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Electricity + Water (Score:5, Interesting)
Then again, so would a huge flywheel or a bunch of batteries.
Re:Electricity + Water (Score:5, Informative)
Or you could do what most people do when they want hydrogen, heat a hydrocarbon with steam [wikipedia.org]. It is a hell of a lot cheaper than electrolysis! In fact, most fuel cells use some sort of hydrocarbon reforming to get their hydrogen. Unless you store hydrogen as a liquid, its energy density is just too low for any reasonable fuel tank.
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The real problem here is the space required by sugar-cane plantations. To be able to supply enougth methanol the plantations would have to grow over lands ocuppied today by other cultures (we still need food!), or the few preserved wild forrests that we have. Yes, I know we can harvest methanol from beats a
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If you used BioDiesel as a fuel you wouldn't have to rely on the technology curve.
It's over 100 years old, proven, affordable, reliable, and can be ported from homes to cars with a MUCH higher factor of safety than hydrogen gas.
It's already has a distribution system infrastructure.
You can create BioDiesel from a wide range of plants that grow in all but one or two agricultural zones.
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The main problem with Nuclear today is the absence of recycling the material after it has been in the reacotr. Once we get breeder reactors and a recycling program going, nuclear gets a lot cleaner.
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There aer many strategies - I guess that I just picked one that doesn't put a bunch of hydrogen in one spot. I was located in an area affected by the blackout of 2003 so putting all of the eggs in one basket just never seems like a good idea to me anymore.
I suppose it would be a good idea to build a power plant on an empty natural gas formation and store all of the generated hydrogen in there. It would certainly help meet the needs during the day and do so with a smaller footprin
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Instead, they take some other compound, like ammonia or hydrides, from which they extract the hydrogen to power the fuel cell. The advantage is that at no point do you have a large enough quantity of hydrogen to cause an explosion.
So my point is, generating the appropriate "fuel" for a fuel cell isn't as easy as elec
Re:Electricity + Water (Score:5, Informative)
That's because there are no fuel cells aimed at the mass market yet, except alcohol testers, which are anyway not a power source. Hydrogen is not more dangerous than gasoline; it does not concentrate on the ground but escapes high to the sky. You can neither be soaked in hydrogen. It does however have a lower threshold for ignition, but putting things together it is not especially dangerous. Thinking Hindenburg, less than half of crew and passengers actually died [wikipedia.org]. Try find that number in any plane crash with an equivalent amount of flames.
Wish it were like that, but if they contain the energy, hydrides, ammonia or whatever else can also burn. The idea is mostly to increase volumetric energy density, as hydrogen is very light and going around with a 70-MPa cylinder is somewhat unpractical (though not impossible).
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Re:Electricity + Water (Score:5, Funny)
Carbon. Link 8 carbons or so in a chain, and populate the remaining bonds with Hydrogen. It forms a stable, energy dense, easily transportable liquid. As an added bonus, you don't need to do any additional processing to use it in that state, just burn it in your existing internal combustion engine.
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Hindenburg explosion not H2 but FeO3&Al (Score:5, Informative)
In addition, the skin panels were not electrically bonded to the superstructure of the ship and formed a series of capacitors which were highly charged - when the ship was grounded by the mooring lines, the panels discharged, some through the wet cords binding them to the ship, some by arcing (and thus setting themselves on fire).
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Re:Hindenburg explosion not H2 but FeO3&Al (Score:3, Interesting)
Rubbish (Score:4, Insightful)
There was no butyl rubber involved, but other than that, you have picked up on the revisionist Incendiary Paint Theory. It is voodoo science, nonsense on the face of it, and has been completely discredited through logic, investigation, and experiment; see Definitive rebuttal and many good links [colorado.edu]. The best minds in the field of airship history hashed this out in extreme detail, going over and over every angle. I know because I was involved in some of the debates.
Incendiary Paint Theory proponents who completely reject evidence and experimental findings are never able to explain away the DOZENS of other hydrogen filled airships which were lost through catastrophic hydrogen fires. None of them were doped with the Magic Incendiary Potion.
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Ultimately, this depends on population density and the efficiency advantage of the large-scale approach.
For any generation method limited by Carnot cycle efficiency, this is true. But fuel cells do not have this limit, and their efficiency does not increase very much with their size. Also, given that most homes already have some sort of chemical energy (natural gas or oil) delivered for heating, they
And that is a bad idea. (Score:3, Insightful)
You keep using that word. (Score:5, Informative)
I do not think it means [reference.com] what you think it means.
Hydro... power? (Score:4, Insightful)
Nope, looks like the submitter just has no idea what it means. Only reference to that in the article is an link to another article that does indeed talk about water power.
As far as 'where to get it'... I've always wondered where they thought they'd get unlimited amounts of any limited resource. We can't destroy the oceans for it, and we can't scoop it out of the sun. (At least, I think we can't.) The article talks about nuclear and fossil fuels... That's the problem we already have... How is this a solution?
We're going to have to sit down and decide to be responsible about the environment some day. We can't keep putting it off forever.
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Re:Where to get this? (Score:2)
The only advanage that Hydrogen really supplies in my mind, is that "making" will be ran 7x24 at near continous optimised loads, where the power that is being consumed is at or near maximum efficiency. Like Diesel-electric locomotives, that run the main 2-cycle e
What about Iceland? (Score:5, Interesting)
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Re:What about Iceland? (Score:5, Informative)
http://www.hydro.com/en/press_room/news/archive/2
http://business.guardian.co.uk/story/0,3604,94313
They don't just use hydrogen.
http://www.newscientist.com/channel/earth/energy-
They are lucky they live where they do. It's a hot bed of free energy.
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Coal to oil (Score:2, Interesting)
With oil running out in +/- 43 years we are already started very late to start working on good solutions. I think that we, in the end will be working with the coal liquefaction solutions. Creating oil from coal is already done on large scale in South Africa.
We will not be able to change all current diesel driven machines to a other power source so I think this will become to gap closer until we find a better solution. I really wonder what the governments aroun
Re:Coal to oil (Score:5, Funny)
~Rebecca
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Re:Coal to oil (Score:5, Funny)
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The myth of peak oil (Score:3, Insightful)
I've seen this prediction-of-doom vary from 10 years to 50 years.... projected at various points over the last 30 years. Chances are, you'll be able to see some headline in 2070: "Oil Running Out in 20 Years!!!"
Re:The myth of peak oil (Score:5, Informative)
Amazing how you don't graps what "Peak Oil" really is.
At a certain point, production stops increasing, and in fact starts to decline, because not enough new fields can be found to replace the spent ones. (When's the last time you saw a field of Oil pumps in PA?) The price of oil goes up, as the supply goes down -- making currently non-profitable oil reserves and energy sources, theoretically, more profitable.
We will likely never run out of oil, although it will eventually (50 years? 500?) reach the point where it's simply too expensive to get the stuff out of the ground, and we only use biomass-made oil or some other alternative fuel source.
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Increase in price is the problem (Score:3, Interesting)
This is a true statement. However, what you're not really discussing -- and what really lies behind the worries of people discussing Peak Oil -- is what the social consequences of that increase in cost will be.
As energy becomes more expensive, the lifestyles that we currentl
Hydrogen Not A Fuel? (Score:5, Insightful)
How is hydrogen not a fuel? I always thought fuel was a substance that when it goes through a chemical reaction releases energy. While many fuels are burned, the process of generating energy in a fuel cell is still a chemical reaction.
Secondly, aren't there other fuels that have to be made before we can use them? Gasoline and diesel have to be refined -- it's not like we find them naturally in the ground.
So hydrogen is just a way of "storing and transporting energy". I thought the use of fuels was a way to "store and transport energy".
Re:Hydrogen Not A Fuel? (Score:4, Informative)
The more things change. . .
Gasoline and diesel have to be refined -- it's not like we find them naturally in the ground.
But the energy is already in the crude (stored solar) and it can be used to power its own refinement. There is a loss of available energy in the process, but a net gain nonetheless.
There is nothing but net loss in hydrogen since any energy that can be extracted from it must be put in it the first place - and the Second Law wins. The current cheapest and quickest way to put energy into hydrogen is to . .
In other words, when hydrogen becomes really, really expensive itself.
KFG
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Re:Hydrogen Not A Fuel? (Score:4, Interesting)
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Crisis is in Transportation sector. (Score:5, Informative)
The fixed or stationary energy use, at homes, offices, and factories is not in as much of a crisis as the transportation sector. For electricity generation, there are alternatives like coal (yeah, it is dirty), or nuclear (yeah, most people fear it) or tar sands (yeah, it is expensive to recover) or wind (yeah, it has some problems), solar (yes, it needs high investment). There are problems, but USA is self suffiicient in them, and we wont be held hostage by foreign powers. There is breathing space to develop really good alternatives.
On the other hand, in the transportation sector is in crisis already. So much of personal transportation depends on gasoline and freight depends on diesel and air transportation depends on kerosene. No serious alternatives are emerging and the time is running out on those sectors. Most predictions of peak oil is around now or 2010. Even the most optimistic estimates about the Hydrogen powered cars or biodiesel driven trucks talk about widespread adaptation around 2020.
America is particularly vulnerable to this energy crisis. It is not as densely populated like Europe or Urban India and China. It is not easy to switch USA to use electricity driven public transportation. So much of the economy depends on the high home values of the sprawled cities and the humongous fleets of trucks delivering goods. So much of the infrastructure is built around the idea it is very cheap to transport goods over 100s of miles. And America is not self sufficient in this energy sector. This is a grave crisis.
Re:Crisis is in Transportation sector. (Score:5, Informative)
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A better approach (Score:3, Interesting)
Hydrogen is not an energy source, it is transmission medium. We already have a highly effective transmission medium: electricity. Improvements in our electricity generation and distribution systems would be a simple, incremental means towards a more diverse energy generation portfolio.
The main problems are battery technology for mobile applications, and long distance transmission. The inability to ship electricity across the continent divides our nation into geographic markets; it is not possible to harvest wind energy in North Dakota and sell it in California. In my state of Massachusetts there is a huge brouhaha over a massive ocean based wind farm right off the coast of our prime tourist area. This farm would be unnecessary if we could buy wind power from distant land based wind farms.
The answer would be a national superconducting electricity grid.
One advantage of a national super grid would be that it would create a superior storage medium for renewable but variable sources, such as solar voltaic, wind and tidal power, by converting them to natural gas and diesel fuel reserves with near perfect effiency.
Huh?
It's simple: we have already natural gas and diesel plants that burn fossil fuels and supply a major fraction of our electricity. If they don't burn as much fuel because a distant, renewable source is providing power to the local grid, the difference in fuel is saved. From a national viewpoint, if that renewable energy had been magically converted into diesel oil, tbe practical result wouldn't be any different, on the "penny saved is a penny earned" theory.
A superconducting grid may also be the missing incremental step towards increased hydrogen use. The superconducting transmission lines would have to be cooled. If liquid hydrogen were used as a coolant, then it would provide an alternative (but less efficient) form of energy storage to saved fossil fuels. The producers would provide a mix of hydrogen and electricity and inject them into the transimission line. On the receiving end, the hydrogen would be gasified and converted into electricity at a rate sufficient to maintain cooling in the transmission line.
This would provide a local source of liquid or gasified hydrogen that could be piped or tankered to power hydrogen fleet vehicles at the outset. An example might be post office delivery vehicles, for whom a daily range of a couple of hundred miles is acceptable; or possibly some mass transit buses that take many short distance trips and could be refuled during the day. If there were other local uses for the hydrogen, then the local terminal would request more and the producers would alter their electricty/hydrogen mix. However if hydrogen is outstripped by battery technology, then the basic infrastructure is still useful.
The best part of this is that it could be done much faster than a fossil fuel to hydrogen transition.
EEstor or advanced flywheels seem better. (Score:4, Insightful)
Wouldn't a better battery be a much better solution. We already have the distribution network(electric grid). EEStor ultra capacitors seem to be that better battery if they deliver on promises, but there are also advanced flywheels (composite wheels in a vacuum, superconducting magnetic bearings, turning neark 100k rpm). These can be charged or discharge quickly and should last the life of the vehicle.
http://tyler.blogware.com/blog/_archives/2006/1/1
http://www.wired.com/wired/archive/8.05/flywheel.
Fuel cells don't solve any energy creation issues and as a deliver mechanism, it doesn't seem so hot, I would much prefer to stick with mechanisms we aleady have like the electric grid.
Electricity -- Not Hydrogen (Score:4, Insightful)
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easier to make a bomb with Diesel then hydrogen
Quite easy to make a bomb with Diesel (Score:5, Funny)
After XXX [imdb.com], Riddick [imdb.com] and A Man Apart [imdb.com], Hollywood knows how easy it is.
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That's quite a strawman you're propping up there! Proponents of a hydrogen economy propose using hydrogen as a means of storing energy produced in a variety of manners, including wind, solar, geothermal, hydrodynamic, etc. Did you even read the article?
The posting that you are responding to claims that we shouldn't generate the hyrdrogen at the source of the energy production, but rather convert it to electricity and then us
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Jamaica produces Sugar from cane and sells it at a loss (weird Jamaican politics that I won't get into). However Appleton estate is profitable, unlike the rest. Why? they grow sugarcane to make rum. That rum attracts premium prices.
Rum is technically byproduct of the waste from sugar production. Just like Molasses and Bagas (wood substitute). Since these goys figured out how to cover the total cost off a single byproduct any money made from selling the other stuff
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He's not wrong, merely imprecise. You might be considered either wrong, or ill informed. Your choice. I can't just pick overly critical, as that doesn't fit. (Well, it's true, but it's not the point I'm addressing.)
It would have been more correct to point out that dumb means unable to speak rather than unintelligent. This is at least formally t
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median
noun
3. Arithmetic, Statistics. the middle number in a given sequence of numbers, taken as the average of the two middle numbers when the sequence has an even number of numbers: 4 is the median of 1, 3, 4, 8, 9.
average:
3. Statistics. see arithmetic mean.
arithmetic mean
Statistics. the mean obtained by adding several quantities together and dividing the sum by the number of quantities: the arithmetic mean of 1, 5, 2, and 8 is 4.
(Also called average)
Since the OP is attemp
Well... (Score:2, Funny)
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Immediately before that quote: Skeptics say that hydrogen promises to be a needlessly expensive solution for applications for which simpler, cheaper and cleaner alternatives already exist. (Emphasis mine)
In other words, for many applications Hydrogen is the Rube Goldberg machine of energy management.
=Smidge=
Re:Storage as a "compound" (Score:4, Informative)
The temperature needed to release the hydrogen is about 300 deg C.
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Climatology is full of scientific uncertainties (Score:5, Insightful)
Climatology is full of uncertainties, and the general agreement among scientists goes only so far. The most important area of agreement is that CO2 operates as a greenhouse gas, but the extent of its contribution within the overall system is commonly misrepresented.
CO2 is not the most important greenhouse gas, by a long chalk. Water vapour is the primary greenhouse gas on Earth, directly responsible for 95% of the global warming that keeps the planet from freezing solid to a dreadful -19 C or so. Global warming is essential.
Climate modellers who want to highlight CO2 choose not to make that known to the man in the street, and the way they treat water vapour as a "feedback" in the GCM models instead of as a key mechanism of "forcing" tends to brush the importance of water vapour under the carpet. It's a somewhat questionable scientific approach because pure feedbacks should really be invariant linear amplifiers and not highly variant in their own right (as is water vapour), but what's worse is that this creates a hugely inaccurate public perception.
The simple fact is that we live on an ice, water, and water-vapour covered globe moving in a somewhat complex way around a somewhat variant Sun, and that is the PRIMARY driver of climate, with water as its main agent of heat distribution and with just enough natural global warming to make it liveable, in between ice ages. CO2? Yes, it's relevant and it does have an effect, but it's not even close to being a primary player, and reducing our CO2 emissions will not have a significant effect in anybody's realistic scenario.
And that's not under dispute by any scientist --- they know the maximum extent of possible direct warming per ppm of CO2, and they also know the maximim warming amplified through water vapour feedback in a cloudless atmosphere. But they're not even close to understanding well the magnitude of interactions in the upper atmosphere nor being able to model cloud formation well enough to determine what the real effect of 2X or 3X CO2 would be. To claim that anything in that area of climate forecasting is "established without doubt" is a total distortion of the truth.
What's more, the natural variation in temperature across glaciation cycles totally swamps the changes calculated by any existing climate model, which just shows how we know very little in the larger context. We're right at the "natural" end of the current 18,000-year inter-glacial period, so expect a massive drop in temperature any century now. Can the GCMs predict that? Of course not.
The uncertainties in this area are LARGE. They will be worked out. In the meantime, only non-scientists claim clearcut knowledge.
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