What is this unit - NM3H2 - in relation to
hydrogen production?

The '3' is a superscript, and the '2' is a subscript.

The specific citation was '4.5 kWh/NM3H2', at:
http://www.bellona.no/en/energy/hydr...002/22869.html

The only part I can't figure out is NM3.

Cubic nanomoles? That makes no sense.

Thanks for any help.

Bob

Front Office wrote:
What is this unit - NM3H2 - in relation to
hydrogen production?

The '3' is a superscript, and the '2' is a subscript.

The specific citation was '4.5 kWh/NM3H2', at:
http://www.bellona.no/en/energy/hydr...002/22869.html

The only part I can't figure out is NM3.

Cubic nanomoles? That makes no sense.

Thanks for any help.

Bob

Normal cubic meters.

See:
http://www.unc.edu/~rowlett/units/di...rmalcubicmeter

Also, you probably want to post to sci.chem, not "sci.chemistry."

"Front Office" wrote in message
...
What is this unit - NM3H2 - in relation to
hydrogen production?

The '3' is a superscript, and the '2' is a subscript.

The specific citation was '4.5 kWh/NM3H2', at:
http://www.bellona.no/en/energy/hydr...002/22869.html

The only part I can't figure out is NM3.

Cubic nanomoles? That makes no sense.

Thanks for any help.

Bob

The number of hydrogen molecules (N, in moles) depends
upon gas pressure (P), temperature (T), and volume (V):


P * V = N * R * T or N = ( P * V ) / ( R * T )

NM3 probably means 'a cubic meter of hydrogen at standard
pressure (1 atm) and temperature". Thus,

1 cubic meter of H2 at STP - 4500 Watt-hours

[Old Man]

Jim Black wrote:
Front Office wrote:

What is this unit - NM3H2 - in relation to
hydrogen production?

The '3' is a superscript, and the '2' is a subscript.

The specific citation was '4.5 kWh/NM3H2', at:
http://www.bellona.no/en/energy/hydr...002/22869.html

The only part I can't figure out is NM3.

Cubic nanomoles? That makes no sense.

Thanks for any help.

Bob


Normal cubic meters.

Thanks.

See:
http://www.unc.edu/~rowlett/units/di...rmalcubicmeter

Also, you probably want to post to sci.chem, not "sci.chemistry."

I'll check that out.

Bob

Old Man wrote:
"Front Office" wrote in message
...

What is this unit - NM3H2 - in relation to
hydrogen production?

The '3' is a superscript, and the '2' is a subscript.

The specific citation was '4.5 kWh/NM3H2', at:
http://www.bellona.no/en/energy/hydr...002/22869.html

The only part I can't figure out is NM3.

Cubic nanomoles? That makes no sense.

Thanks for any help.

Bob


The number of hydrogen molecules (N, in moles) depends
upon gas pressure (P), temperature (T), and volume (V):


P * V = N * R * T or N = ( P * V ) / ( R * T )

NM3 probably means 'a cubic meter of hydrogen at standard
pressure (1 atm) and temperature". Thus,

1 cubic meter of H2 at STP - 4500 Watt-hours

[Old Man]


I appreciate your response. Thanks.

Bob

Old Man wrote:

The number of hydrogen molecules (N, in moles) depends
upon gas pressure (P), temperature (T), and volume (V):


P * V = N * R * T or N = ( P * V ) / ( R * T )

NM3 probably means 'a cubic meter of hydrogen at standard
pressure (1 atm) and temperature". Thus,

1 cubic meter of H2 at STP - 4500 Watt-hours

[Old Man]


Curious, that's what... half the watt-hours in a gallon of gas?

Once I calculated how much energy a 6" diameter 24" long cylinder could hold
of H2 at 600PSI. This was to power a full-scale glider's electric motor (30HP)
for launch and climb. I forget the exact numbers but the end result was "this is
totally not feasible."

"Mark Jones" wrote in message
...
Curious, that's what... half the watt-hours in a gallon of gas?

Once I calculated how much energy a 6" diameter 24" long cylinder could
hold
of H2 at 600PSI. This was to power a full-scale glider's electric motor
(30HP)
for launch and climb. I forget the exact numbers but the end result was
"this is
totally not feasible."

I believe this is the current problem with hydrogen... how to store enough
of it in a car to give acceptable range.

From..

http://www.rps.psu.edu/hydrogen/form.html

"The problem, explains Eklund, is that "when it comes to energy density,
gasoline blows hydrogen away." While hydrogen packs more energy per pound
than gasoline - roughly three times more - it fills four times the space. To
visualize: A standard 15-gallon fuel tank holds about 90 pounds of gasoline.
To get the same amount of energy from hydrogen, you'd only need about 34
pounds of fuel, but holding it would take a 60-gallon tank.

Most prototype hydrogen-powered vehicles solve the problem by using
high-pressure tanks. The Toyota SUV that appeared on Penn State's campus
during Hydrogen Day last November carried two such tanks in its trunk, each
filled at 5,000 pounds per square inch. But safety and space remain
significant concerns, says Eklund. Even tanks of compressed hydrogen are big
and bulky. And, "if you puncture one of those compressed tanks, you release
a lot of gas in a hurry."
Other hydrogen-powered cars, like the newest BMW model, store hydrogen as a
liquid in super-cooled tanks nestled near the driver's seat. Cooling the
hydrogen increases its density, but a tremendous amount of energy is
required both to keep the tanks cold and, when needed, to turn the liquid
back into a gas that can be delivered to an engine or fuel cell.

"CWatters" wrote in message ...
|
| "Mark Jones" wrote in message
| ...
| Curious, that's what... half the watt-hours in a gallon of gas?
|
| Once I calculated how much energy a 6" diameter 24" long cylinder could
| hold
| of H2 at 600PSI. This was to power a full-scale glider's electric motor
| (30HP)
| for launch and climb. I forget the exact numbers but the end result was
| "this is
| totally not feasible."
|
| I believe this is the current problem with hydrogen... how to store enough
| of it in a car to give acceptable range.
|
| From..
|
| http://www.rps.psu.edu/hydrogen/form.html
|
| "The problem, explains Eklund, is that "when it comes to energy density,
| gasoline blows hydrogen away." While hydrogen packs more energy per pound
| than gasoline - roughly three times more - it fills four times the space. To
| visualize: A standard 15-gallon fuel tank holds about 90 pounds of gasoline.
| To get the same amount of energy from hydrogen, you'd only need about 34
| pounds of fuel, but holding it would take a 60-gallon tank.

That's acceptable for a host of applications, including the toilet facilities of a
Greyhound bus and the sleeping quarters of a Mack truck. If the average car owner has to give up some space on the roof or in the boot (trunk), so what?
If he doesn't like it, let him fill up more often.

|
| Most prototype hydrogen-powered vehicles solve the problem by using
| high-pressure tanks. The Toyota SUV that appeared on Penn State's campus
| during Hydrogen Day last November carried two such tanks in its trunk, each
| filled at 5,000 pounds per square inch. But safety and space remain
| significant concerns, says Eklund. Even tanks of compressed hydrogen are big
| and bulky. And, "if you puncture one of those compressed tanks, you release
| a lot of gas in a hurry."

Sure. Gas tanks explode too. People always take risk when dealing with
large quantities of energy, they die every day in traffic accidents. Being
shot out of the sky tends to be fatal too. What we always do is assess
risk of danger against convenience and cost, and have done so since the first human built a fire to cook food and keep warm or mounted a horse.

| Other hydrogen-powered cars, like the newest BMW model, store hydrogen as a
| liquid in super-cooled tanks nestled near the driver's seat. Cooling the
| hydrogen increases its density, but a tremendous amount of energy is
| required both to keep the tanks cold and, when needed, to turn the liquid
| back into a gas that can be delivered to an engine or fuel cell.

Technology will solve the problems because it has to. Even if you can't see
the solution at this moment, some bright spark will think of something
you have not considered and get rich. We've been to the Moon when the naysayers said it was not possible. We'll go to Mars, and we'll have hydrogen powered cars, just as long as you don't let women spend the entire budget
on cosmetics to attract a mate while bitching about what the "government" ought to do. We should never have given them the vote. China will be the world's strongest economy in twenty years, fueled by coal while Florida
sinks beneath the waves as Antarctica melts.
Androcles.

Only a small portion of Antarctica is melting - most of it is growing ice.
China is a flash in the pan economically - growing too big & too fast to
sustain itself. It's internal corruption, pollution, state sponsored
murder, imperialist dreams, strife, human rights problems - COMMUNISM
ITSELF - will keep it from ever surpassiing the US.


"Androcles" Androcles@ MyPlace.org wrote in message
.uk...

"CWatters" wrote in message
...
|
| "Mark Jones" wrote in message
| ...
| Curious, that's what... half the watt-hours in a gallon of gas?
|
| Once I calculated how much energy a 6" diameter 24" long cylinder
could
| hold
| of H2 at 600PSI. This was to power a full-scale glider's electric motor
| (30HP)
| for launch and climb. I forget the exact numbers but the end result was
| "this is
| totally not feasible."
|
| I believe this is the current problem with hydrogen... how to store enough
| of it in a car to give acceptable range.
|
| From..
|
| http://www.rps.psu.edu/hydrogen/form.html
|
| "The problem, explains Eklund, is that "when it comes to energy density,
| gasoline blows hydrogen away." While hydrogen packs more energy per pound
| than gasoline - roughly three times more - it fills four times the space.
To
| visualize: A standard 15-gallon fuel tank holds about 90 pounds of
gasoline.
| To get the same amount of energy from hydrogen, you'd only need about 34
| pounds of fuel, but holding it would take a 60-gallon tank.

That's acceptable for a host of applications, including the toilet
facilities of a
Greyhound bus and the sleeping quarters of a Mack truck. If the average car
owner has to give up some space on the roof or in the boot (trunk), so what?
If he doesn't like it, let him fill up more often.

|
| Most prototype hydrogen-powered vehicles solve the problem by using
| high-pressure tanks. The Toyota SUV that appeared on Penn State's campus
| during Hydrogen Day last November carried two such tanks in its trunk,
each
| filled at 5,000 pounds per square inch. But safety and space remain
| significant concerns, says Eklund. Even tanks of compressed hydrogen are
big
| and bulky. And, "if you puncture one of those compressed tanks, you
release
| a lot of gas in a hurry."

Sure. Gas tanks explode too. People always take risk when dealing with
large quantities of energy, they die every day in traffic accidents. Being
shot out of the sky tends to be fatal too. What we always do is assess
risk of danger against convenience and cost, and have done so since the
first human built a fire to cook food and keep warm or mounted a horse.

| Other hydrogen-powered cars, like the newest BMW model, store hydrogen as
a
| liquid in super-cooled tanks nestled near the driver's seat. Cooling the
| hydrogen increases its density, but a tremendous amount of energy is
| required both to keep the tanks cold and, when needed, to turn the liquid
| back into a gas that can be delivered to an engine or fuel cell.

Technology will solve the problems because it has to. Even if you can't see
the solution at this moment, some bright spark will think of something
you have not considered and get rich. We've been to the Moon when the
naysayers said it was not possible. We'll go to Mars, and we'll have
hydrogen powered cars, just as long as you don't let women spend the entire
budget
on cosmetics to attract a mate while bitching about what the "government"
ought to do. We should never have given them the vote. China will be the
world's strongest economy in twenty years, fueled by coal while Florida
sinks beneath the waves as Antarctica melts.
Androcles.

"Bob" wrote in message
. ..
Only a small portion of Antarctica is melting - most of it is growing ice.

...but the overall effect is a net loss.

China is a flash in the pan economically - growing too big & too fast to
sustain itself.

Well I wouldn't bet our future on that.