Posted by wmbjkREMOVE on July 18, 2008, 12:20 am
The OP only mentioned power. Ghinius ghio recommended the use of a
solar pump, implying that he knows something about the subject. So I
asked him to be specific, and specified a modest need of 8gpm and 80'
of head. I don't believe he's ever installed anything more complicated
than an RV-type 12V Shurflow, and I predict that if he tries to
pretend any knowledge, he'll bungle most everything he writes, as
usual. 'Course, that's a bit like predicting that water is wet. :-)
Posted by Ron Rosenfeld on July 18, 2008, 12:00 am
On Thu, 17 Jul 2008 13:26:36 -0700, wmbjkREMOVE@citlink.net wrote:
Some years ago I spec'd a solar water-pumping system for a neighbor.
Grundfos has some pretty neat tools to do this with. Dick has some
cottages that he rents out during the summer, and has a water requirement
then of about 1100 gallons per day. His current method is to run a
generator to pump water up hill to some storage tanks, and then the water
is distributed from there. So he already has the storage tanks.
I don't recall the costs (and they would be different now, anyway), but,
assuming he used the recommended Grundfos pump, he could have replaced his
generator with a PV array rated at 0.325 kWp (5 65W panels).
Posted by wmbjkREMOVE on July 18, 2008, 12:45 am
On Thu, 17 Jul 2008 20:00:17 -0400, Ron Rosenfeld
Yes, quite a bit less than 154 50W panels, eh? :-) I've installed
several Grundfos SQFs, mostly for remote cattle-watering. Impressive
performance and lots of neat features. About $400 these days for the
pump and another $50 for the float-capable controller if needed. One
that's installed nearby with an over-sized fixed array produces 10gpm
pretty much whenever there's sun. Its installation did away with the
need for a loooong drive to the site every few days to gas up a
BTW, the OP's need was probably only a few times less than your
friend's. So you skated dangerously close to giving ghio the answer to
the 8gpm 80'head question. :-)
Posted by Ron Rosenfeld on July 18, 2008, 2:14 am
On Thu, 17 Jul 2008 17:45:41 -0700, wmbjkREMOVE@citlink.net wrote:
I guess that would equate to about 7 50W panels or 9 of the "Ghio Test
Condition" panels (that's the 14V 2.94A at NOCT specification with 17V at
no load). Let me see ... yes! that is less than 154 panels!
Maybe he'll go for it one of these days.
That's only a slight increase in price from when I spec'd it. I think they
were about $100-$200 then.
My bad :-(
Posted by bealiba on July 17, 2008, 11:47 pm
So you now agree with me. Ditch the pump.
Interesting statement. What do you base it on? What pump and panel
combination would you suggest?
As I said;
The truth is that neither you or Tweedledum have been able to prove
the formula wrong. You say it's wrong but can't show how it's wrong.
Neither of you have come up with a calculated system to do the job.
You are both, in fact, all talk and no walk.