index.html

You know all the problems with solar anything. First the sun has to out. Second, the total efficiency is terrible with current technology. You'd have to have solar arrays the size of Kansas to provide enough H2 for the US.

hydrogent from wind
http://evworld.com/view.cfm?section=article&storyid=502

Again, the problem is that you need the wind to be blowing. Not everywhere is windy, and you'd need a windfarm the size of Massachusettes to make enough H2 for the US.

 

[Seafang]

In the other thread I posted about the process of dissociating water into hydrogen and oxygen by high temperature created with a parabolic mirror from sunlight. Efficiency is moot with this, since the energy is free. The problem, they say, is developing materials for the equipment that can withstand the high temperatures.

Water spontaneously dissociates at 2,730C (4,946F). This isn't that hard to achieve with a parabolic reflector: it's a matter of size. In the 1700s they ground a 20ft dia glass lens that would instantaneously vaporize stones placed at the focal point. So, I think a mirror about that size is probably what we're talking about to dissociate water by heat.

The hydrogen and oxygen would be lead to a water quench and then separated by gravity. I'm very fond of this idea.

Well the trouble with most 'renewable' energy sources is the fact that efficiency is NOT moot; in fact it is the whole crux of their impracticality.

Ground level solar flux is less than 1KW /m^2 in the very best circumstances. At 100% efficiency, it would take 1000 square meters of solar collector to get one megaWatt.

At the sort of efficiencies of Hydrogen powered cars, that is about enough energy to power one automobile. The cost of that much collector and associated equipment would dwarf the cost of any automobile.

Throw in YOUR tolerance of inefficiency for your solar funrace, and the problem is magnified n times.

If any of these alternative energy schemes were viable they would already be being used. Some are of course in niche markets where they can justify being subsidized by fossil fuel energy.

 

[Seafang]

Didn't they already scrap boranes as rocket fuels back in the sixties because the combustion products are solid and there wasn't much of a way around it?

You end up with borates, which you then have to dispose of, unless there is a new boron fuel that has come out.



Unless we come up with a way to mimic photosynthesis, it takes way more energy to reduce carbon dioxide than it does to split water.

Using methane as an example (from: http://www.webchem.net/notes/how_far/enthalpy/enthalpy_of_combustion.htm )

CH4(g) + 2O2(g) -> CO2(g) + 2H2O(g) DHq = -882 kJ mol-1

That means to go the other direction you need to put in 882 kJ mol-1

Using a fuel cell as the other example (from: http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/electrol.html )

H2(g) + O2(g) -> 2H2O(l) DH = -285.83 kJ mol-1

The opposite reaction would need an input of 285.83 kJ mol-1.

Since the entropy terms would probably be simliar, I'm sure the total free energy change is similar to these also. You get a lot of energy out of hydrocarbons, but to put all that energy back in is just too much for current technology to do cost effectively (I guess). So far, doing it with water to supply the whole world with power is still quite out of reach (I think).

Well if it takes more energy to split CO2 than water, you are saying in effect that carbon is a better source of stored chemical energy than Hydorgen is. But you are still missing my point that a cyclic pprocess that starts with the effluent from an energy consumtion process (burning hydrogen), and then reprocesses that effluent to recover the 'fuel', is a pretty good definition of insanity.

Why not recover the output from a wood fire and reprocess it to recover the wood; think of how many trees that would save; but sadly it would provide us with any net energy. Nor does making hydrogen 'fuel'

 

[Seafang]

Read the links before leaping to conclusions.

I didn't leap to any conclusions; far from it. I merely obseved the laws of thermodynamics. I could read your links and discover that some farmer is consuming the waste from his herd to recover some energy.

Unfortunately he has still not built a fence around his property, and cut the gas and electric utilities off.

 

[Chronos]

A few clarifications

Hydrogen from methanol:

But you are still working with fossil fuels or their derivatives. You still have to dig things out of the ground and "burn" them. This is not a renewable resource.

Methanol can be distilled from wood, a renewable resource. Hydogen can also be obtained from ethanol, which can be distilled from corn - another renewable resource
http://www.cnn.com/2004/TECH/science/02/13/hydrogen.reactors.ap/

Hydrogen from coal:

This is just saying there is a way to extract hydrogen from another fossil fuel that you have to dig out of the ground and burn. It doesn't reduce CO2 emissions, it just saves the hydrogen.

Coal is not 'burned' during gassification, albeit CO2 is still produced. One of the points being made in the linked article on coal gassification was the generator is selling CO2 along with other process byproducts.

Hydrogen from sunlight:

You know all the problems with solar anything. First the sun has to out. Second, the total efficiency is terrible with current technology. You'd have to have solar arrays the size of Kansas to provide enough H2 for the US.

First, no one is suggesting supplying the entire US by this method, it is just another strategy using the free, renewable energy of the sun. Second, in the linked article, the technology uses the heat from sunlight to produce hydrogen. How is that inefficient?

Hydrogen from wind:

Again, the problem is that you need the wind to be blowing. Not everywhere is windy, and you'd need a windfarm the size of Massachusettes to make enough H2 for the US.

Again, no one is suggesting supplying the entire US by this method. While windy locations are an advantage, just about any location will do: deserts, swamps, mountains, wastelands. The productive output may vary with the wind, but the input energy is free and the output

can be stored and used whenever you wish, not just when the wind is blowing.

I didn't leap to any conclusions; far from it. I merely obseved the laws of thermodynamics.

Which is to say you missed the whole point of this discussion. The laws of thermodynamics are not at issue here, and are being met very nicely. All of the processes mentioned require materials and energy to produce hydrogen, which can then be used in place of oil. So what if it takes more energy than you get from burning the hydrogen? If it is free [like the sun or geothermal], who cares?

 

[shrumeo]

A few clarifications

Hydrogen from methanol:Methanol can be distilled from wood, a renewable resource. Hydogen can also be obtained from ethanol, which can be distilled from corn - another renewable resource
http://www.cnn.com/2004/TECH/science/02/13/hydrogen.reactors.ap/

Ah yes, that's why it's called wood alcohol. You'd have to have way more sustainable forests than we have now.

I just remember this seminar where a guy showed how much power the world uses (and the US) and how far short certain renewable resources fall at current levels of technology. He showed that by using biomass, you'd have to use ALL arable land on the Earth to power the US.

Hydrogen from coal:Coal is not 'burned' during gassification, albeit CO2 is still produced. One of the points being made in the linked article on coal gassification was the generator is selling CO2 along with other process byproducts.

I'm sure its pyrolyzed, but I put "burned" in quotes to mean, they heat it and stuff...

Hydrogen from sunlight:First, no one is suggesting supplying the entire US by this method, it is just another strategy using the free, renewable energy of the sun. Second, in the linked article, the technology uses the heat from sunlight to produce hydrogen. How is that inefficient?

In the amount of space it takes up versus the amount of power it produces. And I'm not really even talking about thermal efficiency (car engines are terrible at this too).

Hydrogen from wind:Again, no one is suggesting supplying the entire US by this method.

Then there's little point. We really aren't saving anything by having a few wind farms sparsely placed around the country.

While windy locations are an advantage, just about any location will do: deserts, swamps, mountains, wastelands. The productive output may vary with the wind, but the input energy is free and the output

can be stored and used whenever you wish, not just when the wind is blowing.Which is to say you missed the whole point of this discussion.

At what cost to build, maintain, and operate? If it's not profitable, there won't be much of a line forming to start investing.

The laws of thermodynamics are not at issue here, and are being met very nicely. All of the processes mentioned require materials and energy to produce hydrogen, which can then be used in place of oil. So what if it takes more energy than you get from burning the hydrogen? If it is free [like the sun or geothermal], who cares?

That's great if the input energy is free. It's great that these things produce hydrogen from free energy. But things like wind farms and solar farms aren't going to get out of the niche category unless the cost to produce these things comes down and the watt per dollar to maintain and operate goes up. And again, if they aren't going to supply a major chunk of the power we use then there is little point in bothering.

Things like coal gassification and alcohols from biomass have their own environmental problems to work out and we might as well stick with digging fossil fuels straight out of the ground and putting the carbon into the atmosphere. If we wanted to use this method for any significant chunk of our power "needs" then we'd have to devote almost all our farmland to doing this.

Eh, I googled a few nay-saying webpages:
http://www.recoverybydiscovery.com/hydrogen.htm
http://www.pacificsites.net/~dglaser/h2/General_Articles/
http://evworld.com/view.cfm?section=article&storyid=553&subcookie=1

I think the gist of most of these are "Take an energy source, any energy source, and run your car on it. Then take the same energy source, split water, compress hydrogen, and run your car on it. The hydrogen car goes a tiny fraction that the other car did. Sound stupid? Well, that's the hydrogen economy."

This one tries to dispell the myths of the nay sayers.
http://www.pacificsites.net/~dglaser/h2/General_Articles/E-20HydrogenMyths.pdf
I didn't read the whole thing yet but the first "myth" the dispell is that "A whole hydrogen industry would need to be developed from scratch." and the answer is that we already have lots of hydrogen production infrastructure already in place...we get it from fossil fuels! Myth busted! And they keep talking like they plan to get all their hydrogen from reforming natural gas. Well, not mentioning that the other product of that process is CO2, why not just run the car on natural gas?

 

[Cliff_J]

shrumeo - no one here is naive enough to think we're going to switch to a hydrogen economy overnight and that there aren't challenges to overcome.

But as just one example, currently something like 1/10th of the US electricity generation comes from hydroelectric plants. Anyone could do some math to point out how inefficient it is to have the sun heat up water, condense, collect, and then run through a turbine to make electricity, send over wires and transformers, et cetera.

At some point the cost of pulling up resources from the ground will be higher due to scarcity. Some of us would really like to see those things change well before it gets to that stage.

Its elementary math to think how effective it would be to have "think locally, act globally" take effect inside the US and have people switch to efficient lighting sources alone.

A solar powered car is impractical. But a hydrogen derived from solar energy, energy that is otherwise untilized heating some shingles on a rooftop or sand in a desert. Taking that and making dumb predictions is just as silly as saying we should do nothing. There is plenty of gray area in-between.

Cliff

 

[russ_watters]

The thing I like most about nuclear power is its simplicity. We could research, develop, and deploy a dozen different "alternate energy" schemes in hundreds or thousands of plants that together might account for 20%-30% of our power usage. Or we could build 100 nuclear plants (using existing or only slightly new technology) and replace all of the existing coal plants (50% of our current electric production) and then some.

 

[shrumeo]

Well if it takes more energy to split CO2 than water, you are saying in effect that carbon is a better source of stored chemical energy than Hydorgen is. But you are still missing my point that a cyclic pprocess that starts with the effluent from an energy consumtion process (burning hydrogen), and then reprocesses that effluent to recover the 'fuel', is a pretty good definition of insanity.

Why not recover the output from a wood fire and reprocess it to recover the wood; think of how many trees that would save; but sadly it would provide us with any net energy. Nor does making hydrogen 'fuel'

Oh, I totally agree. I'm in the nay-sayer camp.
I think this "hydrogen economy" stuff is crap.

 

[shrumeo]

shrumeo - no one here is naive enough to think we're going to switch to a hydrogen economy overnight and that there aren't challenges to overcome.

I think there might be a few people who are naive enough to think that it's "right around the corner" or even worth going after at all. I'm not suggesting suspending all research in the matter, but I think people are jumping the gun if they think that any kind of "hydrogen economy" we can drum up any time in the near future is going to reduce pollution or be cost effective.

But as just one example, currently something like 1/10th of the US electricity generation comes from hydroelectric plants. Anyone could do some math to point out how inefficient it is to have the sun heat up water, condense, collect, and then run through a turbine to make electricity, send over wires and transformers, et cetera.

It's not efficient but it's free and practically non-polluting. So it's extremely cash efficient. And actually, any evaluation of the "efficiency" of a natural process like the water cycle wouldn't really apply to anything but the part we care about, the part where the water falls.

At some point the cost of pulling up resources from the ground will be higher due to scarcity. Some of us would really like to see those things change well before it gets to that stage.

That's great. I hope we aren't putting too many eggs in the hygrogen basket.

Its elementary math to think how effective it would be to have "think locally, act globally" take effect inside the US and have people switch to efficient lighting sources alone.

What efficient lighting sources are you talking about?
Lower watt bulbs? Gloomy flourescent lights? That's thinking globally?

A solar powered car is impractical.

Only because current technology isn't good enough. Same problem with the production of hydrogen from renewable resources in a non-polluting way.

But a hydrogen derived from solar energy, energy that is otherwise untilized heating some shingles on a rooftop or sand in a desert. Taking that and making dumb predictions is just as silly as saying we should do nothing. There is plenty of gray area in-between.

Ya lost me somewhere in here.
Did you mean to say that solar power could be used to produce hydrogen gas, then compress it, then put it in a really high pressure tank to drive a fuel cell in a minivan?
How much sunlight would it take?
What area of the Earth would need to be taken up to collect the amount of sunlight needed to produce the hydrogen needed to keep one car running? Multiply that by hundreds of millions of cars.

 

[Chronos]

I perceive a clear difference of opinion here. One party suggests free energy is free, the other party suggests free energy is too expensive.

 

[Cliff_J]

shrumeo - your stance is much clearer now but seems overly pessimistic.

Metal Hydride storage of hydrogen is so safe that even when at full capacity you can crush open a container and extinguish a lit cigarette in the raw fuel storage material. That would be far safer than any petroleum tank.

One website did some elementary math using just off the shelf PV cells with their current efficiency, no future BS, just what could be done today in an Arizona desert. The basis of power production was the current electricity consumption in the US. The size of the thing would be about 125 miles * 125 miles - yes that's millions of acres but would barely be visible from space.

Obviously some carrier would need to store the energy for non-production times and the practicality is bogus because of the enormous cost and energy needed to produce that many cells but that isn't the point. The point is that it wouldn't require covering 110% of the available space on the planet, but instead just a few percent of the desert in one state for a solar electrical farm.

Its a far different matter with transportation if the full potential of the carbon fuels is used as a comparison. But a hydrogen/electric car with primary electric drive from batteries is included its more fair assuming high efficiency is recognised as important too.

Flourescent and LED lights could dramatically cut the needed energy requirements in this country. As could high SEER air conditioners and even motion detection lights that are only on when someone is present or social trends like corporate policies to limit energy consumption. A majority of our electricity comes from coal and natural gas, efforts to help reduce the consumption of those benefits everyone.

There are a few select people making the investment and living off the grid today using PV cells and batteries. There are some making their own biodiesel to drive without using petroleum. Neither is cheaper today and have long ROIs to even come close. But at some point the economies of scale could easily be swayed to the opposite.

I don't think the viewpoints are that different. We both agree the cost is currently too high and as an engineering forum finding means to reduce the cost seems like a worthy discussion.

Cliff

 

[russ_watters]

As I have said before, it is my opinion that this "hydrogen economy" stuff is just misdirected pseud-environmentalism. It does nothing whatsoever to address the primary problem: the generation of electricity. Worse, it is counterproductive because it takes money, effort, and political pressure away from the bigger problem. Until the coal-fired electricity problem is solved, virtually all of our efforts should be directed to it.

Combining the "hydrogen economy" cause with the "alternate energy" cause is even worse: while we waste billions of dollars and decades squeezing another 2% efficiency out of solar cells, building wind farms that produce 50 MW (one skyscraper burns 50MW), we're riding the consumption vs production curve in the wrong direction. In 20 years, with a trillion dollars, we could probably get all that alternate energy up to maybe 20% of our energy production. That's nowhere near enough to be worth it (and certainly not enough to justify any sort of "hydrogen economy" based on it"). Not only is the pollution situation getting worse, but we're in imminent danger of a major power supply crisis. The cascade failure that took down much of the northeastern seaboard last year will be a weekly occurrence and the effect on the economy will be disastrous.

Regarding efficiency gains, yes, they are a good idea and they help, but they aren't a solution. Without a terrible amount of effort or money, you can reduce the energy usage of an older commercial building by 20%. Same goes for your house. But that's not enough to offset the increase in consumption due to economic growth and it doesn't even touch that 50% of our electric power that comes from coal.

And for more, our youngest nuclear plants are more than 20 years old. Even if the irrational anti-nuclear political climate changes (there are hints that it is), it'll be 20 more years before another one comes on-line. In the meantime, a significant fraction of our existing nuclear capacity will be lost. Reaplacing it: more coal and oil. And if this "hydrogen economy" thing happens? Dear god - that'll require doubling the amount of electricity generated by coal and oil. Yeah, altogether, that'll probably result in less oil usage, but it'll mean much more coal.

edit: regarding cars: they are taking care of themselves. I'm sure you've all heard of the new Honda Accord hybrid: 255hp and 37/29mpg. That's a 50% improvement over a typical car of that engine size. Hybrids are the real deal and in 10 years, they'll dominate the auto market.

 

[Averagesupernova]

So we can get hydrogen from ethanol; where do we get the energy to create the ethanol in the first place; current methods of ethanol production take more energy to produce than you get from the ethanol.

Hmmmm. What are you including as the energy needed to make the ethanol? Are you including the energy costs of raising the crop? Because if you are you are fooling yourself. When alcohol is removed from the crop 100% of the food product remains. Absolutely NO nutrition is lost in the process. So are you saying that we should be feeding the grain to livestock without removing the alcohol ahead of time and simply waste it? Contrary to popular belief the production of alcohol is a net gain.

 

[russ_watters]

That's something I know very little about - is alcohol normally removed from grain before the grain is used? How is it done?

 

[Averagesupernova]

That's something I know very little about - is alcohol normally removed from grain before the grain is used? How is it done?

Ummmm, well yes. It can't very well be removed after the animal eats it.

No seriously. I believe they make a mash out of it. Something called distillers grain is often fed to livestock. It is a yellowish white cookie crumb type texture. It is what is left after the alcohol is removed. All of the nutrition an animal would get out of the grain before the process still remains.

 

[hitssquad]

Ethanol vs boron and nuclear gasoline

What are you including as the energy needed to make the ethanol?

Natural gas, coal, and liquid petroleum. Straight from the horse's mouth, one of the ethanol advocacy websites says:
http://www.ethanolrfa.org/factfic_envir.html

energy sources ... such as natural gas and coal ... convert grain into a premium liquid fuel. ...17% of the energy used to produce ethanol comes from liquid fuels, such as gasoline and diesel fuel.

When alcohol is removed from the crop 100% of the food product remains.

It does not. Alcohol is formed from the carbohydrates in the grain. There is a net loss in this conversion. It takes fossil-fuel energy to grow the crop, and it takes fossil-fuel energy to distill the carbohydrates in that crop into ethanol. If we as Americans stop using ethanol in our cars, and continue to drive the same amount of miles, we will see a net savings in our fossil fuel consumption.

You cannot replace liquid fossil-fuels with ethanol. You can replace them with boron; and you can replace them with http://www.archive-one.com/new-5453663-4277.html . If ethanol could replace liquid fossil-fuels, Nazi Germany might not have felt the need to develop the Fischer-Tropsch process:

The Fischer-Tropsch process, named after its developers, the German chemists Franz Fischer and Hans Tropsch, was used extensively in Germany in the 1930s to produce synthetic petroleum and diesel fuel. It uses a mixture of carbon monoxide and hydrogen gases with a catalyst containing nickel, cobalt, or modified iron. The process is currently used to produce the raw materials for manufacturing synthetic fats and soaps.

Microsoft® Encarta® Encyclopedia 2002. © 1993-2001 Microsoft Corporation. All rights reserved.


Except for the biomass-fermentation process, liquid fuel synthesis has changed little since the process was first developed in Germany during the 1930s. This first technique, called the Fischer-Tropsch process, used steam and oxygen to produce coal gas, which was then liquefied by a catalytic reaction. The Fischer-Tropsch process was used to manufacture nearly 600,000 metric tons of synthetic coal fuels each year during World War II (1939-1945).

Microsoft® Encarta® Encyclopedia 2002. © 1993-2001 Microsoft Corporation. All rights reserved.

 

[Averagesupernova]

Natural gas, coal, and liquid petroleum. Straight from the horse's mouth, one of the ethanol advocacy websites says:
http://www.ethanolrfa.org/factfic_envir.html




It does not. Alcohol is formed from the carbohydrates in the grain. There is a net loss in this conversion. It takes fossil-fuel energy to grow the crop, and it takes fossil-fuel energy to distill the carbohydrates in that crop into ethanol. If we as Americans stop using ethanol in our cars, and continue to drive the same amount of miles, we will see a net savings in our fossil fuel consumption.

You cannot replace liquid fossil-fuels with ethanol. You can replace them with boron; and you can replace them with http://www.archive-one.com/new-5453663-4277.html . If ethanol could replace liquid fossil-fuels, Nazi Germany might not have felt the need to develop the Fischer-Tropsch process:

Maybe you should quote the whole paragraph?

Doesn't it take more energy to produce ethanol than you get from it?

No. Whether produced from corn or other biomass feedstocks, ethanol generates more energy than used during production. Plants used in ethanol production harness the power of the sun to grow. By releasing the energy stored in corn and other feedstocks, ethanol production utilizes solar energy, replacing fossil energy use. A life cycle analysis of ethanol production - from the field to the vehicle - found that ethanol has a large and growing positive fossil energy balance. According to a 2002 U.S. Department of Agriculture study, ethanol yields 34% more fossil energy than is used to grow and harvest the grain and process it into ethanol. The study makes note of significant energy efficiency improvements that have been made in ethanol production due to higher yielding corn varieties, technological advances in ethanol production such as the use of molecular sieves and natural gas, and improved farming practices (precision and no-till farming.)

Unlike ethanol, other fuels, including MTBE and gasoline, take more fossil energy to produce than they yield.

Importantly, producing ethanol from domestic grains achieves a net gain in a more desirable form of energy. It utilizes abundant domestic energy sources, such as natural gas and coal, to convert grain into a premium liquid fuel. Only about 17% of the energy used to produce ethanol comes from liquid fuels, such as gasoline and diesel fuel.

 

[russ_watters]

Ummmm, well yes. It can't very well be removed after the animal eats it.

No seriously. I believe they make a mash out of it. Something called distillers grain is often fed to livestock. It is a yellowish white cookie crumb type texture. It is what is left after the alcohol is removed. All of the nutrition an animal would get out of the grain before the process still remains.

I just didn't think they did anything like that before they made bread, for example. And since there is nutritional value in alcohol (its a carbohydrate) it doesn't seem right that "all of the nutrition" is still there.

What you are saying seems highly misleading. Another thing:

Unlike ethanol, other fuels, including MTBE and gasoline, take more fossil energy to produce than they yield.

This is rediculous. If it took 2 gallons of gas (for example) to get a gallon of gas to your car, it wouldn't be worth using.

 

[Chronos]

Ouch, this all seems misinformed. Ethanol from plants [e.g., corn] is condensed solar energy. Corn gets it's energy from the sun and so do the bacteria that convert corn sugar to ethanol. The waste product still retains the starch [carbohydrate] energy, but not the sugar. The loss is, however, rather minimal and the ethanol is essentially free. Ethanol, however, can be used directly as fuel [it already is]. No need to convert it to hydrogen.

 

[hitssquad]

Fuel energy-yield vs total per-unit fossil-energy input

According to a 2002 U.S. Department of Agriculture study, ethanol yields 34% more fossil energy than is used to grow and harvest the grain and process it into ethanol.

Ethanol may have a positive energy yield, but if it does it is because of input from solar energy. Solar energy is relatively diffuse which contributes to its being environmentally-destructive, dangerous and expensive.

Ethanol's positive energy yield is not mutually-exclusive with the possibility that it takes more fossil energy to produce than do fossil fuels:
http://www.free-eco.org/articleDisplay.php?id=21

• A study last year by Cornell University scientist David Pimentel highlighted another problem. Most replacements for gas--including ethanol--have to be manufactured. It turns out this process is both energy-intensive and expensive. Pimentel's analysis showed that it takes about 70 percent more energy to produce ethanol than the resultant ethanol yields. The additional energy comes from, you guessed it, fossil fuels.
  
  Pimentel found it costs $1.74 to produce a gallon of ethanol, twice that for gasoline. He notes that's why "fossil fuels--not ethanol--are used to produce ethanol... Growers and processors can't afford to burn ethanol to make ethanol."

Perhaps the USDA study was only counting fossil-energy used onsite and not also the fossil-energy used to produce the fossil-energy used onsite.

 

[hitssquad]

Fossil fuel input in modern agriculture

Corn gets it's energy from the sun and so do the bacteria that convert corn sugar to ethanol. The waste product still retains the starch [carbohydrate] energy, but not the sugar.

Modern agriculture has a sizeable petroleum input. This is why, depending on one's diet, it is possible to get better gas mileage driving an average car than riding a bike.

ethanol is essentially free.

Ethanol is so expensive that...
http://www.free-eco.org/articleDisplay.php?id=21

• "...Growers and processors can't afford to burn ethanol to make ethanol."
  
  Unfortunately, taxpayers will make up the difference in the form of subsidies and higher fuel prices of 4 to 10 cents per gallon. Further, since ethanol can't be sent through pipelines, transportation costs will make it even costlier on the East and West coasts.
  
  There are huge payoffs for finding the "miracle fuel" (i.e., one that is both clean and cheap). As yet, no one, nowhere has found it.

 

[Averagesupernova]

Hitsquad, I really don't know how to reply to some of the things you have posted. Apparently I haven't been clear enough to make you understand my viewpoint. Corn is, has been, and will continue to be grown regardless of ethanol use. The energy used to produce the crop that alcohol plants use will continue to be used to grow the crop because it is used in so many other places. As I said before after the alcohol is removed from the grain it is still suitable for livestock feed as well as many other things. So the alcohol can be considered a by-product. The alcohol plants don't consider it a by-product, but most people don't consider gasoline a by-product either. Guess what? Before cars were around it WAS considered a by-product because there was little use for it. But people didn't say to scrap the idea of using gasoline (well maybe they did, none of us were alive then to remember) to fuel vehicles because it adds another process to refinement which in turn takes more energy.

Your comments about solar energy: So your suggestion is to quit growing food? Once again, the crops will be raised because 1) it is profitable, 2) we need to eat, 3) a host of other reasons we could come up with. Fuel WILL go into producing the crop regardless of whether or not alcohol is harvested from it.

I read some from the link you posted. Here is a quote:

Pimentel found it costs $1.74 to produce a gallon of ethanol, twice that for
gasoline. He notes that's why "fossil fuels--not ethanol--are used to produce ethanol... Growers and processors can't afford to burn ethanol to make ethanol."

Once again, I ask how did they arrive at this? You CANNOT use the energy used to grow the crop because it will be grown regardless.

The reason why growers cannot afford to burn ethanol to make ethanol is because using ethanol requires gasoline. Tractors that burn gasoline are cost prohibitive to run regardless of whether or not the gasoline contains ethanol. Requiring producers to use ethanol is tantamount to require any vehicles at an electric power generating plant to run on electricity.

Russ, you think it seems rediculous that it takes more energy to produce a gallon of gas than what that gallon of gas will yield. I don't claim to know for sure if this is true. But what is the alternative? No more gas? There is still a net gain over not doing it at all.