Solar PV direct Pumping system. What size solar panel do I need?

[ERIC5249]

It appears the pump controller needs higher voltage than a single 12 volt panel puts out. If you add another 100 watt 12 volt panel you need to series wire them.

Alright, well I was planning on using a dc-dc buck converter instead of a pump controller. I was not able to find a pump controller for this specific pump.

[littleharbor]

This project would really be much simpler if you just went with a small sealed 12 volt battery and a small inexpensive controller.

[ERIC5249]

I agree, but my group wants to do this without batteries.

[J.P.M.]

I agree, but my group wants to do this without batteries.

Is your group aware of the technical, maintenance and financial consequences of their perhaps ill-informed desires ? Or are they more of a "I saw this on U-tube so it must be a snap" type of mentality ?

[PNPmacnab]

What is the intended use of this pump? Are you charging a tank or just using this for watering? Have you bought the panel already, buying a battery voltage panel is a big mistake cost and performance wise. If you can operate the pump at a lower voltage like 9-10V, I would do that. Solar is a lot like a puppy or wife, it seems like a good idea at first.

[LETitROLL]

Hello! I am working on a project where I need to pump water from one tank to another one. I am located in Rockford, IL and need to pump this system for a few hours. The pump that I am looking at using is a Shurflo 12 VDC pump (Model # 2088-514-145). I need 10 PSI and 2.90 GPM and the current needed for the pump is 5.6. I am not going to use any batteries as they are expensive, but I am wanting to use a Shurflo pump controller, 902-200 9300 series 12/24 V, to get a better performance from the pump. The one thing I am not sure of is what size solar panel do I need to run this pump? I calculated that I would need a 100 Watt pump, but I am not sure if this is correct.

Batteries are only expensive when you use them to store energy and then use that energy at a later time over and over, It would be much simpler and cheaper in most cases like yours to just use a used car battery to satisfy the circuit and use a Cheap PWM controller, you don't need to store energy, if you are only going to use the system while the sun is up, the battery will just float most of the time, with the bonus of your system still working when a cloud passes by. Most cheap controllers can handle that kind of current on the load outputs and they usually have a timer and LVD to keep things happy, you just have to make sure and use a timer or manually control the system, but you are only going to get a working pump limited time your other way anyhow.

[PCH]

How did you solve this problem? I wish to do the same.

[Mike90250]

How did you solve this problem? I wish to do the same.

Which is the problem you wish to solve? One small difference in YOUR install, will make a difference in the solution.