BoatBanter.com - View Single Post - VW Trickle Charge Solar Panel ... question

Ian Malcolm

wrote:
On Sat, 12 Jan 2008 20:25:15 GMT, (Richard Casady)
wrote:

On Sat, 12 Jan 2008 14:42:49 -0500, wrote:

All they do is try and keep a battery from going totally dead and possibly
freezing while in transit or storage. With a good light source, I'll bet it
would power a small LCD calculator, as long as it wasn't one that prints.

My calculator, a HP48, has 49 keys and a four line display. They don't
make them any larger. I call it the "Calculator that Takes No
Prisoners". Three AAA batteries last over a year. In other words, even
the largest LCD calculators use only tiny ammounts of energy.

Casady

That's exactly why I used one as an example of the very tiny output of those
disposable VW solar panels. Using one to try and keep a marine deep cycle
battery fully topped up is futile.

Nominal 3.4 watt panel IIC so its good for about 1/4 A peak output.
Allowing for cloud cover, panel orientation etc. you'd be very lucky to
see more than 1/4 AH per day. Does anyone know if they are weather
resistant? If you are on a mooring, at least a couple of them will keep
up with the self discharge. A Rule 750 bilge pump pulls a nominal 2.8 A
so it *might* keep up with a few minutes a day of pump activation. You
can forget about running fans, Navtex or anything else trhats on all the
time.

--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
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