LowPowerLab Forum

Hardware support => Projects => Topic started by: kni on August 11, 2019, 01:03:51 PM

Title: Solar Powered Pump Controller
Post by: kni on August 11, 2019, 01:03:51 PM
This particular project uses a Moteino to activate a submersible pump, which pumps water out of my lake to a couple rows of Strawberries.
It runs off solar power and stores excess energy in a common 12v, 7ah battery.

I posted the project in a blog this time!
https://moteino.blogspot.com/p/solar-pump-controller.html
Title: Re: Solar Powered Pump Controller
Post by: TomWS on August 11, 2019, 08:25:07 PM
Cool project.   I like it!  I did not read all (or much) of your website, so forgive the question:  How many square feet of strawberry patch can you irrigate with a 12V 1A pump?

I'll read the site in detail if the info is there, but this seems like one of those 'great idea, but doesn't scale' kinds of questions (and I'm not dissing, I'm seriously interested).

Thanks for the posting,

Tom
Title: Re: Solar Powered Pump Controller
Post by: kni on August 12, 2019, 08:55:01 AM
Yeah, that's a very good question. Sizing the pump was something I struggled with. It was not as simple as finding a pump with sufficient lift. I went through a few attempts before I found a pump that was suitable. Fortunately, the pumps were all less than $10 each, so the only significant thing I lost was time.

I do not have good quantitative data that would let someone scale the system up significantly, with reasonable assurance it would work. Here is what I know.

Currently there are two 12 foot beds, with 6 plants, each with their own dripper. I used 1/2" water line as the main backbone, then tapped 1/4" line off that to each plant. Since the water is not filtered, I used a small valve, rather than a traditional dripper like this:
https://www.dripdepot.com/item/barb-tubing-coupling-valve-barb-size-quarter-inch-18-inch-color-black

I will say that the pressure I currently have is quite high. Each dripper would shoot a stream of water clear out of the garden if I did not dial each back. In my opinion, one could double size of the garden and still have plenty of pressure.

The charge controller is rated at 5A max discharge, so there is decent room to scale up to a bigger pump. Naturally, one would need a bigger solar panel and possibly a bigger battery.

I am still drinking my Monday morning coffee so my apologies if this rambles.


Title: Re: Solar Powered Pump Controller
Post by: sparky on August 12, 2019, 10:00:09 AM
Great blog,  thanks for taking the time to share all the information!