will the US military power dominate the world

"Seraphim" wrote in message
.. .
Stephen Harding wrote in news:3F994B53.FACA123
@cs.umass.edu:

Ralph Savelsberg wrote:

Great! However, the big question that very few people seem to be able
to
answer (myself included) is where the energy to make the H2 should come
from?

Natural gas. Mix methane (CH4) and very hot steam (H20) to produce Carbon
Dioxide (CO2) and Hydrogen (H2). This is a very well known process, and is
(was?) commonly used in the industrial production of chemicals.


Why not just use the methane directly and not incur
all the losses conversion brings with it ?

Keith

In article ,
Seraphim wrote:

Stephen Harding wrote in news:3F994B53.FACA123
@cs.umass.edu:

Ralph Savelsberg wrote:

Great! However, the big question that very few people seem to be able to
answer (myself included) is where the energy to make the H2 should come
from?

Natural gas. Mix methane (CH4) and very hot steam (H20) to produce Carbon
Dioxide (CO2) and Hydrogen (H2). This is a very well known process, and is
(was?) commonly used in the industrial production of chemicals.

But the big problem for the eco-types is all of the C02.

If you're going to make that, you might as well just use gasoline.

Now, if this new algae-based process of making H2 works out, we'll get
H2 with a net *reduction* of C02.

--
cirby at cfl.rr.com

Remember: Objects in rearview mirror may be hallucinations.
Slam on brakes accordingly.

In article t,
Tank Fixer wrote:

However my city has extended that policy to converting road lanes to
bicycle lanes. Now we have unused portions of road and the traffic goes
even slower, producing even more polution.

Bike lanes are interesting. I saw a study a while back that suggests a
net *increase* in car/bike accidents when bike lanes are present.

Of course, I live in Orlando, the most dangerous US city for bikes and
pedestrians, so it's a fairly moot point...

--
cirby at cfl.rr.com

Remember: Objects in rearview mirror may be hallucinations.
Slam on brakes accordingly.

In article ,
Chad Irby wrote:

In article t,
Tank Fixer wrote:

However my city has extended that policy to converting road lanes to
bicycle lanes. Now we have unused portions of road and the traffic goes
even slower, producing even more polution.

Bike lanes are interesting. I saw a study a while back that suggests a
net *increase* in car/bike accidents when bike lanes are present.

That information has been out there since at least the early 1970s, from
of all places some studies done for the L.A.W. (League of American
Wheelmen, which was one of the very first bicycle advocacy organizations
from the 1890s.)

Of course, I live in Orlando, the most dangerous US city for bikes and
pedestrians, so it's a fairly moot point...

In article ,
Chad Irby wrote:

In article ,
Seraphim wrote:

Stephen Harding wrote in news:3F994B53.FACA123
@cs.umass.edu:

Ralph Savelsberg wrote:

Great! However, the big question that very few people seem to be able to
answer (myself included) is where the energy to make the H2 should come
from?

Natural gas. Mix methane (CH4) and very hot steam (H20) to produce Carbon
Dioxide (CO2) and Hydrogen (H2). This is a very well known process, and is
(was?) commonly used in the industrial production of chemicals.

But the big problem for the eco-types is all of the C02.

You can scrub out the CO2 by trapping it by forming carbonate (CaCO3?).

If you're going to make that, you might as well just use gasoline.

Now, if this new algae-based process of making H2 works out, we'll get
H2 with a net *reduction* of C02.

Cite? Sounds interesting.

In article ,
Steve Hix wrote:

In article ,
Chad Irby wrote:

Now, if this new algae-based process of making H2 works out, we'll get
H2 with a net *reduction* of C02.

Cite? Sounds interesting.

http://www.wired.com/news/technology/0,1282,54456,00.html

--
cirby at cfl.rr.com

Remember: Objects in rearview mirror may be hallucinations.
Slam on brakes accordingly.

In article ,
Chad Irby wrote:

In article ,
Steve Hix wrote:

In article ,
Chad Irby wrote:

Now, if this new algae-based process of making H2 works out, we'll get
H2 with a net *reduction* of C02.

Cite? Sounds interesting.

http://www.wired.com/news/technology/0,1282,54456,00.html

thanks!

In article ,
Seraphim writes:
Stephen Harding wrote in news:3F994B53.FACA123
@cs.umass.edu:

Ralph Savelsberg wrote:

Great! However, the big question that very few people seem to be able to
answer (myself included) is where the energy to make the H2 should come
from?

Natural gas. Mix methane (CH4) and very hot steam (H20) to produce Carbon
Dioxide (CO2) and Hydrogen (H2). This is a very well known process, and is
(was?) commonly used in the industrial production of chemicals.

Erm... The Methane comes from where, exactly? Right now there are 2
sources - underground pockets, and Bovine Ddigestive tracts. The
underground sources have teh advantage of being commercially viable,
but incurs the same environmental damage as drilling for petroleum,
adn it's much riskier to store and transport. I'd rather be next to a
nuclear power plant than an LNG storage facility. Since the idea of
cracking Methane to get Hydrogen is to reduce the amount og Co2 being
generated, this method also has no advantages. The C02 is still being
created, It's just occuring at your Hydrogen Generating Plant rather
than in the car engine, or space heater, or whatever. Hydrogen,
whether in gaseous or liquid form, has lousy engery density, as well.
You can gat about 10 times the BTUs (Kilocalories)/gubic ft/meter
[liter/gallon] using kerosene or gasoline. Frankly, you'd be better
off just burning the Methane.


I'm sure you're aware that H2 is not something you can dig up
from the ground. Perhaps our hope should lie with nuclear fusion, though
that's not without its own problems either.
In my opinion H2 not the answer to a possible energy/environmental
crisis. Focussing on H2 is just replacing one problem with another.

There's so dogone much H2 around that its use for energy is almost as
attractive as splitting atoms in the long term.

But yes, those H and O atoms really like to stick together, and the
energy it takes to coax them apart is problematic at the moment.

The energy will always be probematic if water is the only thing used. The
energy it takes to free the hydrogen will be equal to the energy you get by
running it through your fuel cell, assuming that there is no energy is lost
in the process (very unlikely). Now, there are ways around this. You can
introduce something else (like Methane above) which tends to help. Or you
can use 'cheap' energy, like solar or nuclear.

100% efficiency isn't just Very Unlikey, it's Bloody Impossible.
Don't they teach these kids Thermogoddamics any more?

--
Pete Stickney
A strong conviction that something must be done is the parent of many
bad measures. -- Daniel Webster

Here is a little cold H20 for th hydrogen crowd.

http://www.aps.org/units/fps/energy/

Check out where the hydrogen will come from.

-- Charlie Springer

(Peter Stickney) wrote in
:

In article ,
Seraphim writes:
Stephen Harding wrote in news:3F994B53.FACA123
@cs.umass.edu:

Ralph Savelsberg wrote:

Great! However, the big question that very few people seem to be
able to answer (myself included) is where the energy to make the H2
should come from?

Natural gas. Mix methane (CH4) and very hot steam (H20) to produce
Carbon Dioxide (CO2) and Hydrogen (H2). This is a very well known
process, and is (was?) commonly used in the industrial production of
chemicals.

Erm... The Methane comes from where, exactly?

I would assume that it comes from the same place it has always come from.

Right now there are 2
sources - underground pockets, and Bovine Ddigestive tracts. The
underground sources have teh advantage of being commercially viable,
but incurs the same environmental damage as drilling for petroleum,
adn it's much riskier to store and transport. I'd rather be next to a
nuclear power plant than an LNG storage facility. Since the idea of
cracking Methane to get Hydrogen is to reduce the amount og Co2 being
generated, this method also has no advantages. The C02 is still being
created, It's just occuring at your Hydrogen Generating Plant rather
than in the car engine, or space heater, or whatever.

Well, first half the hydrogen is comming from water, so you've converted
1 mol CH4 into 4 moles H2 and 1 mol CO2. Now, its been a while sence I
had chemistry, but IIRC Delta_H of formation of water is around -240
kJ/mol (240 * 4 = -960), and Delta_H of combustion of methane is -890
kJ/mol. So if you have a good source of superheated steam (eg a nuclear
power plant) its a pretty good deal.

As for the CO2 still being produced. Its a lot easier to do something
with one large source than it is to do with millions of tiny ones.
Traping the carbon (most likely in the form of calcium carbonate) would
be a heck of a lot easier in a big stationary plant than a tiny moveing
car.

Hydrogen,
whether in gaseous or liquid form, has lousy engery density, as well.

*This* is probably the single biggest hurdle faceing a hydrogen car.
Lousy is somewhat of an understatement.

You can gat about 10 times the BTUs (Kilocalories)/gubic ft/meter
[liter/gallon] using kerosene or gasoline.

IIRC its more like 5 or 6 times for liquid H2 vs gasoline, but the point
still stands.

I'm sure you're aware that H2 is not something you can dig up
from the ground. Perhaps our hope should lie with nuclear fusion,
though that's not without its own problems either.
In my opinion H2 not the answer to a possible energy/environmental
crisis. Focussing on H2 is just replacing one problem with another.

There's so dogone much H2 around that its use for energy is almost
as attractive as splitting atoms in the long term.

But yes, those H and O atoms really like to stick together, and the
energy it takes to coax them apart is problematic at the moment.

The energy will always be probematic if water is the only thing used.
The energy it takes to free the hydrogen will be equal to the energy
you get by running it through your fuel cell, assuming that there is
no energy is lost in the process (very unlikely). Now, there are ways
around this. You can introduce something else (like Methane above)
which tends to help. Or you can use 'cheap' energy, like solar or
nuclear.

100% efficiency isn't just Very Unlikey, it's Bloody Impossible.
Don't they teach these kids Thermogoddamics any more?

If I have a glass of water, and let it sit in perfectly isolated system
(no energy loss), are you suggesting that the few molocules of water that
turn into oxygen and hydrogen, and then back into water, will, if given
enough time, cause the energy of the system to decrease?