Solar powered 12v water pump advise

    I bought a small [11W] solar panel and a 12v water pump a few years
ago for a small fountain. Works fine in full sun, but the panel is
rather adamant on the amount of shade or overcast that it will accept
before it will power the pump.

   I would like to get a bigger array and use a battery to store the
extra energy. Common sense is not the overriding concern here. The HF
45W array seems to be quite adequate, but my question concerns the
converter and battery charger [and the type of battery as well!].

   Will someone care to guide the solar powered challenged individual
through the process?

 

  I would say a battery, charge controller and something to turn the
pump on and off. If you want the pump to come on when there is
enough sun, it would have to be a separate circuit now that you have
a battery. Just a power device that is enabled once the voltage and
current from the charge controller is adequate should do it. Or you
could put it on a timer that takes very little power to run.

 Battery type? Lead acid?

SJC wrote:

 

Depends on what kind of capacity you need, the load and maintanance you
are willing to do. It sounds like the pump takes maybe 6 watts, or so.
Do you want the pump to run even when there is no sun? For how long?
There are a few variables missing.
  Lead acid could be the kind you have to add water to or the kind you =
don't.
I use an AGM sealed deep cycle from Johnson Controls, but most of theirs
are automobile size. If you only need 6 watt hours of storage you could =
use
NiMH D cells. Those are available at Radio Shack along with the battery =
holders.
It is up to you.

 I'd like constant operation if possible. If not, then shut off on
sundown, my concern is the overheating of the water in a 75 gal stock
tank in direct sun.

SJC wrote:

holders.