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THE Hydrogen Thread pt 3 (merged)

Discussions of conventional and alternative energy production technologies.

Its all about hydrogen.....

Postby rerere » Tue 24 Aug 2004, 09:15:00

Hydrogen mobility is what makes batteries work. But hydrogen gas is a poor energy storage device. The reason it gets consideration is because Water and the way to make hydrogen is well known and technologically simple to make gas from.

Before I visited Don Lancaster http://www.tinaja.com/h2gas01.asp I was looking into what it would take to store energy with Hydrogen gas. Now, I think Vanadium Redox http://www.ceic.unsw.edu.au/centers/vrb/ looks to be the best way to 'store' excess power. Now, All I need it the land to harvest the power.....
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Postby rowante » Wed 25 Aug 2004, 09:03:38

Very interesting pro-hydrogen article claiming to debunk 20 hydrogen myths...

http://tinyurl.com/4cw8x (PDF Download.)

This article should put the cat amongst the pidgeons.
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Postby Devil » Wed 25 Aug 2004, 10:42:48

$this->bbcode_second_pass_quote('rowante', 'V')ery interesting pro-hydrogen article claiming to debunk 20 hydrogen myths...

http://tinyurl.com/4cw8x (PDF Download.)

This article should put the cat amongst the pidgeons.


I have only quickly skimmed through the link (don't have time to read all 49 pp in detail!). It is extremely adroitly written, not hesitating to further half-truths and to quote extremes, especially with figures, where it suits their arguments. However, it smacks more of the kind of arguments proposed by lawyers into bamboozling a jury into acquitting their clients than something that would stand up to scientific scrutiny. Notwithstanding, they propose CH4 as the source of hydrogen but talk fine talk about the resultant CO2, but propose no solution.

IF, and it's a very big IF, hydrogen were to be used en masse, then using fossil methane is not, nor ever will be, a viable option.

I can't discuss the points individually, but even a casual reading has revealed many contradictions within the article. This would possibly have been more convincing if it were not obvious that it was written with vested interests in mind.

As I say, cleverly argued, but not very convincing, for me.
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Postby rowante » Fri 27 Aug 2004, 03:20:16

Devil, what I found most interesting was the information on the efficiencies of fuel cells compared to ICEs. I don't think this is known or understood by most people on this forum.

I think you should take the time to re-read the article in detail, I get the feeling your opinion was hastily drawn. Without addressing the points how can what you say be taken seriously? What contradictions? etc.

I actually think there is much more vested interest against hydrogen/hydrogen carriers... when one looks at the money invested in the current energy infrastructure it makes me suspicious. If it really was as hopeless as claimed why would virtually all major car companies etc be researching and investing billions in this technology?

I find many people (not necessarily you) throw around figures about EROEI etc when they have researched only one side of the story. I know I have been guilty of said in the past. Unless you are a scientist or expert working in this field how can you be so sure of yourself?

$this->bbcode_second_pass_quote('', ' ') Myth #11. Manufacturing enough hydrogen to run a car fleet is a gargantuan and hugely expensive task.

If all current global production of industrial hydrogen, about 50 million T/y, were fed into light vehicles about as efficient as the Revolution fuel-cell concept car described above (i.e., quintupled-efficiency or “5?” for short), it would displace two-thirds of today’s entire worldwide consumption of gasoline. 101 An estimated one-third of that hydrogen production is currently being used to make gasoline and diesel fuel; 102 the rest makes non-petroleum products. In the U.S., about half of all hydrogen is used by refineries, but highway-fuel consumption is also higher, so diverting all refinery consumption of hydrogen (~7 MT/y) into direct fuel for 5? light and 2? heavy vehicles would displace one-fourth of the gasoline (twice as much as comes from Persian Gulf oil), or one-seventh of the gasoline plus diesel fuel, used by all U.S. highway vehicles. 103 While making enough hydrogen to displace all U.S. highway vehicles’ fuel is a significant undertaking, it looks reasonable in size and cost: it’s comparable to the world’s current total hydrogen production of ~50 MT/y, and just North and South Dakota have enough cost-effective windpower potential to make that much hydrogen. 104 (Byproduct oxygen could valuably gasify dry biomass or coal to make even more hydrogen.) Nor is the conventional hydrogen industry standing still: world hydrogen production is growing about 6% per year (particularly to help desulfurize diesel fuel), corresponding to a doubling every 11 years. Having fuel-cell car usage grow fast enough to outrun a hydrogen industry that’s capable of such massive, but routine and invisible, expansion is a problem we’d love to have.
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Postby The_Virginian » Fri 27 Aug 2004, 04:27:41

Look at "Myth #4".

In it they chastize the "swiss scientists" for daring to mention that Electrolysis is in-efficient.

So instead he no so subtly suggests that the Hydrogen fuel of tommorow will be made wtih FOSSIL FUELS. (OIL/GAS)..no in fact he comes out ans says it.


What the "Heck" ????:evil:

So all that great "energy efficiency" of the fuel cell can be lost in conversion, just so we can continue on our path to "Peak Oil"?

What a sham.

Truth #1 : Hydrogen will not replace OIL/GAS if we need it to make Hydrogen.
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Postby Devil » Fri 27 Aug 2004, 06:29:27

$this->bbcode_second_pass_quote('rowante', 'D')evil, what I found most interesting was the information on the efficiencies of fuel cells compared to ICEs. I don't think this is known or understood by most people on this forum.

I think you should take the time to re-read the article in detail, I get the feeling your opinion was hastily drawn. Without addressing the points how can what you say be taken seriously? What contradictions? etc.

I actually think there is much more vested interest against hydrogen/hydrogen carriers... when one looks at the money invested in the current energy infrastructure it makes me suspicious. If it really was as hopeless as claimed why would virtually all major car companies etc be researching and investing billions in this technology?

I find many people (not necessarily you) throw around figures about EROEI etc when they have researched only one side of the story. I know I have been guilty of said in the past. Unless you are a scientist or expert working in this field how can you be so sure of yourself?

$this->bbcode_second_pass_quote('', ' ') Myth #11. Manufacturing enough hydrogen to run a car fleet is a gargantuan and hugely expensive task.

If all current global production of industrial hydrogen, about 50 million T/y, were fed into light vehicles about as efficient as the Revolution fuel-cell concept car described above (i.e., quintupled-efficiency or “5?” for short), it would displace two-thirds of today’s entire worldwide consumption of gasoline. 101 An estimated one-third of that hydrogen production is currently being used to make gasoline and diesel fuel; 102 the rest makes non-petroleum products. In the U.S., about half of all hydrogen is used by refineries, but highway-fuel consumption is also higher, so diverting all refinery consumption of hydrogen (~7 MT/y) into direct fuel for 5? light and 2? heavy vehicles would displace one-fourth of the gasoline (twice as much as comes from Persian Gulf oil), or one-seventh of the gasoline plus diesel fuel, used by all U.S. highway vehicles. 103 While making enough hydrogen to displace all U.S. highway vehicles’ fuel is a significant undertaking, it looks reasonable in size and cost: it’s comparable to the world’s current total hydrogen production of ~50 MT/y, and just North and South Dakota have enough cost-effective windpower potential to make that much hydrogen. 104 (Byproduct oxygen could valuably gasify dry biomass or coal to make even more hydrogen.) Nor is the conventional hydrogen industry standing still: world hydrogen production is growing about 6% per year (particularly to help desulfurize diesel fuel), corresponding to a doubling every 11 years. Having fuel-cell car usage grow fast enough to outrun a hydrogen industry that’s capable of such massive, but routine and invisible, expansion is a problem we’d love to have.


I'm sorry, I've not got the time, as I said, to refute 49 pp of half truths and utter codswallop, no matter how well written. I'll just ask one question: what are they going to do with all the CO2 they will generate along with the H2 (they even propose to oxidise coal with electrolytic oxygen. concomitant with hydrogen production)? This is a pro-climate-change document written by pro-fossil fuel activists (read the oil, coal and gas lobbies), with the author himself actually declaring his own vested interest.
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Postby Agren » Mon 30 Aug 2004, 07:32:19

$this->bbcode_second_pass_quote('', ' ')I'll just ask one question: what are they going to do with all the CO2 they will generate along with the H2


They do pose some answers to that question, and I belive what they say has some merit.

After reading about 2/3 of the article (I'll finish it eventually) I would say that a lot of what they say makes lots of sense, but is irrelevant. The conclusions are probably reasonable, given the assumptions.

However, one of the most basic assumptions are made in Myth #12:
$this->bbcode_second_pass_quote('', 'N')atural gas is at least a 200-year global resource


So, as noted before, basically they are saying that we should convert Nat.gas to hydrogen and then run our cars on that. I have yet to find any proof for the claim about 200 years of nat.gas in the world

However, they do make some interesting points on the efficiency on H2 engines, basically saying that even though we lose energy in the conversion from NG to H2 that is more than made up for by getting better efficiency in the engine.

If I find anything else I'll get back on the subject
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Postby Guest » Mon 30 Aug 2004, 07:56:02

It may be that we have 200 years of NG at the present rate of consumption but, if we start using it for everything, how many years will we have? 20, 30?

There is still an unanswered question: CO2. No matter how we handle NG, for every molecule of methane we use, no matter how, one molecule of CO2 will be emitted, sooner or later. That means for every kg of NG, there will be 2.75 kg of CO2 emitted, whether it be burnt or converted to hydrogen. This is a big no-no. And the faster we use it, the bigger the no-no. We should be looking to cut down NG consumption, not increase it.
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Postby Devil » Mon 30 Aug 2004, 07:59:15

Sorry, the last message was mine. I sent it from a different 'puter than usual and forgot to log in. My bad :(
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Postby Agren » Mon 30 Aug 2004, 08:00:52

As i said, they do present some solutions to he CO2, I don't have time right now to dig up what they say, but it sounded at least somewhat reasonable to me when I read it. But then again, since I highly doubt the 200 years I might have brushed off the CO2 issues.
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Amory Lovins & H2

Postby EnviroEngr » Sun 19 Sep 2004, 23:11:33

RMI's newest hydrogen publication, T04-06–"Comment on the American Physical Society Hydrogen Report," discusses the American Physical Society's (APS) echo of basic errors in National Academy of Sciences and other recent reports about the alleged obstacles to a hydrogen economy. These errors elicited a correction in the July 2004 Physics and Society from APS member Amory Lovins, focusing on hydrogen storage, cost, and transition strategy.

Comment on APS Hydrogen Report

See also:
RMI's Publication Page
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Postby backstop » Mon 20 Sep 2004, 01:11:28

The hype for hydrogen began, as far as I saw, with senior reps of the oil industry talking of it as the clean fuel of the future, and with others talking of how it can be made with renewable energy.

Most of fred public have yet to twig the con (exemplified in BP : Beyond Petroleum) by which we're meant to feel better about oil companies because, after all, they have to make profits to develop the hydrogen future.

Furthermore, most are still ignorant of the fact that the vast majority of hydrogen would be made from fossil fuels for the foreseeable future, and that this would of course raise the net GHG output per mile of vehicle travel.

Very few are aware of a further problem with this scam: the opportunity cost of using renewables to electolyze hydrogen. Sadly, short of an utter collapse, it's likely to be many years before sufficient renewable energy is on line to exceed baseload power demand (i.e. 3am summer) at least in industrialized nations.

Once we're beyond that point, using a surplus of renewable power to electolyze hydrogen for compression, storage, transport, re-storage, and sale, may or may not make sense under that distant year's priorities.

Up to that date every unit of renewable power used to make hydrogen to displace petrol will mean an extra unit of coal-fired electrictity being made, with its increased GHG output per unit of energy.

Given the annually rising profile of Climate Destabilization, e.g. Blair is chairing the next G8 and has declared that the climate issue will be its first priority, and given that only 12% of new vehicles being HF-Cs by 2020 is being quoted, the opportunity cost of Renewable Power > Hydrogen look to me like the final straw that makes it a non-starter.

Item : The villagers of Hornchurch in Essex, UK, have refused to have a Hygrogen filling station anywhere near their homes, meaning tankers now arrive to fuel some experimental HF-C busses. Score 1 Fred Public.

However, while pure Hydrogen is a piss-poor energy carrier for various reasons that other posts have addressed, and has no prospect of benign production in the foreseeable future, it's not the only option for fuel cells and I hope the critique of it in this thread won't be assumed to spread to them by association.

If I knew the web address I'd now write it, but as it is I must write that there are posts on Energy Tech Forum, "Would Electric Vehicles really be so bad"; page 3, which address the option of producing Methanol for use in fuel cell vehicles from Coppice Woodland.

This seems to me the one highly sustainable fuel production option, with wide global replicability, by which we may see fuel cell vehicles catching on and reducing dependence on fossil liquid transport fuels.

To this end, if anyone gets to hear of some bright spark in a shed/garage/uni engineering shop having a go at a really basic Methanol fuel cell vehicle, could they please post the info ?

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A.E. company---anybody?

Postby parainwater » Thu 28 Oct 2004, 05:24:37

I am new to this forum but have definately kept abreast of the impending energy crisis. I am a registered professional mechanical engineer and know quite alot about alternate energy; particulary active and passive solar, saline gradient solar ponds, wind energy, biomass and micro-scale hydroelectric. I am currently designing several power generating and electrolytic hydrogen production systems that use highly ubiquitous materials (Home Depot primarily) in order to keep the costs acceptable. I believe it is possible for many people to become more, if not totally energy independent in an affordable manner. However, I was laid off from my job at White Sands Missile Range 18 months ago and I am dirt poor and do not have the resources to help people with their energy needs. I would like to hook up with some people who would like to start an alternate energy company that provides plans, kits, systems and energy consultation. I believe we will soon see a cornucopia of alternate energy companies pop up like the dot-coms of the 90's. I also believe that the bulk of these companies will be out to sell snake oil to desperate people in order to make a quick buck. I would like to establish a company that quickly gains a reputation of delivering systems that meet or exceed stated perfomace energy output and at affordable prices. I live in southern New Mexico and we are abundantly blessed with sunshine and wind. Anyone with a serious interest in this idea would be greatly appreciated.
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Re: A.E. company---anybody?

Postby rerere » Thu 28 Oct 2004, 11:19:45

$this->bbcode_second_pass_quote('parainwater', 'e')lectrolytic hydrogen production systems that use highly ubiquitous materials (Home Depot primarily)


'electrolytic hydrogen production '

meaning you are gonna make hydrogen by splitting water?

When did Home Depot start selling power supplies? What material from Home Depot can contain Hydrogen? What materials from Home Depot will purify Hydrogen?

$this->bbcode_second_pass_quote('parainwater', ' ')Anyone with a serious interest in this idea would be greatly appreciated.


There is always interest in a way to lower the energy required to break about water to get Hygrogen.
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A.E. company #2

Postby parainwater » Thu 28 Oct 2004, 14:53:36

Splitting hydrogen from water via a d.c. current is very simple. By adding the apropriate amount of sulfuric acid H2SO4 to clean water (distilled is best by no means necessary), H2 is liberated at the cathode which can be made of stainless steel and oxygen at the graphite anode. With properly designed PVC cells a 75% conversion efficiency is very attainable. I have designed a method to manufacture (pyrolize) graphite anodes from ordinary charcoal briquets at very low cost. As for the power supply (no--Home Depot does not cell electrolytic power supplies). That would be counterproductive any way as most power supplies are powered by a fossil fuel burning power plant. The idea is to generate electric power above your required household needs and divert the extra power to a bank of electrolytic cells. A simple circuit of SCR's will engage and disengage the proper amount of cells in accordance with the variable voltage output of say a Rankine cycle steam engine powered by a parabolic solar concentrator or wind turbine. I have also designed a simple way to modify a run-of-the-mill Briggs and Stratton or Tecumseh lawnmover engine to operate as a Rankine sycle steam engine. You can also reduce the cylinder head volume to optimize the steam expansion ratio in accordance with the boiler pressure located at the focus of the parabolic concentrator. After I build the first concentrator I will then take a mold of the dish and use a fiberglass chopper gun to mass produce the dishes. As for storing the hydrogen gas there are generally three methods employed. Compressed hydrogen, cryogenic hydrogen and hydrogen stored in a particulate metal "mol sieve". The first two methods are highly energy intensive to compress or liquify hydrogen. However, I submit to you that there is another option. Now here me out before you form a judgement on this idea. If one were to construct a cylindrical mylar bag of say 10 ft in diameter by 30 ft long, you would have a storage volume of length*(pi/4)*diam^2 cubic feet. So for these dimensions that works out to 2356 ft^3. At STP conditions hydrogen is an ideal gas and therefore the mass of hydrogen in this bag would be m=(PV/RT)*Mw. So if your local atmospheric pressure is 14psia and an ambient temperature of say 80F, the bag would contain 5.69 lbmol of H2 or 11.4 lbm of hydrogen gas. H2 has a thermal energy content of around 62,000 BTU/lbm. A gallon of gasoline has a thermal energy content of around 124,000 BTU/gal. So therefore this mylar bag would contain the gasoline equivalent of 5.7 gallons. An off the shelf gasoline powered generator can easily be modified to run on the hydrogen during the night or on a cloudy day. The neat thing about this approach is that your varying household electric demand is totally independent of power decay(availability). As long as there is hydrogen in the bag you can produce steady or variable houshold power. Where as a battery bank will of course loose its charge and hence the available power to your home will drop during the night. But isn't H2 highly explosive? It is only explosive when mixed with the proper amount of oxidizer(oxygen in the air). As long as the air is excluded from the mylar bag there is no explosion hazard. Flammability hazard--yes. By placing the bag in a properly grounded sheet metal enclosure, this hazard is greatly reduced if not eliminated. Of course gross neglegence is a factor. I wouldn't smoke,weld or work on the bag unless it was vented down and my body was physically grounded. This idea is not a panacea solution for everyone. Obviously if you live in a closely spaced suburb it would not be practical. However, people who have a minimum of about .5 acre or so of land could implement this system. I live on 1 1/4 acres and am going to build not only the solar concentrator but a wind turbine, active solar heating system and a heat driven ammonia absorbtion refrigeration system for my home---if I ever get a job.
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AE company

Postby Optimist » Thu 28 Oct 2004, 16:59:39

Let's talk about serious for a moment. You claim $this->bbcode_second_pass_quote('', 'W')ith properly designed PVC cells a 75% conversion efficiency is very attainable.
The numbers I have seen are more in the 30 - 35% range. You are talking more than double that. Do you have a reference to back up that claim?

Your mylar bag (assuming it works as claimed) will contain ~705, 000 BTU or 745,000 kJ. Let's assume that you had 8 hours of intense sunlight (1 kW/m^2) at your disposal per day, in NM. So sunlight hitting the ground is 1 x 8 X 3600 = 28,800 kJ/m^2. Your solar collector has an efficiency of what? 20%? So you end up with .2 x 28,800 = 5,760 kJ/m^2 electrical energy. Your conversion to hydrogen also loose some energy. Using the disputed 75% efficiency your hydrogen energy yield is .75 x 5,760 = 4,320 kJ/m^2. Bottom line, to fill the bag you will need a collector area of 745,000/4,320 = 172 m^2! Almost 2 football fields! If the electrolysis is 35% efficient, instead of 75% efficient you end up with a whopping 370 m^2!

Do you have a budget cost estimate on 370 m^2 of solar collector area? I suspect few households would be rushing in to make that investment.
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Postby big_rc » Thu 28 Oct 2004, 17:12:26

Quick question my man.

Mylar is a polyester meaning it is going to have a finite hydrogen and oxygen permeability. That means your big bag is going to be constantly loosing hydrogen. Have you done the calculations to see what percentage of the hydrogen you produce will be lost due to H2 diffusion our of the bag? Also if enough air/O2 gets into the bag you have a pretty interesting situation now.
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Cost

Postby Optimist » Thu 28 Oct 2004, 17:31:35

According to http://www.peakoil.com/fortopic2542.html (see the second post) an electrical solar collector costs $660 for 150W. For the collector in question you need 745,000 kJ/ 8 h sunlight a day/ 3600 s/h = 25.9 kW or 25,900 W. Ignoring benefits of scale, this would cost $660/150 x 25,900 = $114,000, just for the solar collectors.

Good luck selling that...
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Postby johnmarkos » Sat 04 Dec 2004, 19:32:45

What if we think of hydrogen as a battery rather than as a fuel? That is, if a hydrogen fuel cell is a battery, is it an efficient battery or an inefficient one? How does producing hydrogen by electrolysis compare to other methods of storing electrical energy in batteries?

I was glancing over Jeremy Rifkin's "The Hydrogen Economy" today and it occurred to me that the above point might be what he's getting at. I mean, Rifkin wrote the book on Entropy (literally) so he's not likely to be confused into thinking that hydrogen is an actual energy source. What is the reason for his enthusiasm about it?
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Postby johnmarkos » Thu 27 Jan 2005, 12:16:53

$this->bbcode_second_pass_quote('johnmarkos', 'W')hat if we think of hydrogen as a battery rather than as a fuel? That is, if a hydrogen fuel cell is a battery, is it an efficient battery or an inefficient one? How does producing hydrogen by electrolysis compare to other methods of storing electrical energy in batteries?

I saw a panel discussion with Richard Heinberg last night. He informed us that he had just visited one of the most advanced hydrogen research facilities in the country. The engineers told him that as an energy storage mechanism, hydrogen is currently less effective than traditional battery technology.

So that's it: the final nail in the coffin of the hydrogen economy. Hydrogen is not an energy source, nor is it an effective battery. Society should invest elsewhere.
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