What is Hydrogen Fuel?

[YoungJoonKim]

Is hydrogen fuel literally "WATER?"
If so, how is this sustainable when the world's fresh water supply is at such a risk...
If...we turn water into alternative energy for our car, how much are left for us to drink?

Is this even a viable option for future?

 

[iARTthere4iam]

Is hydrogen fuel literally "WATER?"
If so, how is this sustainable when the world's fresh water supply is at such a risk...
If...we turn water into alternative energy for our car, how much are left for us to drink?

Is this even a viable option for future?

Umm? No. Hydrogen is Hydrogen. Ever hear of Elements? Hydrogen is one of the most simple and abundant. Please look at a periodic table.

Hydrogen is something that can be burned to produce energy. Water contains Hydrogen. We can get hydrogen out of water and are left with oxygen. Nice. We don't have to use fresh water to get hydrogen and there is lots of water, lots and lots of water all over the earth, in the earth, under the earth, and above the earth. There is vast quantities of hydrogen and it is not made of any carbon, it is hydrogen. So no carbon emissions. Nice.

Say you take aluminum and add water, the oxygen in the water will attatch to the aluminum and leave hydrogen which can then be used as an energy souce. nice.

 

[Niflmir]

The easiest way to get hydrogen is unfortunately from fossil fuels. Electrolysis can be used but it is terribly inefficient. The cleanliness of the hydrogen largely depends on your ability to create it cleanly, since burning it merely produces water. (Possibly some peroxides, I am not certain.)

Unfortunately hydrogen is small enough to tunnel outside of most containments, and energetic enough to escape the atmosphere at standard atmospheric temperature. So our supply of hydrogen would slowly dwindle even if we captured the vapor and electrolysed it. The problem of hydrogen fuel is largely the problem of storing it properly.

 

[Walter]

The Hindenburg springs to mind. Oh, the humanity.

 

[hermanntrude]

The Hindenburg springs to mind. Oh, the humanity.

fortunately, petroleum doesnt burn

 

[hermanntrude]

what we really need is a fuel that doesn't burn.... hmmmm

 

[hermanntrude]

deleted

 

[Niflmir]

Electricity, but it is quite inefficient, generally. Actually, I should look into the efficiency of those trains based upon superconductors...

 

[MikeyDB]

For an idea of the power of hydrogen....look up look way up....see that big yellow thing in the summer sky....

 

[#juan]

There are good things about hydrogen as a fuel. When you burn hydrogen the product of that combustion is water. Hydrogen is one of the lightest elements so any leaked hydrogen would head straight for the stratosphere. One of the problems with hydrogen is storage. To store a useful amount of hydrogen in a reasonably sized container, it has to be stored at very high pressures. There are ways to store hydrogen at more reasonable pressures using catalytic materials but as yet the cost is still prohibitive.

 

[iARTthere4iam]

For an idea of the power of hydrogen....look up look way up....see that big yellow thing in the summer sky....

That is right. Unfortunately nuclear fusion is not quite ready for commercial application on a large scale. Nuclear fission on the other hand...

The best plan that I have heard about involves a changeable cell of pure aluminum. Just add water and the oxygen and aluminum react to create aluminum oxide hydrogen is the byproduct that can be used as fuel. When the aluminum is spent it is replaced by more aluminum and water is added. This does away with having to store large quantitiies of hydrogen. Unfortunately aluminum is usually in the form of aluminum oxide and it takes energy to get aluminum to give up oxygen. Damn Newton.

 

[#juan]

Umm? No. Hydrogen is Hydrogen. Ever hear of Elements? Hydrogen is one of the most simple and abundant. Please look at a periodic table.


Say you take aluminum and add water, the oxygen in the water will attatch to the aluminum and leave hydrogen which can then be used as an energy souce. nice.

Sounds good but it's not quite that simple. In order to have the process you describe, you need gallium which is as rare as gold and very expensive.

http://tinyurl.com/ypxtf7

 

[iARTthere4iam]

Sounds good but it's not quite that simple. In order to have the process you describe, you need gallium which is as rare as gold and very expensive.

http://tinyurl.com/ypxtf7

No cost is too high for my car.

as long as you are paying

I actually don't think hydrogen will end up the technology of choice for automobiles. Electric cars are here if we choose to allow them. There are at least two functioning electric cars being built in Canada and if Transport Canada would allow it they would be running around cities right now. It does not solve our energy needs, we still need to charge the cars with some type of energy produced from somewhere.

 

[Niflmir]

With electrical cars you end up depending on the source of electricity, which is still mostly fossil fuel based and needs to change. The problem then becomes the long term safe storage of electricity: batteries. Which are pretty heavy, and dirty to dispose of.

 

[#juan]

No cost is too high for my car.

as long as you are paying

I actually don't think hydrogen will end up the technology of choice for automobiles. Electric cars are here if we choose to allow them. There are at least two functioning electric cars being built in Canada and if Transport Canada would allow it they would be running around cities right now. It does not solve our energy needs, we still need to charge the cars with some type of energy produced from somewhere.

Right now the plug-in hybrid looks like a good bet. Electric cars seem to be the most sensible alternative to internal combustion but without a decent range people won't buy them so the hybrid is a step in the right direction.

 

[Walter]

There are good things about hydrogen as a fuel. When you burn hydrogen the product of that combustion is water.

Water vapour makes up over 95% of all greenhouse gases. We'll be contributing even more to AGW. What will Gore and Skuzuki say?

 

[#juan]

Water vapour makes up over 95% of all greenhouse gases. We'll be contributing even more to AGW. What will Gore and Skuzuki say?

It is not quite that simple Walter.

2005-01-20

Water vapour is not the dominant greenhouse gas

OK, so it may not surprise you that I'm going to have to qualify the headline a bit lower down, but the point itself remains.

Why does anyone care about this? Answer, of course, that one of the std.septic arguments is "there is no point in worrying about human emissions of CO2, because water vapour is the dominant GHG". This argument is nonsense (which is why there is no k) but if you don't know the science thats no obvious. So...

Lets start by looking at what fraction of the current GHE *is* caused by water vapour. Its not terribly easy to find these estimates, mostly because scientifically its not an interesting question (see below). The ones I've found I've collected onto the wiki page Greenhouse effect; refs to all of this are available there. Probably the best one is IPCC '90 (first report; sadly not online) which estimates 60-70%. I presume thats a global value. Locally, instantaeously, it would vary wildly according to local conditions. If you start omitting various gases, you can push the numbers up high: Soon and Baliunas quote 88%, considering only WV and CO2. Lindzen quotes 98% (Even if all other greenhouse gases (such as carbon dioxide and methane) were to disappear, we would still be left with over 98 percent of the current greenhouse effect). I don't think thats plausible (incidentally I seem to have misrepresented it on the wiki page... oops). He doesn't quote a source for this value and may well have made it up. But apart from providing word-bites for skeptics to take out of context, there doesn't seem to be much point in these numbers. Because the main point is...

Water vapour is a "reactive" GHG with a short atmospheric lifetime of about 1 week. If you pump out a whole load of extra water vapour it won't stay in the atmosphere; it would condense as rain/snow and we'd be back to where we started. If you sucked the atmosphere dry of moisture, more would evaporate from the oceans. The balance is dynamic of course: humidity of the air varies by place and time, but its a stable balance.

In contrast, CO2 has a long lifetime (actually calculating a single "lifetime" for it doesn't work; but a given CO2 pulse such as we're supplying now will hang around for.. ohh... a century or more). It doesn't rain out (amusing factoid: the surface temperature of the deep interior Antarctica in winter can be colder than the freezing point of CO2; but this doesn't lead to CO2 snow (sadly, it would be fun) because the freezing point is lower because of the lower pressure because its higher up). So if you put in extra CO2 the climate warms a bit; because of this move WV evaporates (it doesn't have to, but just about all models show that the relative humidity tends to be about constant; so if you heat the atmos that means that the absolute humidity will increase). This in turn warms the atmosphere warms up a bit more; so more water gets evaporates. This is a positive feedback but a limited one: the increments (if you think of it that way) get smaller not larger so there is no runaway GH effect.

So: adding CO2 to the atmosphere warms it a bit and ends up with more WV. Adding WV does nothing much and the atmos returns to equilibrium. This is why WV is not the *dominant* GHG; its more like a submissive GHG

[Update: 2005/02/09: http://www.radix.net/~bobg/climate/halpern.trap.html is worth reading]

 

[Walter]

Water vapour is not the dominant greenhouse gas

So: adding CO2 to the atmosphere warms it a bit and ends up with more WV. Adding WV does nothing much and the atmos returns to equilibrium. This is why WV is not the *dominant* GHG; its more like a submissive GHG

[Update: 2005/02/09: http://www.radix.net/~bobg/climate/halpern.trap.html is worth reading]

VIRGINIA KEY, FL (October 6, 2005) — A new study published in this week's issue of Science confirms evidence of global warming using satellite measurements of water vapor — a well-known greenhouse gas — in the troposphere.
Using satellite measurements of water vapor from 1982 to 2004, Dr. Brian Soden from the University of Miami Rosenstiel School of Marine & Atmospheric Science, and colleagues were able to confirm the climate model simulations that have long indicated that moisture is increasing in the upper troposphere and this water vapor build up is exacerbating global warming. Their findings are published in the paper, “The Radiative Signature of Upper Tropospheric Moistening.”
“The importance of water vapor in regulating climate is undisputed. It is the dominant greenhouse gas, trapping more of the Earth's heat than any other gaseous constituent,” wrote Soden and his co-authors Darren L. Jackson from the University of Colorado Cooperative Institute for Research in Environmental Sciences, V. Ramaswamy and M.D. Schwarzrzkopf from NOAA's Geophysical Fluid Dynamics Laboratory, and Xianglei Huang at the Princeton University Atmospheric and Oceanic Sciences Program.
Water vapor is not only the dominant greenhouse gas, but its concentration also depends strongly upon temperature. As the climate warms from the burning of fossil fuels, the concentrations of water vapor are expected to increase. This moistening of the atmosphere, in turn, absorbs more heat and further raises the temperature. In this way, water vapor greatly amplifies the global warming projected to occur over the next century.
http://64.233.167.104/search?q=cach...inant+greenhouse+gas&hl=en&ct=clnk&cd=1&gl=ca

 

[jimshort19]

Water is just hydrogen rust.