Opinions on solar water pumping?

[camelback75]

Hi Folks,
We are off grid in SW Colorado.
I want to pump water out of our pond using separate stand alone PV modules NOT connected to our system. What benefit if any, would there be to using a charge controller if I plan to pump directly from the panels, using no batteries? Anyone have experience with solar pumps?

Thanks, Lon 

[zoneblue]

Theres a guy on the NAWs forum who is an expert in this area. You normally use a VFD driven motor, this setup drives the pump only as fast as there is sun. A normal pump has high starting surges which can not be supplied via solar alone typically. But you could try using capacitors to supply the start surge maybe? But you still stuck matching the array to the motor.

[tecnodave]

SHURflo makes low voltage DC pumps much like a motorhome pump that are 36 volts.....perfect match for 72 cell panels.......many folks here in dusty dry California use such a system for a low cost water pumping system.    No cc,no batteries....... only panels connected directly to pump


td

[MGP]

Check out www.lorentz.de they have a range of solar direct pump, resellers world wide,
Very good product 3ph brushless motors, external electronics .

MGP

[vtmaps]

I want to pump water out of our pond using separate stand alone PV modules NOT connected to our system. What benefit if any, would there be to using a charge controller if I plan to pump directly from the panels, using no batteries?

Do a little research on Linear Current Boosters... that would be a better than a charge controller.  Charge controllers are designed to interface with and charge batteries.  Most charge controllers will not even turn on without a battery.

--vtMaps

[cpm]

Just for fun, take a look at http://www.builditsolar.com
Specifically, http://www.builditsolar.com/Projects/SpaceHeating/Components.htm
Down in the pump section.
There are a number of different pumps listed, which might give you some clue of
what options there are available to the DIY mindset types who want to move
water from here to there with the sun.