have blue
 

JAXAshby wrote:

oh, I see why you didn't understand. you didn't know that watts = hp. such a
pity.

Very good Jax, write that watts = hp-hrs in one post, then write that watts = hp
in another when it's pointed out to you that watts and hp are both units of power,
brilliant, absolutely brilliant.

Cheers
Marty

have blue
 

JAXAshby wrote:

didn't make it to fuel cells at this point, though it has been "nearly here"
for a couple decades.

If it works so extremely well for heavy, small volume welding bottle tanks why
hasn't it caught in the much more profitable market of fuel cells?


I believe the poblem lies in the rate at which the gas can be extracted/stored,
this is a function of the surface area of the hydride, for large fuel cells used for
transportation functions you can't get enough gas to feed the fuel cell during periods
of heavy demand.

Cheers
Marty

have blue
 

but still ... 5 hp drag on the boat. that is a lot.

The was with a 47 foot, 20,000 pound catamaran doing over 9 knots in a 20+
breeze, with two of the 12hp electric wheels. Your mileage may vary.


"Martin Baxter" wrote in message
...
Jeff Morris wrote:
Being a little sloppy with the units is not that bad - his real blunder
is
claiming 72 Watts output. The Condor catamaran claims 22 Amps at 144
Volts,
or
over 3 kW output when regenerating in a good breeze. They generate
enough
sailing during the day to power in and out of their inlet.


I'm still pretty skeptical, 3 kW is neary 5 Hp, allowing for some losses
it's going to be equivalent to stapping a 5 horse outboard to your bow
and run it full throttle trying to push the boat back. This might have
a significant impact on performance, speed wise, no?

Cheers
Marty

have blue
 

hey dum-dum, the context was clearly watts for hours, and compared to hp for
hours.

what word didn't you understand?

Very good Jax, write that watts = hp-hrs in one post, then write that watts =
hp
in another when it's pointed out to you that watts and hp are both units of
power,
brilliant, absolutely brilliant.

Cheers
Marty

have blue
 

Jaxie, you're having your typical comprehension problem. The 32 hp-hours
generated should be enough for an hour or two of powering - plenty to power the
cat out and back into the inlet. Since the batteries give 2 to 4 hours of
backup, it isn't really necessary to regenerate if you're day sailing out of a
slip.

If you want to do long distance powering or motorsailing, you need to run a
genset. However, a genset run at optimum rpm for recharging will be a lot
cheaper to run than twin diesels.

"JAXAshby" wrote in message
...
let's see. 22 amps at 144 (sic) volts when sailing 18 knots, for about 4 hp
stored per hour times 8 hours gives about 32 hp hours.

yup, that works. you sailed 144 miles and now you're going to motor back
using
1 hp and you are going to do it in just 32 hours (actually about 20 hours
after
taking out ineffiencies).

Being a little sloppy with the units is not that bad - his real blunder is
claiming 72 Watts output. The Condor catamaran claims 22 Amps at 144 Volts,
or
over 3 kW output when regenerating in a good breeze. They generate enough
sailing during the day to power in and out of their inlet.


"Martin Baxter" wrote in message
...
JAXAshby wrote:
oh, you mean horsepower can not be compared to watts?

Gee, the European engine manufacturers do it all the time. somebody
should
tell them you can't do that.

No, I mean this:

"6 amps at 12 volts for 24 hours = 1,728 watts, which = 2.3 hp-hours."

Amps times Volts times hours = Watt-hrs, a unit of energy
Horspower times hours= hp-hrs, a unit of energy
Watts are units of power
Horsepower is a unit of power (who would of thought it?)

Energy and power are two different things, which you well know.

Cheers
Marty

have blue
 

JAXAshby wrote:

hey dum-dum, the context was clearly watts for hours, and compared to hp for
hours.

what word didn't you understand?



Jax you would appear less of an idiot if you would learn to "Oops,
I made a small error" once in while.

I was you who wrote out a somewhat garble expression which had energy
on one side of an equals sign and power on the other, context has nothing to
do with it.

I'll post your words again so you can read them slowly:

"6 amps at 12 volts for 24 hours = 1,728 watts, which = 2.3 hp-hours"

This statement is quite unequivical, it first states that the product of
current and volts and time is watts, wrong; it then states that watts are
equivelent to hp-hours (assuming a conversion factor), also wrong.

Cheers
Marty

have blue
 

ah, I see your problem now. when you read 1,728 watts stored you didn't
realize that if you took that energy back out you could get 2.3 hp back out for
one hour, or 0.23 hp for 10 hours, or 0.0023 hp for a thousand hours or 23 hp
for six minutes or 230 hp for 36 seconds, or 2300 hp for 3.6 seconds or 23000
hp for about 1/3 second.

All less inefficiencies, of course.

bax, you need to read more slowly, paying particular attention to content.

I'll post your words again so you can read them slowly:

"6 amps at 12 volts for 24 hours = 1,728 watts, which = 2.3 hp-hours"

This statement is quite unequivical, it first states that the product of
current and volts and time is watts, wrong; it then states that watts are
equivelent to hp-hours (assuming a conversion factor), also wrong.

Cheers
Marty

have blue
 

so, the regen doesn't really work unless you plug the batteries in at the dock?

okay.

but, if that is the case why buy the regen equipment?


Jaxie, you're having your typical comprehension problem. The 32 hp-hours
generated should be enough for an hour or two of powering - plenty to power
the
cat out and back into the inlet. Since the batteries give 2 to 4 hours of
backup, it isn't really necessary to regenerate if you're day sailing out of
a
slip.

If you want to do long distance powering or motorsailing, you need to run a
genset. However, a genset run at optimum rpm for recharging will be a lot
cheaper to run than twin diesels.

"JAXAshby" wrote in message
...
let's see. 22 amps at 144 (sic) volts when sailing 18 knots, for about 4
hp
stored per hour times 8 hours gives about 32 hp hours.

yup, that works. you sailed 144 miles and now you're going to motor back
using
1 hp and you are going to do it in just 32 hours (actually about 20 hours
after
taking out ineffiencies).

Being a little sloppy with the units is not that bad - his real blunder is
claiming 72 Watts output. The Condor catamaran claims 22 Amps at 144
Volts,
or
over 3 kW output when regenerating in a good breeze. They generate enough
sailing during the day to power in and out of their inlet.


"Martin Baxter" wrote in message
...
JAXAshby wrote:
oh, you mean horsepower can not be compared to watts?

Gee, the European engine manufacturers do it all the time. somebody
should
tell them you can't do that.

No, I mean this:

"6 amps at 12 volts for 24 hours = 1,728 watts, which = 2.3 hp-hours."

Amps times Volts times hours = Watt-hrs, a unit of energy
Horspower times hours= hp-hrs, a unit of energy
Watts are units of power
Horsepower is a unit of power (who would of thought it?)

Energy and power are two different things, which you well know.

Cheers
Marty

have blue
 

I thought also the "energy density" was much worse as compared to gasoline.

I believe the poblem lies in the rate at which the gas can be
extracted/stored,
this is a function of the surface area of the hydride, for large fuel cells
used for
transportation functions you can't get enough gas to feed the fuel cell
during periods
of heavy demand.

Cheers
Marty

have blue
 

sounds like too long jax, re-do your math. Take a couple days, then get
back to us.

SV


"JAXAshby" wrote

AND if you are willing to sail for 173 days straight just to motor less
than a
day. (see prior post).