Bulding a solar water well pump

It was just an experiment. I have 3 x 55 gallon drums linked together. It takes a long time for it to irrigate, and I was only adjusting the valve manually. Given the insane evaporation we have here in Florida, it wasn't a complete solution. However, I could turn it on midday for 20 minutes and it gave enough water to keep my garden plants from wilting in the extreme summer sun. I had a very crazy setup experimenting with different irrigation devices and flood mitigation since we have been known to get 10"+ in a day when tropical storms hit.

I was using some hose with emitters built in. I'm sure if I had some sort of controller on it that I could have made it work better. Having to rely on memory and occasionally having the barrels empty by forgetting it made it a hassle. But it was a start.

I also messed around with overhead sprinklers which I was getting a ~8' radius vs the 12' radius it would get at 30 PSI. Doubling pressure doesn't double output because the restriction of the emitting device becomes more of an inhibitor to flow at higher pressures. That's why I mentioned the fuel injector calculator because it is easy to punch in the given rating of flow for a given pressure and figure out the new flow at a different pressure. I think a combination of overhead watering early in the day before the sun is strong and complemented with drip irrigation will work great for what I am trying to do. Not having to use pumps will make the system that much more reliable for me.

Now that I have property with ~30 feet of slope, I'm hoping to build rainwater collection at the top of the hill. That should give me significant enough pressure for my needs. One thing I learned watching some hydroponic/aquaponic videos is to have a separate reservoir for batch irrigation. Changes in water level will affect the pressure (and flow) so timers are going to give variable output. If you make a tank that holds the gallons you need, with an overflow to drain back into the system or a float switch, you can have a valve control filling the holding tank. As long as it stays open long enough to fill it even when the main tank is low then you can get consistent output from the gravity fed irrigation.

I bring this up because using solar can be variable. By having a few days worth of storage, you could 'work while the sun is shining' and fill a tank when there is plenty of sun, and still have a usable amount of water even through an extended period of cloudy days. Of course you may not need as much water when there isn't a lot of sun, and panels usually provide some power even on cloudy days, but you can design a more resilient system by adding storage.

If you got some wind there, on a regular basis, you could get an old 24 volt 3phase stepper motor from an old printer. hook up an ac/dc converter, and charge up some rechargeable batteries to run the pump. you can get some little 12 volt submersable pumps and whala,,,amazon i think is where my buddy got his. if you need a little more current for your pump just whip up a current booster, providing it reaches the voltage requirements.

somewhat similar gravity setup as yours. I get an inexpensive kit at the Walmart a wile back for that

Yeah, each model has their own rating (nominal). If they're engineered good, sprinklers/emitters are going to behave in the exact opposite way that you wanted them to. Two identical sprinklers will try to keep the range/flow difference to a minimum for a given range of operating pressure... because uniformity. Increasing pressure over nominal increases wear. Above a certain limit you're only going to get finer droplets, not increased range. Some folks use this trick for certain crops that like micro-droplets :smiley:

You also have self-compensating drip emitters for when you're irrigating slopes and your water source is at the bottom (worst case scenario if you want uniformity).

But I agree, using solar energy when it's available, to pump water to a certain height is a good way of accumulating energy (and quantity). That thing with overflow and a float switch for refill sounds neat.

Have any of you tried ollas? I live in Eastern Europe and I don't think many people here have even heard about them, but I hear it's getting more popular in the US. Because it's low pressure (no pressure), water efficient etc. Also, I see that common practice with them is to get them out of the ground before winter to prevent freeze-breaking, which would be a non-issue in Florida, so there's that.

I have tried homemade ollas made from Terra Cotta pots, they work ok but I did not continue using them for more than a season. might be good for drought ridden regions but here I have all the free water I want so more work for me than there worth, also if something with an aggressive root system is near its gonna pretty much encase them fully and take all the water. This is why I would avoid any kind of underground system, trees will find things.

Anyways, I think my best course of action is to try out a few different ideas for the actual pumping, find a solution that will be reasonably effective then start on the power system necessary to run it. No sense in buying a horse that can't pull your cart.

Alright new plan.

This battery should be ok I only need 5-10 gallons tops so I don't need anything too large.

Unsure of what pump to get my considerations are below,

These diaphragm pumps seem like a good option as they seem to be the cheapest capable to doing the job and as a plus have a pressure switch so all control can be handled with valves.
I will be adding an inline filter to hopefully remove any partials large enough to damage the pump

it has a head pressure of 165ft so it should do the job.
The only issue is it dose not specify if it is self priming or not, some people in the reviews say it is and some say no. So with the assumption this dose not self prime how do I deal with that?

This one has a supposed head pressure of 90 meters so that is also plenty and it is self priming but the reviews are pretty lack luster so a dubious option at best .

this one is rated ok who knows


cheapest I found with appropriate ratings

I've never actually seen those pumps used for irrigation before. They are used for fertigation when you need to inject a precise amount of liquid fertilizer over time, into the irrigation water pipeline (which is already under pressure - that's why these pumps are rated for such high pressure).

I guess they might be OK if you're going solar, and pumping to a container placed somewhere high to give you enough pressure for when you irrigate later. And if you automate everything so they can pump whenever there's juice, since their flow rate sucks... Another plus would be that you distribute the effects on the groundwater table over the whole day.

These don't seem like they could handle irrigating for a whole season. But they are extremely cheap for what they offer so there's that.

No idea about the battery, though...

Prime by setting everything up and filling all cavities between the surface of the groundwater and the pump's outlet with water. That means: a completely filled inlet hose and the pump cavities. Outlet hose can be filled too but it's not a requirement.

I think ive decided on the cheapest possiple pump I could find

Like I said I only need a small amount of water so this with a pipe strainer should be ok I think, I do get some sand occasionally. I will run the pump for an hour or less so for the time being I will just charge up the battery with a trickle charger then carry it with me and do solar later on if this works out well.

Should work out ok, we will see $17 is not the end of the world if it dose not work out.

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Did you already find that pipe strainer and for how much money?

I already have one with 1/2 threads just gonna add some fittings too it for like 45 cents or so and it will work fine. they go for about 5 or 6 dollars though.

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I decided to plumb it useing 1/2" pvc, this might be a bad idea considering now the pump has too lift more water but then getts bottle necked when it gets too the smaller barb fittings on the pump. We will see tomorrow when I actually install the long ass pipe i glued together. I maybe should have just used a tube, maybe a screen hose clamped too the end but eh backup plan I guess.

I just had a thought here... perhaps a pump used for building your own water cooler in a pc may work for you?

This is a bit different, it's a video on pond aeration, but you could easily substitute a 12V pump in place of the aerator that has a 15 foot head rating. Anything solar and wind, this guys channel is very educational.

wellp setback, I tested the pump and with the pump mounted high it cannot pump water higher than a little under 9 feet. looking at the ad they claim a suction height of less than 2 feet but a Max Head of Over 150FT so that complicates things a bit. I need too suck so I don't think any of the pumps I was looking at can do it.

I did learn my water table is about 15 ft down though

anybody happen to know of a pump that can do the trick? if not I suppose i'll have to try and construct something I can fit down in there

I'll admit that I didn't read through all this, but I would use a small pump with a panel and battery to regulate it. I would use a pump with enough head pressure and put a barrel on a stand so you always have excess supply regardless of solar power. Low and slow, let gravity do the work after it's set up.

Dammit, now I read more. A couple deep cycle batteries and a triggered pump cycle and the reservoir above could work. Pulling from the top is the issue, you probably have to prime your pump as it is.

So, on a physics basis you could theoretically use the electric power to run a compressor on a cycle timer with a ram-pump style tube with a flapper valve and check valve. I suggest digging a bigger hole...

Just get a submersible pump and run it from a battery for whatever the duty cycle your solar can supply. If it can only run 1 hour a day put it on a 1 hour timer per day.

Would be easier to get a 12V pump but with an inverter you could use a 120V /240V pump.

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Welp, I guess you're gonna have to bore a wider hole and go for a submersible. Unless you somehow either get that thing closer to the water surface or find a pump that can handle 15 ft of height on the inlet and still be within budget and specs.

I went down too the farm store and got me a nice big pump for about $100 with 1/2 inch fittings and it works great it pumped more water than I get out of my garden hose till it stopped pumping.
I must have gotten a leak in the pvc it proubley got cracked during installation. The pump itself is undamaged I tested it. I cannot get the piping to hold any water up at all and it did not pump the well dry. I'm gonna head out and get 25 feet of 1/2 inch tubing a hose clamp and a 1/2 thread to barb fitting adapter and correct that issue unless anybody had a better idea as to what I should stick down there.

note there was a lot of sand down in the bottom of my well I could feel it with the end of my pipe, now there is none as the pump pumped it all out and went right through my pipe strainer so I'm gonna just hope that dose not damage my pump, it hasent so far.

also note under my top soil is just lose water bearing sand the sand layer is high enough you can reach it with a post digger. I would have no trouble driving a 3 inch steel well spike down any reasonable distance by hand with a post hammer

You can alway make a floaty for a submersible pump to keep it off the bottom with some foam and rope aka a fishing lure thing.

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