posted
People always say "it's coming, it will be here soon, it's just around the corner, any time now..."
...and then nothing happens, and we carry on burning gasoline and using Windows (well, except for me, but I'm just better than you are).
I think that the hydrogen economy, like Linux on the desktop, is in fact not coming. I do not believe that the world will one day run on hydrogen. I feel this way because there are presently only two practical ways of making hydrogen: reforming and electrolysis. Reforming is a waste of perfectly good ethanol, and electrolysis is kind of silly, because you're breaking water down to make hydrogen and oxygen and then turning around and recombining them to make water again... but the electrolytic process requires more energy than the fuel cell generates.
"But what about using solar cells to power electrolysis?" you ask... well, solar cells are woefully inefficient, not to mention that their creation requires all sorts of nasty heavy metals. And they aren't presently all that long-lived. Also, they occupy valuable land space.
There is only one alternative energy source that I consider to be really viable -- sea-based wind farms. Those, though, can only blunt our need for energy, not solve the problem. In fact, there isn't really a single solution to the energy problem. And really, if you're building sea-based wind farms, why not just use the electric power directly rather than bothering with wasting energy to convert it to hydrogen when you won't even get as much back as you put in?
There's also nuclear power. I like nuclear power in some senses, but I want to wait and see what happens with the cancer rates among longtime (25+ years) nuclear plant operators when they retire. I don't trust humans to handle nuclear power properly -- every accident or near miss that has ever occured at a nuclear power plant to my knowledge has been the direct result of human error or human stupidity. So I tend to take a "we're to dumb to use it wisely, but I'd like to see it in use" approach to nuclear power. That goes double for waste disposal; Mount Yucca is one of the stupidest ideas ever concieved. Deep-seabed burial is cheaper (uses existing drilling technology) and much less dumb as far as protecting living things from radioactivity is concerned.
OK, so I've been ranting a bit. I just had to do my fourth year design project for a fuel cell group -- my project was in control systems -- and I'm really sick of hearing about the hydrogen economy. Oh, and I'm also sick of hearing about Linux on the desktop. Posts: 10886 | Registered: Feb 2000
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posted
"And really, if you're building sea-based wind farms, why not just use the electric power directly rather than bothering with wasting energy to convert it to hydrogen when you won't even get as much back as you put in?"
posted
Used batteries are waste -- and if they're rechargeable, usually fairly toxic. "Used" hydrogen is water. Posts: 32919 | Registered: Mar 2003
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posted
Fuel cells are extremely efficient as well as light, a good fuel cell battery has the potential to store more energy than any lithium-ion or anything else, without the memory too. Satyagraha
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posted
Not the average, at least not yet, but its making steady progress on the corporate desktop, even the typical luser's. The ones who don't need to know how to install anything in the first place.
Posts: 15770 | Registered: Dec 2001
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posted
The hydrogen economy may be more like a nuclear airplane. An interesting idea but trying to merge two things that are inherently incompatible as a matter of scale. (And yes the U.S. government wasted gazillions of dollars because beuracrats couldn't figure out that they were inherently incompatible)
Allow me to ramble about nuclear applications for a moment, I swear I will come to a point with hydrogen. The reason why we have nuclear powered ships, but not nuclear powered cars is an interesting exploration into the development of the public mindset and technological innovation. The reason why it works well on larger boats (aircraft carriers, nuclear submarines) is because they can accomodate the space to weight tradeoff for a reactor pile and because they have an unlimited cooling supply via seawater even if the sea water only contacts the cooling reactor water via heat exchangers. This space to weight trade off is why you can't put an actual nuclear reactor pile in a plane, or even in a car. The only way a car or plane would be fueled by a nuclear reactor is indirectly. And with any airplane, you don't have the space to weight ratio to actually accommodate the sort of batteries necessary for straight electricity storage.
Now, after 3-mile island and chernobyl people recoil with horror at the idea of putting nuclear reactors in planes or cars. But it wasn't too long ago that the "Nuclear Age" was going to do everything AND make children eat their vegetables.
Now at the begining of the nuclear heyday 50s and 60s if you had asked people about hydrogen power, they would have recoiled in horror. Do you know why? Because the Hindenburg disaster was still fresh in the collective national memory. If you had asked them which was more dangerous they probably would have said hydrogen over nuclear power.
It is all about perceptions, not reality.
(ok taking a break in my diatribe and coming back after I run the dogs)
Posts: 11265 | Registered: Mar 2002
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posted
Ah, well I do all my surfing, geneology, writing, email and so forth using linux and I am by no means a computer whizz.
Posts: 2022 | Registered: Mar 2004
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(think I'm going to postpone the other half of this till tomorrow, twinky feel free to IM me at BannaOj or e-mail me to remind me to finish this)
...or lack thereof. There is no distribution infrastructure for hydrogen the way there is for petroleum products, and building such infrastructure would be a massively expensive undertaking. Storing hydrogen is also inconvenient -- even handling small tanks of it, like the ones commonly used in laboratories, requires extreme care.
There is also the matter of water vapour being a greenhouse gas, just like carbon dioxide. That's another problem fuel cells can't solve.
AJ, I await your post tomorrow. Posts: 10886 | Registered: Feb 2000
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posted
It's worth noting that the Hindenburg explosion has recently been proven to NOT have been caused by the hydrogen (although it surely fueled the blaze once it got going) but by the combination of a highly flammable coating and uneven dispersal of electric charge. Linky
As far as hydrogen delivery goes, one word: zeolites.
Posts: 32919 | Registered: Mar 2003
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posted
I have serious doubts about solid state storage of hydrogen. The zeolite idea is just like the nanotube storage idea. Good on paper, but difficult and problematic to do in real life. (not to mention that the worlds largest zeolite manufacturer is ExxonMobile. 'nuf said.)
I've always liked the idea of themal electricity production. Some of the new semiconductors have a pretty decent efficiency rating. Good enough the navy is looking at using them on ships rather than generators.
Posts: 1621 | Registered: Oct 2001
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posted
Rivka, zeolites do not solve the distribution problem. Hydrogen still has to be transported from wherever it is produced to wherever it is to be consumed -- be that in a pipeline or in a bunch of zeolites loaded into a truck.
Posts: 10886 | Registered: Feb 2000
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posted
Twinky, given that the petroleum distribution network will not suffice within our lifetimes, is it your opinion that we should be looking at PURELY electric vehicles instead of developing a distribution network for a more efficient fuel? If so, how do you address the fact that we've yet to develop one that's remotely practical?
Posts: 37449 | Registered: May 1999
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posted
It isn't a more efficient fuel. It's much more intensive -- and expensive -- to produce and distribute. Sure, there's no remotely practical purely electric vehicle. But there's also no remotely practical hydrogen-powered vehicle. While the vehicles themselves may be efficient (there are plenty of prototype hydrogen-powered buses being tested in North American cities, and they work just fine), the lack of a distribution network and monumental expense of constructing one that is safe means that there can't simply be a shift from oil to hydrogen.
There is also the matter of on-site storage. A "gas station" that stored hydrogen instead of gasoline wouldn't be able to hire minimum-wage high school students to run the show anymore, not with hydrogen tanks and piping (aboveground or otherwise) running everywhere at upwards of 3,000 psi.
So that's why I think the notion that we can just jump over to a hydrogen economy is completely out to lunch.
As to what can and should be done about the impending hydrocarbon crisis, here's what I think:
There isn't one single alternative fuel source that can possibly meet world energy demand in the same way that gasoline meets it now. Barring a major new discovery -- on the magnitude of working cold fusion -- the best we can do is shift as much of the world's energy demand as we can to multiple alternative sources: sea wind farms, nuclear power, and yes, hydrogen.
I think that as far as transportation is concerned we should focus on hybrid gas/electric vehicles. Honda and Toyota have started this, and other companies are starting to license their technology. It's a much better approach than treating hydrogen as a magical cure-all solution the way the hydrogen economy's strongest advocates do, because a) it utilizes the existing, highly efficient petrochemical distribution network, b) unlike hydrogen, it actually reduces greenhouse gas emissions, and c) it helps make people aware that conserving hydrocarbons is important.
One place that I think hydrogen can make significant inroads is in public transit. Hydrogen-powered buses only need a couple of city-run fuelling stations that could afford to have an engineer, or at least a trained operator, on-site all of the time. That wouldn't require too significant a change in existing hydrogen distribution methods -- just bigger tanks. No pipelines, because it isn't all that much more hydrogen. Not several orders of magnitude more like it would be for a full-fledged network to fuel everyone's hydrogen car.
As to further in the future, I think electric vehicles are in some sense the answer... but that the North American Way is going to have to change significantly before that can happen. I'm not thinking of electric cars, here; I'm thinking of high-speed magnetically levitated electric trains. A network of them across the continent, combined with efficient electric or hydrogen-powered public transit, would mitigate the need for many families to own more than one or zero vehicles. However, this is dreaming on the same scale as a hydrogen distribution network and I don't see it anywhere in the near future. I do think, however, that this style of solution is better than developing a hydrogen distribution network.
Edit:
P.S. In my heart of hearts, though, I'm not sure that there is a solution to the hydrocarbon problem, because of the issue of plastic. I think we may have reached the stage where the problems we need to solve to survive and maintain any semblance of our current lifestyle have grown too complex for us to solve.
posted
In the context of perception, it doesn't matter that the Hindenberg explosion may not have actually been caused by hydrogen exploding, the hydrogen did explode regardless of how it started. But people's perception at the time, was that hydrogen was dangerous. People's perception is now that Nuclear power is dangerous.
The biggest problem now with hydrogen is its energy to volume ratio in gaseous form. This can be solved theoretically by fuel cells, since you are extracting the hydrogen at the point where you actually need it. If fuel cells don't work, then there will be tons and tons of hydrogen cylinders being transported everywhere, if the "hydrogen economy" actually happens. The thing is, that a hydrogen distribution network could actually happen using mostly existing infrastructure. There would be a costly retrofit to every gas station in the country but then it would become a "hydrogen station" and we'd be on our merry way. Do I think this is going to happen? I don't know. Because it is going to have to come from a radical paradigm shift in the population's consciousness. The radical shift will only be triggered by economic factors more than likely. Would the economy collapse completely before things change? I don't think so. I think once the warnings are clearly clearly there where everyone can see them, not just academics and some politicians, the collective consciousness will shift, to whatever we need to do as a species to survive.
Do I think the problems that the human race faces now are increasing in complexity faster than we can solve them? No. I think we sell human ingenuity way too short if we ever assume that.
One possiblity other than hydrogen, is a methane economy. We can grow bacteria and other forms of life that produce methane pretty effortlessly. Methane actually has fewer collection and distribution problems than hydrogen. Vehicles are already running sucessfully off of CNG particularly busses and other forms of public transport. I think a lot of things are changing incrementally, with CNG and other alternative fuels, that will also help facilitate the paradigm shift. The "hydrogen economy" is only one possible solution. The cry of people throughout history is "well it seemed like a good idea at the time" And whatever actually seems like the best idea at the time the crises actually becomes severe, is what is going to catch on, even if in hindsight it wasn't the best choice.
posted
Yes, that's true. Whether the hydrogen is extracted from within the car or whether it's extracted offsite, it still requires energy to create pure hydrogen.
I don't know how much energy it would take, but no fuel cell car is worth putting into production if the energy required to create the hyrogen is greater than the energy the hydrogen in turn produces for the propulsion of the vehicle.
That's really the crux of the issue.
[ May 23, 2004, 12:34 PM: Message edited by: Nick ]
Posts: 4229 | Registered: Dec 2002
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"but no fuel cell car is worth putting into production if the energy required to create the hyrogen is greater than the energy the hydrogen in turn produces for the propulsion of the vehicle."
That's not ENTIRELY true. While this would be desirable, fuel cell cars would also make sense if the energy used to produce the fuel cell was renewable and/or relatively non-polluting; in such a situation, we can "afford" to waste energy in order to transform it into a more portable and useful form.
Posts: 37449 | Registered: May 1999
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Well, no, not ENTIRELY true. Wouldn't we simply be reducing the amount of non-renewable resources that human beings consume?
I know this is an over-utopian idea that will probably never happen, but I hope that we can generate enough hydrogen to run all the cars in the world with just our natural power sources (wind generators, hydro-electric dams ect).
posted
Switching to hydrogen while maintaining roughly the same number of vehicles per person in North America wouldn't really fix much of anything. You would still need to get an obscene amount of energy from somewhere. Right now, ironically, most hydrogen is made with power supplied by -- you guessed it -- burning hydrocarbons.
Also, water vapour is a greenhouse gas. Just think for a minute about what New York would be like if every single car in it spat out water vapour. It would be the most humid place on earth.
A move away from this notion that everyone has to have his or her own vehicle is what's required to get around the energy problem, and the notion that hydrogen is some sort of miracle fuel and we can all just sort of switch our cars to it doesn't help that happen. Hydrogen-powered cars for everyone are not the answer.
posted
Twinky you are forgetting everything you learned about combustion. Breaking long chain hydrocarbons we are already spewing out water right and left in the exhaust. A little more water in the atmosphere, greenhouse gas or no isn't going to make any difference.
Besides everyone goes "greenhouse gas" HORRORS. What people forget is what the rate limiting step of photosynthesis is: Grabbing the CO2 from the air. Having more CO2 in the air will cause plants to grow better, if there is also water. I don't think there is any real need for crisising over that fact. If the sea level does rise in the next couple hundred years people will either build dikes or move inland. I don't see it being the total cataclysm that a lot of doom and gloomers predict. We could end up with a tropical rainforest type ecosystem again, and that wouldn't be the end of the world.
posted
Well, supposedly the planet has been much hotter in the past without triggering any kind of runaway effect--no polar caps at all at several points. (I too would be running my air conditioner.)
It would however, mean a lot of people relocating. I don't really think we can afford to build dikes around the entire state of Florida, for instance. OTOH, Antarctica would open up.
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I think there are too many acronyms now. IIRC, OTOH. Stop with that. What's next, IUTMA? (I use too many acronyms?)
Posts: 4229 | Registered: Dec 2002
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posted
Only to a point though. At somepoint the rate of additon of CO2 exceeds the rate at which plants can use it.
Other things come into play as well. Most of the CO2 users are ocean born plankton. Sure they're sturdy, but we don't want rapid ocean temp changes. We need them; I like them; they give me oxygen.
Any way, it might not be then end of the world if we went back to a tropical climate, but it should wouldn't be a picnic either.
Posts: 1621 | Registered: Oct 2001
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posted
>> Twinky you are forgetting everything you learned about combustion. Breaking long chain hydrocarbons we are already spewing out water right and left in the exhaust. A little more water in the atmosphere, greenhouse gas or no isn't going to make any difference. <<
I disagree, though it depends in part on the cell stack efficiency and throughput. My point, though, is that not only do fuel cells not solve the problem, they don't help us at all in that regard... and I think it's something we need to be thinking about before whatever changes we're helping along become irreversible.
As to photosynthesis, we are spewing out greenhouse gases while cutting down trees that would otherwise mitigate the effects of what we're doing. I don't predict a cataclysm -- rather, the problem is that we don't know what's going to happen if we keep going on as we do. If we had so much as a clue it wouldn't be on my list of long-term concerns along with the coming hydrocarbon shortage.
And I think my principal point, which is that fuel cells are very much not The Answer and that hydrogen is not the way to fuel the world, still stands.
Edit:
P.S. I think methane is good, though. Especially if we can harness the power of cow farts
posted
As long as we're talking about alternative fuel... I'm not that knowledgable about the subject, but biodiesel seems an interesting prospect. A fair amount of existing waste can apparently be converted into fuel and you get more energy out than you put in (the "extra" energy is really just solar energy). I understand it also doesn't stink as much as conventional diesel.
Posts: 4534 | Registered: Jan 2003
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Yes, I don't really know what is going to happen. But whatever does happen is in generally is going to be influenced a lot more by public perception and a lot less than hard science than us engineers would like.
Maybe talking about the "hydrogen economy" in the academic arena will actually filter out to the general populace. But the dessemination mechanism is somewhat lacking. If you asked your average Canadian on the street. "So what do you think about the possiblity of a hydrogen economy?" what answers do you think you would get?
I know in the U.S. a blank stare would probably be a positive response... AJ
Posts: 11265 | Registered: Mar 2002
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posted
It's my understanding that the long-term contribution of a particular fuel to the CO2 in the atmosphere is related to how long the carbon being burnt has been in fixed in the biomass. So fossil fuels have a huge impact because they release carbon that has been excluded from the carbon cycle for millions of years, burning trees has a lesser but still noticable impact, and burning fuel derived from shorter lifespan plants has an impact of much less significance.
posted
I think I can agree with that Dagonee. Which is why with the hydrogen have less impact because you are just releasing H2O that was already in the water cycle to begin with, if in the ocean before.
posted
Why the heck would it matter whether the carbon has been dormant for a long time? It sound like you are talking about carbon that has spoiled. Or is it just that we're adding carbon to the atmostphere that has been underground for a long time?
Posts: 16551 | Registered: Feb 2003
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because m_p_h before a hundredish years ago, the global environment was basically in equillibrium with the carbon cycle as it had been for a very very long time. To add additional carbon to the carbon cycle(carbon that has been out of use since the Dinosaurs), at the same time biomass is being destroyed is most definitely going to shift it out of equillibrium. I am on the side that generally thinks that the equillibrium will right itself over time and incorporate the new carbon. But the other side has just as powerful arguments for the outcome where it becomes irreversably skewed and the global environment will go into an uncorrectable downhill slide.
posted
I remember reading about a year ago that some scientists now think that fossil fuels did not, in fact, come from biomatter. Does anybody else know anything about this?
Posts: 16551 | Registered: Feb 2003
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posted
MPH - an annual plant gets most (all?) of it's carbon from carbon dioxide in the air. If the fuel gets all it's carbon from annual plants, then each year that fuel source has a net zero effect on carbon in the air.
Assume 100% of the carbon comes from the air. Let's say the plants have 100 tons of carbon. All that came from the air, and returns to the air as CO2 when it is burned (either directly or when converted to biodiesel). So the net effect from seed planting to burning is zero (minus 100 tons of Carbon from air as it grows, plus 100 tons as it was burned).
Even if a lower percentage of the carbon in the plant comes from the atmosphere, the effect is still less than if something that didn't extract carbon from the air is burned.
Oil, coal, etc. come from carbon that has not been in the atmosphere for millenia, so the carbon produced by them is directly added to the atmosphere.
Dagonee P.S., obviously, this explanation is oversimplified, ignoring energy costs, etc.
posted
I heard a report a while ago, don't remember the specifics, that said hydrogen might be bad for the Ozone and/or upper atmosphere. There just weren't enough tests done and that the project should be put on hold untill we know for sure...as we might cause more damage with that than with fossil fuels. Anywone know anything about this?
Posts: 4953 | Registered: Jan 2004
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posted
Seems very unlikely - any water vapor in excess of what the air can hold will simply condense out of the air. Bad for humidity, but isn't that way to low in the atmosphere to affect the ozone?
Unless they're referring to free hydrogen escaping the system. I don't know what that would do.
posted
It was the free hydrogen. Apparently it works as a catalyst the same way as CFCs. Not sure whether they proved this conclusively, though, or showed how much of an effect it would have for reasonable estimates of leakage.
Posts: 1810 | Registered: Jan 1999
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posted
Hmmm...then it seems we need a way to make sure we burn it all.
After-burners on our Toyotas, anyone?
However, I'm pretty sure there's no free energy lunch anywhere. Wind turbines kill birds, hydrogen kills ozone, and I'm pretty sure reading under a lightbulb powered by solar energy gives you skin cancer.
As opposed to reading under a lightbulb powered by, say, a treadmill? I suppose that'd probably be good for your heart...
Posts: 1810 | Registered: Jan 1999
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posted
Ooh - good one. I'll connect my reading lamps to the fitness equipment in the basement and watch those pounds melt away!
Posts: 26071 | Registered: Oct 2003
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I liken the hydrogen economy and Linux to Laserdiscs. Good concept, shitty execution, and Im just waiting for the dvd of fuels and operating systems to come along. Posts: 2532 | Registered: Jul 2001
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