Douglas Archbald's posts

The reason I was specifying that size pump is that's what I've always used at this cabin (and I have an extra one of that capacity), but now I'm building an elevated holding tank at a different location on the property and this holding tank will just serve a sleeping cabin with limited water needs.  The sleeping cabin is about  70 feet from the water level and will be about 20 feet above the water level.  I don't want to have a float switch involved because that will require an electrical line from the holding tank to the pump (i.e., 70+ feet).  The pump has to be very close to the water level because that's how these style of pumps operate best.  They can't "pull" water  very high, but can "push" water a long ways and up quite high (my current pump that supplies water to the cabin is about 1 foot from the water; the cabin is about 60 feet from the water and about 20 feet above the water level).  So for the pump serving the new holding tank, I just want a small panel wired directly to the pump.  Don't want a battery involved because batteries require maintenance.

MY PLANNED APPLICATION:  I want to power a SHURFLOW 12V, 3 GPM, DIAPHRAGM WATER PUMP  [#2088-343-435] directly from a PV panel (don't want to have battery involved).  The pump will fill a 20 gal holding tank; tank only needs refill about once/week.    I would only run the pump during afternoon sun.

QUESTIONS:  What's the smallest size panel I can get away with for this use?  Would I need a charge controller?  The pump's max voltage allowed is 13.6.  The pump is 7 amps.

Thanks for your reply.