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-   -   fuel cell battery buffer or cap? (https://www.radiobanter.com/antenna/107911-fuel-cell-battery-buffer-cap.html)

ml October 26th 06 01:22 AM

fuel cell battery buffer or cap?
 
hi

was wondering if someone had some thoughts on this and might be able to
help me 'calculate' the value i need

I was thinking of getting a jado fuel cell, it puts out 100w (about
8amps ?) @12vdc

it's not totally regulated, at full output the volts dip a bit

wanted to power a 2m rig at low power 5w out it falls w/in the spec's
of the jado but i wanted a buffer

at first i thought of a battery using the full cell to charge the
battery during receive since tx is brief but how do i calculate
how big a battery i need?


i also wondering if perhaps a capacitor or a few of them might also
do the trick and if so how to size them

not sure the pro's /cons' of battery vs cap's


naturally if i used the caps' i'd prob get a dc to dc regulator

any help appreciated

Richard Clark October 26th 06 01:50 AM

fuel cell battery buffer or cap?
 
On Thu, 26 Oct 2006 00:22:01 GMT, ml wrote:

I was thinking of getting a jado fuel cell, it puts out 100w (about
8amps ?) @12vdc


Hi Myles,

Fuel Cell??? That is a pretty pricey option.

More than likely it is 100WH (Watt-hour, not Watt) rated.

wanted to power a 2m rig at low power 5w out it falls w/in the spec's
of the jado but i wanted a buffer


Well, a 5W transmitter is not going to load it too heavily, but you
have to figure that 5W out is a 10W demand on the battery. This means
your battery will work 8 - 10 Hours continuous (you don't sit on the
key, do you?).

at first i thought of a battery using the full cell to charge the
battery during receive since tx is brief but how do i calculate


A battery - fuel cell - battery?

how big a battery i need?


At least 100WH, undoubtedly more.

Why charge a fuel cell with a battery? Why not cut out the middle man
and just run battery operation?

i also wondering if perhaps a capacitor or a few of them might also
do the trick and if so how to size them


Not unless you can assemble a couple hundred Farads (note the complete
absence of pico, nano, or micro in that Farads). The short version is
DON'T GO THERE.

73's
Richard Clark, KB7QHC

Tom Ring October 26th 06 02:27 AM

fuel cell battery buffer or cap?
 
ml wrote:

hi

was wondering if someone had some thoughts on this and might be able to
help me 'calculate' the value i need

I was thinking of getting a jado fuel cell, it puts out 100w (about
8amps ?) @12vdc

it's not totally regulated, at full output the volts dip a bit

wanted to power a 2m rig at low power 5w out it falls w/in the spec's
of the jado but i wanted a buffer

at first i thought of a battery using the full cell to charge the
battery during receive since tx is brief but how do i calculate
how big a battery i need?


i also wondering if perhaps a capacitor or a few of them might also
do the trick and if so how to size them

not sure the pro's /cons' of battery vs cap's


naturally if i used the caps' i'd prob get a dc to dc regulator

any help appreciated


I would use a small gel cell across the 12V output. I do have some
worries since it says "nominal" 12V output and no better information
than that seems to be available on the site.

Except the prices. You must be quite well off to consider purchasing
this, since the XRT is $7999 and does not include a refill station at
$599 or $1799, so once your canisters are empty you are done.

If you can afford this system, I would suggest you buy a nice top end
deep cycle battery, $300 for 80 AH is in the correct range.

Or you could just burn gasoline in a 2000W Honda which costs about
$1000, makes almost no noise, is quite light, and will generate less CO2
than the fuel cell system will when you get down to reality since the
fuel cell system is actually powered by the fairly inefficient
electrical grid. And it will cost a ton less as well as delivering 20
times the peak power with commonly available fuel.

tom
K0TAR

Cecil Moore October 26th 06 02:34 AM

fuel cell battery buffer or cap?
 
Tom Ring wrote:
If you can afford this system, I would suggest you buy a nice top end
deep cycle battery, $300 for 80 AH is in the correct range.


My 115 amp hour deep cycle trolling battery only
cost about $70 at Sam's Club.
--
73, Cecil http://www.w5dxp.com

Tom Ring October 26th 06 03:38 AM

fuel cell battery buffer or cap?
 
Tom Ring wrote:

Or you could just burn gasoline in a 2000W Honda which costs about
$1000, makes almost no noise, is quite light, and will generate less CO2
than the fuel cell system will when you get down to reality since the
fuel cell system is actually powered by the fairly inefficient
electrical grid. And it will cost a ton less as well as delivering 20
times the peak power with commonly available fuel.


BTW, the 1000W EU1000i model will deliver 1000W at 3.8 gallons per day,
and 250W at 1.7 gallons per day. The unit is listed at 790 USD. There
are simple modifications to use a boat gas tank (usually about 6
gallons) with this unit which would make the run time 3 days for most
emergency amateur use before refill. I would take this as a first
responder system in a heartbeat.

I also wonder where one would get the energy to refill the hydrogen for
the fuel cell unit when in a place like New Orleans after Katrina.
Gasoline would still need to be hauled in, and would probably be more
efficiently used providing power directly from a smart generator than
splitting water to make hydrogen which would then be used in a fuel cell.

tom
K0TAR


Tom Ring October 26th 06 04:25 AM

fuel cell battery buffer or cap?
 
ml wrote:

hi

was wondering if someone had some thoughts on this and might be able to
help me 'calculate' the value i need

I was thinking of getting a jado fuel cell, it puts out 100w (about
8amps ?) @12vdc

it's not totally regulated, at full output the volts dip a bit

wanted to power a 2m rig at low power 5w out it falls w/in the spec's
of the jado but i wanted a buffer

at first i thought of a battery using the full cell to charge the
battery during receive since tx is brief but how do i calculate
how big a battery i need?


i also wondering if perhaps a capacitor or a few of them might also
do the trick and if so how to size them

not sure the pro's /cons' of battery vs cap's


naturally if i used the caps' i'd prob get a dc to dc regulator

any help appreciated


If all you really need is 5W out I would spend my money on about 5 amps
of solar cells at 12 volts nominal, a really good charge controller such
as this one - http://store.solar-electric.com/sbchco2512vm.html - and a
good 200 or 300 AH deep cycle, you would be well ahead of the fuel cell
solution. And it would keep you in energy for a lot of dim days.

tom
K0TAR


ml October 26th 06 10:37 AM

Gang fuel cell battery buffer or cap?
 
In article ,
Richard Clark wrote:

On Thu, 26 Oct 2006 00:22:01 GMT, ml wrote:

I was thinking of getting a jado fuel cell, it puts out 100w (about
8amps ?) @12vdc


Hi Myles,

Fuel Cell??? That is a pretty pricey option.

More than likely it is 100WH (Watt-hour, not Watt) rated.

wanted to power a 2m rig at low power 5w out it falls w/in the spec's
of the jado but i wanted a buffer


Well, a 5W transmitter is not going to load it too heavily, but you
have to figure that 5W out is a 10W demand on the battery. This means
your battery will work 8 - 10 Hours continuous (you don't sit on the
key, do you?).

at first i thought of a battery using the full cell to charge the
battery during receive since tx is brief but how do i calculate


A battery - fuel cell - battery?

how big a battery i need?


At least 100WH, undoubtedly more.

Why charge a fuel cell with a battery? Why not cut out the middle man
and just run battery operation?

i also wondering if perhaps a capacitor or a few of them might also
do the trick and if so how to size them


Not unless you can assemble a couple hundred Farads (note the complete
absence of pico, nano, or micro in that Farads). The short version is
DON'T GO THERE.

73's
Richard Clark, KB7QHC


thanks to all that replyed\
Tom , you changed my equation, combustion generators and solar are not
options or the question, it was a rather obvious choice but thanks
not sure where everyone got their spec's from and pricing but your
numbers are off and most likely i'd get a sample unit free , tom i
also wouldn't be using it's charging canisters but sstraight into the
tank

the jado i mentioned list price is around 2k$$ and i can get it for
less list and it is 100w it lit my 75w light bulb pretty steady and
bright

Question:
i thought since my key down isn't steady that might be enough juice to
then charge top off'' the battery but i didn't know how to size it

i'd have x amps (or ah) from fuel cell x ammount of draw think my rig
pulls 5amps? tx, x ammount capacity from batt,, so after say a min of
key down the battery would be y drained, given a big enough battery
Y (drain)would need to be small enough such that the 12/8amps out of the
Jado fuel cell would be able /fast enough to top it back off

question is what is that value how do i calculate how big a battery i
need at the know constants?



Rich the reason i thought of cap's was both the short key down time and
the article in cq of this new powersupply that uses a few 5farads it
got me thinking if it could be modified to do dc to dc regulation
rather than 120v ....maybe i was pushing it, then i thought of
supercapacitors i dunno

Tom Ring October 26th 06 01:50 PM

Gang fuel cell battery buffer or cap?
 
ml wrote:


question is what is that value how do i calculate how big a battery i
need at the know constants?



Rich the reason i thought of cap's was both the short key down time and
the article in cq of this new powersupply that uses a few 5farads it
got me thinking if it could be modified to do dc to dc regulation
rather than 120v ....maybe i was pushing it, then i thought of
supercapacitors i dunno


I got the pricing from jadoo's site for the unit plus 6 container combo.
And you will still need something to refill.

On the battery, when we used to VHF contest with a light (600W)
generator and power supplies, we would put a 25AH battery across each 15
amp supply and we could draw 40 or 50 amps on CW/SSB peaks with no
issues. So you would probably be well served by one of the 7AH UPS
batteries from a place such as Batteries Plus. They cost about $25 and
are about 7"Lx2"Wx4"H.

tom
K0TAR

Jim Kelley October 26th 06 04:53 PM

fuel cell battery buffer or cap?
 


Richard Clark wrote:

Hi Myles,

Fuel Cell??? That is a pretty pricey option.

More than likely it is 100WH (Watt-hour, not Watt) rated.


https://jadoopower.com/fuel_cell.html






Richard Clark October 26th 06 06:01 PM

fuel cell battery buffer or cap?
 
On Thu, 26 Oct 2006 08:53:31 -0700, Jim Kelley
wrote:



Richard Clark wrote:

Hi Myles,

Fuel Cell??? That is a pretty pricey option.

More than likely it is 100WH (Watt-hour, not Watt) rated.


https://jadoopower.com/fuel_cell.html


Which reports:
Output: 12 VDC Nominal
Wattage: 100 W Continuous

WOW! Infinite Watt Hours. I think we can walk away from the mid-east
right now.

Richard Clark October 26th 06 06:14 PM

Gang fuel cell battery buffer or cap?
 
On Thu, 26 Oct 2006 09:37:27 GMT, ml wrote:

question is what is that value how do i calculate how big a battery i
need at the know constants?


Hi Myles,

It is a matter of three things:
1. Amp-Hour or Watt-Hour capacity;
2. Demand for Amps or Watts;
3. Duty ratio.

Based on your specification for a 5W rig (I assume it is a hand held,
a small mobile would be more like 20-35W) and an efficiency during
transmit of 50-70%, then your demand would be at least 10W during
transmit. Receive would require some baseline power, my guess would
be 2W, maybe less. If you listen more than you talk by a factor of 5,
then you could count on an average demand of 2W.

Divide this 2W into the Watt-Hour capacity (I will assume 100WH) and
your power source should last two days continuous use (do you plan on
sleeping?) or 50 hours of on time over any more extended period. That
is, if you sleep 12 hours, you can stretch the service time out to 4
days. If you operate only 2 hours a day, you can stretch the service
time out over a month an a half.

73's
Richard Clark, KB7QHC

Jim Kelley October 26th 06 06:54 PM

fuel cell battery buffer or cap?
 
Richard Clark wrote:
On Thu, 26 Oct 2006 08:53:31 -0700, Jim Kelley
wrote:

Richard Clark wrote:


Hi Myles,

Fuel Cell??? That is a pretty pricey option.

More than likely it is 100WH (Watt-hour, not Watt) rated.


https://jadoopower.com/fuel_cell.html



Which reports:
Output: 12 VDC Nominal
Wattage: 100 W Continuous


So apparently your correspondent was correct after all.

WOW! Infinite Watt Hours. I think we can walk away from the mid-east
right now.


No, actually when you take time to understand the literature (like
Myles evidently has), it becomes quite clear that the limit to the
rate at which energy can be extracted from the power unit is 100
watts, and that the total amount of energy which can be extracted is
determined by the capacity of the fuel cannister; either 130
watt-hours or 360 watt-hours.

So it seems that if you want to be able to rely on this power source
for any extended length of time, 5 watts would not be an unreasonable
load. I'll wager it would even count for 100 extra points at Field
Day - albeit at a cost of $15-$20 a point.

73, Jim AC6XG


Jim - NN7K October 26th 06 10:20 PM

Gang fuel cell battery buffer or cap?
 
Always wanted a 1 FARAD (or bigger) capacitor!
Where can you buy one?? (Short of buying a
"Charged "one, I.E. Storage Battery)? Oh
well only 6 Months to April First!
Jim NN7K


Richard Clark wrote:




Not unless you can assemble a couple hundred Farads (note the complete
absence of pico, nano, or micro in that Farads). The short version is
DON'T GO THERE.

73's
Richard Clark, KB7QHC


David Hatch October 26th 06 10:31 PM

Gang fuel cell battery buffer or cap?
 
Jim - NN7K wrote in QE90h.22140$e66.18599
@newssvr13.news.prodigy.com:

Always wanted a 1 FARAD (or bigger) capacitor!
Where can you buy one??


Try your local car stereo place. About the size of a tennis ball can.
Best Buy has some on their website. Search for capacitor.

--
David
KR7DH

Jim Kelley October 26th 06 10:56 PM

Gang fuel cell battery buffer or cap?
 


Jim - NN7K wrote:
Always wanted a 1 FARAD (or bigger) capacitor!
Where can you buy one?? (Short of buying a
"Charged "one, I.E. Storage Battery)? Oh
well only 6 Months to April First!
Jim NN7K


http://www.radioshack.com/search/ind...ad%20capacitor


73, Jim AC6XG


Richard Clark October 26th 06 11:02 PM

Gang fuel cell battery buffer or cap?
 
On Thu, 26 Oct 2006 21:20:48 GMT, Jim - NN7K wrote:

Always wanted a 1 FARAD (or bigger) capacitor!
Where can you buy one?? (Short of buying a
"Charged "one, I.E. Storage Battery)? Oh
well only 6 Months to April First!


Hi Jim,

1 FARAD (or bigger) capacitors have been around for YEARS. Go to any
Hi-Fi shop and spend as much as you want. Be warned that cost is
proportional to breakdown voltage rating.

Or try:
http://www.hobbyengineering.com/Sect...tml#CatPSSUPER

73's
Richard Clark, KB7QHC

[email protected] October 26th 06 11:15 PM

Gang fuel cell battery buffer or cap?
 
Jim - NN7K wrote:
Always wanted a 1 FARAD (or bigger) capacitor!
Where can you buy one?? (Short of buying a
"Charged "one, I.E. Storage Battery)? Oh
well only 6 Months to April First!
Jim NN7K



Richard Clark wrote:




Not unless you can assemble a couple hundred Farads (note the complete
absence of pico, nano, or micro in that Farads). The short version is
DON'T GO THERE.

73's
Richard Clark, KB7QHC


Why settle for a measly 1 F when you can have 50 F?

Go to www.digikey.com and search for 283-2511-ND.

--
Jim Pennino

Remove .spam.sux to reply.

Richard Clark October 26th 06 11:26 PM

Gang fuel cell battery buffer or cap?
 
On Thu, 26 Oct 2006 15:02:55 -0700, Richard Clark
wrote:

Or try:
http://www.hobbyengineering.com/Sect...tml#CatPSSUPER


Or for up to 50F for less than 50 Cents a Farad:

http://www.newark.com/NewarkWebComme...comSearch=true

Interesting to note this one of the few, practical (meaning making
money in a commercial market) Nanotech applications of an aerogel.

73's
Richard Clark, KB7QHC

ml October 27th 06 12:37 AM

calculations/ fuel cell battery buffer or cap?
 
In article ,
Tom Ring wrote:

ml wrote:


question is what is that value how do i calculate how big a battery i
need at the know constants?



Rich the reason i thought of cap's was both the short key down time and
the article in cq of this new powersupply that uses a few 5farads it
got me thinking if it could be modified to do dc to dc regulation
rather than 120v ....maybe i was pushing it, then i thought of
supercapacitors i dunno


I got the pricing from jadoo's site for the unit plus 6 container combo.
And you will still need something to refill.

On the battery, when we used to VHF contest with a light (600W)
generator and power supplies, we would put a 25AH battery across each 15
amp supply and we could draw 40 or 50 amps on CW/SSB peaks with no
issues. So you would probably be well served by one of the 7AH UPS
batteries from a place such as Batteries Plus. They cost about $25 and
are about 7"Lx2"Wx4"H.

tom
K0TAR


gosh, i sure do appreciate everybody's help, sincerely, but alas, i
still have no concise way to calculate what size battery or cap i need

but i can add a few things, even thou it's sorta a different topic
many here seem concerned about the size of the canisters and refilling
them, this is not a concern as the unit will be feed directly off a
large Hydrogen tank, not the little canisters i do not need to
calculate how long the unit(jado) will run at load vs fuel supply this
is already a known constant and published thats the easy part

the unit does 12v unregulated at about 7amps if you hit 7amps for long
voltage goes down to 10v so i will add some regulator if needed

when i said my radio(2m mobile) will be ""putting out 5w on low pwr""
i ment 5w rf output not current draw sorry

so rich since your calculation was for ah what would it be for for
the correct above spec's?? amps or 100w (no ah)?

i would have to have a battery big enough to be -drained little enough
so that the jado would be able to recharge it during the rx time(least
load) from what tx drained the battery obv if the battery is too
big then the jado wouldn't be able to recharge it or float it

right now i have 2 G27(parallel) and i float them at less than 1amp

naturally when i say recharge i don't mean from anything other than a
slight drain as in normal tx /rx

so the question become how do i calculate that? and would a ultra cap
fit in ?

i thought it would be kinda simple, gut wise i can guess but what i
was hoping for here was a more precise calculation of what would do
the trick

again thanks all for taking the time to respond , i always learn
something


ml

Tom Ring October 27th 06 01:18 AM

Gang fuel cell battery buffer or cap?
 
Jim - NN7K wrote:

Always wanted a 1 FARAD (or bigger) capacitor!
Where can you buy one?? (Short of buying a
"Charged "one, I.E. Storage Battery)? Oh
well only 6 Months to April First!
Jim NN7K


Check with your local high power car audio shop. They carry them.

I have one, but it's only half a farad at 30 volts.

tom
K0TAR

Jim Kelley October 27th 06 01:55 AM

calculations/ fuel cell battery buffer or cap?
 
ml wrote:

gosh, i sure do appreciate everybody's help, sincerely, but alas, i
still have no concise way to calculate what size battery or cap i need


Please pardon the dumb question, but if you have a 100 watt fuel cell
why do you need a battery?

73, Jim AC6XG


Tom Ring October 27th 06 02:05 AM

calculations/ fuel cell battery buffer or cap?
 
ml wrote:

issues. So you would probably be well served by one of the 7AH UPS
batteries from a place such as Batteries Plus. They cost about $25 and
are about 7"Lx2"Wx4"H.

tom
K0TAR



gosh, i sure do appreciate everybody's help, sincerely, but alas, i
still have no concise way to calculate what size battery or cap i need


I thought my statement was clear, but I will repeat it -

"So you would probably be well served by one of the 7AH UPS batteries
from a place such as Batteries Plus. They cost about $25 and are about
7"Lx2"Wx4"H." Float that across your fuel cell and you will be fine.

Of course, if the fuel cell doesn't put out at least 13.5 vclts with
your rig on receive, a "12 volt" float battery won't have enough charge
in it to speak of. Then it would be back to capacitors and the
interesting problem that they would bring along. Such as a 0 volt
charge current that could possibly be damaging to your fuel cell.

This whole thing seems a very expensive way to have not very good
portable power. You have never stated why you must have a fuel cell.
Would you care to enlighten us?

tom
K0TAR

K7ITM October 27th 06 02:06 AM

Gang fuel cell battery buffer or cap?
 

wrote:
Jim - NN7K wrote:
Always wanted a 1 FARAD (or bigger) capacitor!
Where can you buy one?? (Short of buying a
"Charged "one, I.E. Storage Battery)? Oh
well only 6 Months to April First!
Jim NN7K



Richard Clark wrote:




Not unless you can assemble a couple hundred Farads (note the complete
absence of pico, nano, or micro in that Farads). The short version is
DON'T GO THERE.

73's
Richard Clark, KB7QHC


Why settle for a measly 1 F when you can have 50 F?

Go to
www.digikey.com and search for 283-2511-ND.

--
Jim Pennino

Remove .spam.sux to reply.


And if the 5W output rig draws an amp on transmit, that 50F cap will
run it for 50 seconds with a one-volt drop. Compare that with an
inexpensive little 7Ah 12V gel-cell battery that will run it for
probably five hours. Caps may make sense to smooth over short pulses
of current, but seem like a poor solution for storing long-term energy.

The OP's question is so basic that I wonder if he's pulling our
collective legs.
--How many amps does the rig draw in transmit? In receive?
--How long do you want the aux power source to run it?
----how many hours of transmit; how many hours of receive?
--That tells you the minimum Ah rating for the aux battery.
--Use I = C * dV/dt and how much voltage drop you can stand
to figure the size capacitor you'd need to do the same thing
for an aux capacitor (and then discard the idea in favor of a
much cheaper battery).

Cheers,
Tom


ml October 27th 06 02:59 AM

ans calculations/ fuel cell battery buffer or cap?
 


I thought my statement was clear, but I will repeat it -

"So you would probably be well served by one of the 7AH UPS batteries
from a place such as Batteries Plus. They cost about $25 and are about
7"Lx2"Wx4"H." Float that across your fuel cell and you will be fine.

Of course, if the fuel cell doesn't put out at least 13.5 vclts with
your rig on receive, a "12 volt" float battery won't have enough charge
in it to speak of. Then it would be back to capacitors and the
interesting problem that they would bring along. Such as a 0 volt
charge current that could possibly be damaging to your fuel cell.

OK, that was clear, i sorta thought it seemed a bit small, and figured
you calculated at 100ah nnot 100w my bad

This whole thing seems a very expensive way to have not very good
portable power. You have never stated why you must have a fuel cell.
Would you care to enlighten us?

tom
K0TAR


well if one had to buy the jado it might be expensive, i can get one
much cheeper than list and somone here posted an incorrect list price
anyways , - then again if you add up the total cost of the
competition you'd at worst case be in the ball park

the goal was at first to power a hf/rig 100w tx for a few days on a
backup power source looking at batteries/fuelcells i realized this is to
much load so i figured my 2m righ on low pwr is a compramise @1week

at 100w tx, i started to put together on paper what i need, a pretty
big charger lots of very big heavy batteries , and they are VERY
expensive, if the batteries went 'low' and the power wasn't restored
say an extended blackout then the battery life goes down the tubes

now i live in an apt, so too many batteries even if free arent practical

code prevents me from using a generator in the building, so would the
coop board, and the noise, smell vibration and mostly a generator
running would attract 'undesiables' it would be kinda cheep and
storing say desil wouldn't be a big deal if say i had a pvt house
again thou getting extra fuel in a extended blackout would be an issue

i had a demo of this fuel cell i was really impressed, is the cost and
power output totally there no i guess not a few years from now prob
but the cost of the fuel cell unit alone is comparable to the battery
cost and i don't have to worry about the space, and other issues
associated w/batteries

i can get a small tank of hydrogen that would power the unit for longer
than i was planning for it's cheep and i can get it very easy even if
theyre was an extended blackout (details omitted) it's quite meets
code, very small, very light dosn't pollute or stink

seemed rather sexy the jado can also be powered from small cartridges
making the unit selfcontained and very portable, however this isn't a
requirement of mine but cool benni

the only con for me, seems to be a)not totally going to give me 100w
at full load b) i wish the unit was more than a puny 100w the larger
units i would have to pay full list for and are therefore outta reach


so solar /wind again might be nice in a pvt home but nothing i'd
rely on

it usually starts simple, i wanted somthing better than battery power

much appreciation
and mostly also because i like to tinker and learn seems like somthing
cool to play with and experiment

Tom Ring October 27th 06 04:04 AM

ans calculations/ fuel cell battery buffer or cap?
 
ml wrote:

well if one had to buy the jado it might be expensive, i can get one
much cheeper than list and somone here posted an incorrect list price
anyways , - then again if you add up the total cost of the
competition you'd at worst case be in the ball park

the goal was at first to power a hf/rig 100w tx for a few days on a
backup power source looking at batteries/fuelcells i realized this is to
much load so i figured my 2m righ on low pwr is a compramise @1week

at 100w tx, i started to put together on paper what i need, a pretty
big charger lots of very big heavy batteries , and they are VERY
expensive, if the batteries went 'low' and the power wasn't restored
say an extended blackout then the battery life goes down the tubes

now i live in an apt, so too many batteries even if free arent practical

code prevents me from using a generator in the building, so would the
coop board, and the noise, smell vibration and mostly a generator
running would attract 'undesiables' it would be kinda cheep and
storing say desil wouldn't be a big deal if say i had a pvt house
again thou getting extra fuel in a extended blackout would be an issue

i had a demo of this fuel cell i was really impressed, is the cost and
power output totally there no i guess not a few years from now prob
but the cost of the fuel cell unit alone is comparable to the battery
cost and i don't have to worry about the space, and other issues
associated w/batteries

i can get a small tank of hydrogen that would power the unit for longer
than i was planning for it's cheep and i can get it very easy even if
theyre was an extended blackout (details omitted) it's quite meets
code, very small, very light dosn't pollute or stink

seemed rather sexy the jado can also be powered from small cartridges
making the unit selfcontained and very portable, however this isn't a
requirement of mine but cool benni

the only con for me, seems to be a)not totally going to give me 100w
at full load b) i wish the unit was more than a puny 100w the larger
units i would have to pay full list for and are therefore outta reach


so solar /wind again might be nice in a pvt home but nothing i'd
rely on

it usually starts simple, i wanted somthing better than battery power

much appreciation
and mostly also because i like to tinker and learn seems like somthing
cool to play with and experiment


Ok, I have applied a simple power budget to what you stated your
original desire was, as opposed to your cut down 2m 5W system.

Using a rig I own, an FT-897, on HF.

Assume 90% receive at 1 amp.
Assume 10% transmit at 15 amps with 100 watts output, (measured as
opposed to the 22 amps claimed in the docs)

This gives 2.4 amps average consumption. (Check my math, the doctor did
a lot during my pre-op today)

1 week is 168 hours which gives us 403 ampere hours.

100AH deep cycle batteries are around 100 each (or less), So that's
about $400 for all the batteries you need for a week without sleep.

A modern top of the line charger, such as produced by Schumacher, is
less than $100, does automatic desulfation, will charge at 50 amps or
greater, and weighs about 6 pounds.

So now we are at under 500 dollars for an emergency power for any ham
that needs to run an HF rig for a whole week.

I just don't see why you want to use the fuel cell, it makes no sense.

tom
K0TAR

Roy Lewallen October 27th 06 05:06 AM

ans calculations/ fuel cell battery buffer or cap?
 
Tom Ring wrote:
. . .
1 week is 168 hours which gives us 403 ampere hours.
. . .


which at 13.6 volts is about 5480 watt-hours. This is the energy storage
requirement.

The OP asked about using a capacitor. The energy stored in a capacitor
is C * V^2 / 2. For capacitance in farads and voltage in volts, the
result is joules, or watt-seconds -- you need 5480 * 3600 ~ 20,000,000
joules in round numbers. So suppose you wanted to store this same amount
of energy in a capacitor, and you had a switching regulator which would
handle 50 volts maximum input voltage. Solving for C, assuming it's
charged to 50 volts,

C = 20,000,000 * 2 / (50^2) = 16,000 farads.

This assumes you can get all the energy out of the capacitor, which
requires your regulator to work down to zero volts. But you'll get 3/4
of the energy out of it if your regulator cuts off at 25 volts, 7/8 if
it cuts off at 12.5 volts, etc.

How does that sound?

Roy Lewallen, W7EL

ml October 27th 06 10:33 AM

cap/ ans calculations/ fuel cell battery buffer or cap?
 
In article ,
Roy Lewallen wrote:

Tom Ring wrote:
. . .
1 week is 168 hours which gives us 403 ampere hours.
. . .


which at 13.6 volts is about 5480 watt-hours. This is the energy storage
requirement.

The OP asked about using a capacitor. The energy stored in a capacitor
is C * V^2 / 2. For capacitance in farads and voltage in volts, the
result is joules, or watt-seconds -- you need 5480 * 3600 ~ 20,000,000
joules in round numbers. So suppose you wanted to store this same amount
of energy in a capacitor, and you had a switching regulator which would
handle 50 volts maximum input voltage. Solving for C, assuming it's
charged to 50 volts,

C = 20,000,000 * 2 / (50^2) = 16,000 farads.

This assumes you can get all the energy out of the capacitor, which
requires your regulator to work down to zero volts. But you'll get 3/4
of the energy out of it if your regulator cuts off at 25 volts, 7/8 if
it cuts off at 12.5 volts, etc.

How does that sound?

Roy Lewallen, W7EL


well i guess it sounds like i wont have any 16,000 farad cap's stacked
up in my myplace anytime soon, but i understand the math behind it
now thanks

perhaps i'll just get a small cap to handle a brief second keydown dip
smooth things out a bit

thanks

ml October 27th 06 11:01 AM

preop/ ans calculations/ fuel cell battery buffer or cap?
 
In article ,
Tom Ring wrote:

ml wrote:
omitted) it's quite meets
code, very small, very light dosn't pollute or stink

seemed rather sexy the jado can also be powered from small cartridges
making the unit selfcontained and very portable, however this isn't a
requirement of mine but cool benni

the only con for me, seems to be a)not totally going to give me 100w
at full load b) i wish the unit was more than a puny 100w the larger
units i would have to pay full list for and are therefore outta reach


so solath and experiment


Ok, I have applied a simple power budget to what you stated your
original desire was, as opposed to your cut down 2m 5W system.

Using a rig I own, an FT-897, on HF.

Assume 90% receive at 1 amp.
Assume 10% transmit at 15 amps with 100 watts output, (measured as
opposed to the 22 amps claimed in the docs)

This gives 2.4 amps average consumption. (Check my math, the doctor did
a lot during my pre-op today)

1 week is 168 hours which gives us 403 ampere hours.

100AH deep cycle batteries are around 100 each (or less), So that's
about $400 for all the batteries you need for a week without sleep.

A modern top of the line charger, such as produced by Schumacher, is
less than $100, does automatic desulfation, will charge at 50 amps or
greater, and weighs about 6 pounds.

So now we are at under 500 dollars for an emergency power for any ham
that needs to run an HF rig for a whole week.

I just don't see why you want to use the fuel cell, it makes no sense.

tom
K0TAR

tom, am i to understand you had some surgery today? if so, i hope all is
well with you and taking the time to write is appreciated

i am guessing roy's calculation of the total ampre hrs needed is closer
to being correct, but it's 5am and i kinda don't know how to calculate
that so i dunno as stated in my earlier post i don't have the formulas
so i can't act to confirm but i nod my head and presume it's all correct
based on roys math

you are correct about what the rig is doing mine is exactly simular i
would calculate based on 20amps

re your last comments on why i would want a fuel cell, it should be very
clear in all my many posts

5480 watt-hours of battery is more $$ and large than i have practical
room for

i can get the fuel cell for practically nothing and i just thought it
might be able to offer some useful power to top off a battery to
provide some b/u power why not? and also be a fun experiment it runs
quiet , clean and i can get all the fuel i want free always, i would
never be able to get fossel fuels in a blackout or other emerg

so now i inch a drop closer knowing how many what hours my original
abandoned goal would draw , however my current stated goal is to just
power my 5w tx output(draws4amps) 2m mobile rig

and try to calculate how much the battery would be drained in a 1min
tx and then see if the 12v 7amps comming out of the jado would recharge
it fast enough i believe that is what must be calculated for just not
sure how do it, unless you still say a 7amp battery is still 'ok'

my goal was to be able to calculate

so a 7amp battery(or what ever is needed optically this seems like a too
low a #)) w/a 1min 4amp load would be ??%drained
then based on manuf spec's for the battery we could calculate how much
power &time would be needed to top it back off

then it would be simple enough to see if the output of the jado is
sufficient i think thats all thats needed i think that's simple
but i dunno how to calculate it
thanks all i really wanted to do

Dave October 27th 06 12:29 PM

ans calculations/ fuel cell battery buffer or cap?
 

"ml" wrote in message
...

now i live in an apt, so too many batteries even if free arent practical

code prevents me from using a generator in the building, so would the
coop board, and the noise, smell vibration and mostly a generator
running would attract 'undesiables' it would be kinda cheep and
storing say desil wouldn't be a big deal if say i had a pvt house
again thou getting extra fuel in a extended blackout would be an issue


i bet you also find that storing explosive gasses in an apartment are also
against code. and laywers would probably consider a fuel cell a generator
also.

your best bet is to just keep a few gell cells around to run your vhf on low
power, you can get many hours on a charge... when one dies, swap for another
one, take it out to your car, charge it from there, and bring it back in.

remember, in an emergency you most likely won't be making long transmissions
anyway, first because there won't be that many locals to talk to because
most of them won't have power... repeaters will be tied up with emergency
traffic, and unless you are a net control you should mostly be listening.




You October 27th 06 07:07 PM

ans calculations/ fuel cell battery buffer or cap?
 
In article ,
"Dave" wrote:

i bet you also find that storing explosive gasses in an apartment are also
against code. and laywers would probably consider a fuel cell a generator
also.


Well not really, as a lot of apartments have Explosive GAS piped right
into them..... Never heard of Natural Gas, or even Propane, I guess....
Both are Extremely Explosive, when mixed with air in the correct
ratio.... Duh.....

Dave October 27th 06 07:34 PM

ans calculations/ fuel cell battery buffer or cap?
 
Check a lease on an apartment, or the condo codes, storing propane on or in your
residence or even on your deck is a violation.

You wrote:

In article ,
"Dave" wrote:


i bet you also find that storing explosive gasses in an apartment are also
against code. and laywers would probably consider a fuel cell a generator
also.



Well not really, as a lot of apartments have Explosive GAS piped right
into them..... Never heard of Natural Gas, or even Propane, I guess....
Both are Extremely Explosive, when mixed with air in the correct
ratio.... Duh.....



Richard Clark October 27th 06 07:44 PM

ans calculations/ fuel cell battery buffer or cap?
 
On Fri, 27 Oct 2006 01:59:24 GMT, ml wrote:

it usually starts simple, i wanted somthing better than battery power


Hi Myles,

You are suffering from easy access to an answer to the wrong question.

First, investigate/research DC-DC converters. We've been through this
once before, haven't we?

The various storage methods you've been cycling through
Cell/Battery/Cap all have different voltage parameters compared to the
eventual load. True, the battery naturally fits that 13.6V
requirement, but it eventually fades.

With the right DC-DC converter, you can accommodate almost any
scenario you've described and efficiently transform to a steady
reliable voltage source capable of meeting the current load.

With the right DC-DC converter, you can also meet the requirements for
recharging a cap or a battery from any other source
(Cell/Battery/Cap). Flexibility allows you to move from any power
source to another and still supply your load reliably.

73's
Richard Clark, KB7QHC

K7ITM October 27th 06 08:52 PM

preop/ ans calculations/ fuel cell battery buffer or cap?
 

ml wrote:
In article ,
Tom Ring wrote:

ml wrote:
omitted) it's quite meets
code, very small, very light dosn't pollute or stink

seemed rather sexy the jado can also be powered from small cartridges
making the unit selfcontained and very portable, however this isn't a
requirement of mine but cool benni

the only con for me, seems to be a)not totally going to give me 100w
at full load b) i wish the unit was more than a puny 100w the larger
units i would have to pay full list for and are therefore outta reach


so solath and experiment


Ok, I have applied a simple power budget to what you stated your
original desire was, as opposed to your cut down 2m 5W system.

Using a rig I own, an FT-897, on HF.

Assume 90% receive at 1 amp.
Assume 10% transmit at 15 amps with 100 watts output, (measured as
opposed to the 22 amps claimed in the docs)

This gives 2.4 amps average consumption. (Check my math, the doctor did
a lot during my pre-op today)

1 week is 168 hours which gives us 403 ampere hours.

100AH deep cycle batteries are around 100 each (or less), So that's
about $400 for all the batteries you need for a week without sleep.

A modern top of the line charger, such as produced by Schumacher, is
less than $100, does automatic desulfation, will charge at 50 amps or
greater, and weighs about 6 pounds.

So now we are at under 500 dollars for an emergency power for any ham
that needs to run an HF rig for a whole week.

I just don't see why you want to use the fuel cell, it makes no sense.

tom
K0TAR

tom, am i to understand you had some surgery today? if so, i hope all is
well with you and taking the time to write is appreciated

i am guessing roy's calculation of the total ampre hrs needed is closer
to being correct, but it's 5am and i kinda don't know how to calculate
that so i dunno as stated in my earlier post i don't have the formulas
so i can't act to confirm but i nod my head and presume it's all correct
based on roys math

you are correct about what the rig is doing mine is exactly simular i
would calculate based on 20amps

re your last comments on why i would want a fuel cell, it should be very
clear in all my many posts

5480 watt-hours of battery is more $$ and large than i have practical
room for

i can get the fuel cell for practically nothing and i just thought it
might be able to offer some useful power to top off a battery to
provide some b/u power why not? and also be a fun experiment it runs
quiet , clean and i can get all the fuel i want free always, i would
never be able to get fossel fuels in a blackout or other emerg

so now i inch a drop closer knowing how many what hours my original
abandoned goal would draw , however my current stated goal is to just
power my 5w tx output(draws4amps) 2m mobile rig

and try to calculate how much the battery would be drained in a 1min
tx and then see if the 12v 7amps comming out of the jado would recharge
it fast enough i believe that is what must be calculated for just not
sure how do it, unless you still say a 7amp battery is still 'ok'

my goal was to be able to calculate

so a 7amp battery(or what ever is needed optically this seems like a too
low a #)) w/a 1min 4amp load would be ??%drained
then based on manuf spec's for the battery we could calculate how much
power &time would be needed to top it back off

then it would be simple enough to see if the output of the jado is
sufficient i think thats all thats needed i think that's simple
but i dunno how to calculate it
thanks all i really wanted to do


If your rig draws 4 amps (I assume that's on transmit; it would be an
awful lot of power for a modern receiver), and the fuel cell can put
out 7 amps continuously albeit at slightly reduced voltage, and I
assume it can put out 4 amps at less of a reduction, why are you
worried about it? Unless you are VERY long-winded with your
transmissions, a small 7amp-hour sealed lead acid battery would give
you a couple hours operating time even if it wasn't being continuously
recharged. I'd actually opt instead for some voltage stabilization at
the fuel cell output: a buck-boost regulator would do it. If you
trust the fuel cell to do its job, then trust it. If you don't, then
provide a backup. So what I read between the lines you've written is
that you're going to get this fuel cell, but you don't really trust it.
You don't even trust it to come close to what are apparently its
published ratings.

Pretty much all the formulas you need to figure all this stuff out:
power = voltage times current (watts = volts * amps)
energy = power times time (joules = watts * seconds)
-- total energy needed = sum of (each current times the length
of time that current is drawn)
amp-hours = amps * hours = amps * seconds / 3600sec/hr
battery energy storage in watt-hours = amp-hour rating * volts
(assuming full charge)
battery energy storage in joules = amp-hour rating * volts * 3600
sec/hour
capacitor energy storage = (initial charge voltage)^2 * capacitance / 2
joules = watt-seconds = volts^2 * farads / 2
watt-hours = joules/3600 = volts^2 * farads / 7200

Where is it that you can get a license without knowing at least this
much? Why so much trouble with the concepts of power and energy
calculated from current, voltage and time? (Why is this posted to an
antennas newsgroup?)

Cheers,
Tom


K7ITM October 27th 06 09:18 PM

preop/ ans calculations/ fuel cell battery buffer or cap?
 

ml wrote:
In article ,
Tom Ring wrote:

ml wrote:
omitted) it's quite meets
code, very small, very light dosn't pollute or stink

seemed rather sexy the jado can also be powered from small cartridges
making the unit selfcontained and very portable, however this isn't a
requirement of mine but cool benni

the only con for me, seems to be a)not totally going to give me 100w
at full load b) i wish the unit was more than a puny 100w the larger
units i would have to pay full list for and are therefore outta reach


so solath and experiment


Ok, I have applied a simple power budget to what you stated your
original desire was, as opposed to your cut down 2m 5W system.

Using a rig I own, an FT-897, on HF.

Assume 90% receive at 1 amp.
Assume 10% transmit at 15 amps with 100 watts output, (measured as
opposed to the 22 amps claimed in the docs)

This gives 2.4 amps average consumption. (Check my math, the doctor did
a lot during my pre-op today)

1 week is 168 hours which gives us 403 ampere hours.

100AH deep cycle batteries are around 100 each (or less), So that's
about $400 for all the batteries you need for a week without sleep.

A modern top of the line charger, such as produced by Schumacher, is
less than $100, does automatic desulfation, will charge at 50 amps or
greater, and weighs about 6 pounds.

So now we are at under 500 dollars for an emergency power for any ham
that needs to run an HF rig for a whole week.

I just don't see why you want to use the fuel cell, it makes no sense.

tom
K0TAR

tom, am i to understand you had some surgery today? if so, i hope all is
well with you and taking the time to write is appreciated

i am guessing roy's calculation of the total ampre hrs needed is closer
to being correct, but it's 5am and i kinda don't know how to calculate
that so i dunno as stated in my earlier post i don't have the formulas
so i can't act to confirm but i nod my head and presume it's all correct
based on roys math

you are correct about what the rig is doing mine is exactly simular i
would calculate based on 20amps

re your last comments on why i would want a fuel cell, it should be very
clear in all my many posts

5480 watt-hours of battery is more $$ and large than i have practical
room for

i can get the fuel cell for practically nothing and i just thought it
might be able to offer some useful power to top off a battery to
provide some b/u power why not? and also be a fun experiment it runs
quiet , clean and i can get all the fuel i want free always, i would
never be able to get fossel fuels in a blackout or other emerg

so now i inch a drop closer knowing how many what hours my original
abandoned goal would draw , however my current stated goal is to just
power my 5w tx output(draws4amps) 2m mobile rig

and try to calculate how much the battery would be drained in a 1min
tx and then see if the 12v 7amps comming out of the jado would recharge
it fast enough i believe that is what must be calculated for just not
sure how do it, unless you still say a 7amp battery is still 'ok'

my goal was to be able to calculate

so a 7amp battery(or what ever is needed optically this seems like a too
low a #)) w/a 1min 4amp load would be ??%drained
then based on manuf spec's for the battery we could calculate how much
power &time would be needed to top it back off

then it would be simple enough to see if the output of the jado is
sufficient i think thats all thats needed i think that's simple
but i dunno how to calculate it
thanks all i really wanted to do


If your rig draws 4 amps (I assume that's on transmit; it would be an
awful lot of power for a modern receiver), and the fuel cell can put
out 7 amps continuously albeit at slightly reduced voltage, and I
assume it can put out 4 amps at less of a reduction, why are you
worried about it? Unless you are VERY long-winded with your
transmissions, a small 7amp-hour sealed lead acid battery would give
you a couple hours operating time even if it wasn't being continuously
recharged. I'd actually opt instead for some voltage stabilization at
the fuel cell output: a buck-boost regulator would do it. If you
trust the fuel cell to do its job, then trust it. If you don't, then
provide a backup. So what I read between the lines you've written is
that you're going to get this fuel cell, but you don't really trust it.
You don't even trust it to come close to what are apparently its
published ratings.

Pretty much all the formulas you need to figure all this stuff out:
power = voltage times current (watts = volts * amps)
energy = power times time (joules = watts * seconds)
-- total energy needed = sum of (each current times the length
of time that current is drawn)
amp-hours = amps * hours = amps * seconds / 3600sec/hr
battery energy storage in watt-hours = amp-hour rating * volts
(assuming full charge)
battery energy storage in joules = amp-hour rating * volts * 3600
sec/hour
capacitor energy storage = (initial charge voltage)^2 * capacitance / 2
joules = watt-seconds = volts^2 * farads / 2
watt-hours = joules/3600 = volts^2 * farads / 7200

Where is it that you can get a license without knowing at least this
much? Why so much trouble with the concepts of power and energy
calculated from current, voltage and time? (Why is this posted to an
antennas newsgroup?)

Cheers,
Tom


Jim Kelley October 27th 06 11:07 PM

preop/ ans calculations/ fuel cell battery buffer or cap?
 
K7ITM wrote:

-- total energy needed = sum of (each current times the length
of time that current is drawn)


You probably meant to say current times time is total charge.

73 de AC6XG


Slow Code October 28th 06 01:30 AM

ans calculations/ fuel cell battery buffer or cap?
 
Roy Lewallen wrote in
:

Tom Ring wrote:
. . .
1 week is 168 hours which gives us 403 ampere hours.
. . .


which at 13.6 volts is about 5480 watt-hours. This is the energy storage
requirement.

The OP asked about using a capacitor. The energy stored in a capacitor
is C * V^2 / 2. For capacitance in farads and voltage in volts, the
result is joules, or watt-seconds -- you need 5480 * 3600 ~ 20,000,000
joules in round numbers. So suppose you wanted to store this same amount
of energy in a capacitor, and you had a switching regulator which would
handle 50 volts maximum input voltage. Solving for C, assuming it's
charged to 50 volts,

C = 20,000,000 * 2 / (50^2) = 16,000 farads.

This assumes you can get all the energy out of the capacitor, which
requires your regulator to work down to zero volts. But you'll get 3/4
of the energy out of it if your regulator cuts off at 25 volts, 7/8 if
it cuts off at 12.5 volts, etc.

How does that sound?

Roy Lewallen, W7EL



Send that to me in CW and I'll have a look at it.

SC

K7ITM October 28th 06 02:01 AM

preop/ ans calculations/ fuel cell battery buffer or cap?
 

Jim Kelley wrote:
K7ITM wrote:

-- total energy needed = sum of (each current times the length
of time that current is drawn)


You probably meant to say current times time is total charge.

73 de AC6XG


Yeah, probably something like that. ;-) Actually, what I meant to
write was more like:
-- total energy needed = voltage * sum of (each current times the
length
of time that current is drawn.

Lesseee...unit analysis...volts * amps * time. OK, that looks better.

Thanks, Jim.

Cheers,
Tom


Tom Ring October 28th 06 03:35 AM

ans calculations/ fuel cell battery buffer or cap?
 
You wrote:

Well not really, as a lot of apartments have Explosive GAS piped right
into them..... Never heard of Natural Gas, or even Propane, I guess....
Both are Extremely Explosive, when mixed with air in the correct
ratio.... Duh.....


You will find that from a legal perspective that natural gas piped in is
not at all the same as storing a tank of hydrogen. Natural gas and
propane are very highly regulated as to installation, equipment
attached, etc. Very different than your tank of H2 will be.

tom
K0TAR

Tony VE6MVP October 28th 06 05:01 PM

fuel cell battery buffer or cap?
 
On Thu, 26 Oct 2006 08:53:31 -0700, Jim Kelley
wrote:

Fuel Cell??? That is a pretty pricey option.

More than likely it is 100WH (Watt-hour, not Watt) rated.


https://jadoopower.com/fuel_cell.html


Very interesting.

But

Seems like those fuel canisters are just a bit on the pricey side.
And what fuel do they indeed use? Complete lack of info on that.

I see the website mentions refill stations. What kind of power do
those use? How do they work.

Tony

Tony VE6MVP October 28th 06 05:46 PM

fuel cell battery buffer or cap?
 
On Sat, 28 Oct 2006 16:01:03 GMT, Tony VE6MVP
wrote:

Seems like those fuel canisters are just a bit on the pricey side.


When I run the numbers through I get N-Gen at $1000 and Honda EU1000i
at $790. Close enough for now.

But the fuel is much different. - N-Stor130 is 130 W-h for a cost of
$450. But the Honda fuel consumption is 3.8 hours at rated
continuous duty of 900 watts. Or a 0.6 US gal tank of gas produces
3420 W-h. That's about $2.

So 130 W-h for $450 or 3420 W-h for $2.

Unless you really, really need that absolute quiet of the fuel cell or
have unusual conditions such as the space shuttle then it's a no
brainer to me.

Tony


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