"Skip Gundlach" skipgundlach sez use my name at earthlink dot fishcatcher
(net) - with apologies for the spamtrap wrote in message
...
Hi, Y'all...

Well...

"Larry W4CSC" wrote in message
...

snipped bit was here
Hmm...5A from a big solar panel or 15A from a wind generator =
5X12hrs=60AH
per day if the sun shines or 360AH wind power in a full gale 24/7.

Not much of a real powerhouse, is it, huge batteries or small
batteries...

Plan on using the big alternator on the engine every day in this
configuration.

Hm. Help me with the math. As a lapsed math, physics and chem major, I
don't remember my stuff all that well. However, I'll have right in the
neighborhood of 500W solar, and a KISS wind generator in the Caribbean.
Various vendors suggest I take the wattage and divide by 3, or 4 if really
lousy weather, for a reasonable typical AH input, daily. My math has that
at 170-125AH/day, plus some other unknown - but apparently pretty
substantial - AH from a KISS.

Our anticipated daily budget is about 125AH; we'll have (for simplicity in
this calculation) ~1250AH capacity. It's our presumption that we'll have
4-5 days capacity, in the most unimaginable (in the Caribbean)
circumstance
of continuous no wind or sun.

Have I missed something here?

Hi Skip, I'm looking at your math and trying to work out how you came up
with 170-125AH/day generated by your solar panels.

Will this 500 watt panel array ever actually put out 500watts? Or, as you
said above, will it really be only a quarter to a third of this ? If so,
how many hours a day will this panel put out this kind of wattage? Perhaps
a couple of hours on either side of noon with diminished output before and
after this time?

500 watt panel /14.5 volt supply = 35 amps of current.
A third of this is only about 12 amps or so. For about 4 hours is 4 hours x
12 amps = 48 AH per day. Perhaps you will get some useful power out of the
rest of the available daylight, perhaps another 22 AH or so, that still only
gives you 60 AH per day or so, no? Which doesn't seem to come close to
filling your anticipated daily power budget, let alone leave anything to
replenish the batteries from the drawdown on cloudy days.

Perhaps I've missed somthing here?

More snipped bits

Thanks.

L8R

Skip (about to head back to the boat for another couple weeks, this time,
this part, of the refit)


--
Morgan 461 #2
SV Flying Pig
http://tinyurl.com/384p2

"There is nothing-absolutely nothing-half so much worth doing as simply
messing about in boats.
In or out of 'em, it doesn't matter. Nothing seems really to matter,
that's
the charm of it.
Whether you get away, or whether you don't; whether you arrive at your
destination or whether you reach somewhere else, or whether you never get
anywhere at all, you're always busy, and you never do anything in
particular; and when you've done it there's always something else to do,
and
you can do it if you like, but you'd much better not."


--
Ken Heaton & Anne Tobin
Cape Breton Island, Canada
kenheaton AT ess wye dee DOT eastlink DOT ca