Supplemental solar pool pump and filter??

[bensmail]

I want to do a solar project for long term power outages but I would also like it to be some use year round. The perfect place is for pool filtration because I can directly run a pump from the solar panels without the need to store a lot of power in batteries, large inverters, etc.. I JUST got a new variable speed pool pump and going 100% solar is expensive so I do not want to go there.

What I would LIKE to do is build a small waterfall / fountain at the shallow end of the pool, run a DC pool pump 12v or 24v that just operates the waterfall when the sun is out, with a small basic cartridge filter. This would give some filtration in long term power outages and also allow me to run the main pump less.

Looking for DC pumps is difficult because there are just so many out there and none that I find are good choices for this project. They are either too small rinky-dink 1gph $15 pumps or $400 to $1000 pumps. I would like something in the $100-$200 range. This will not be used to clean the pool, I can use the main pump when I need more power. I assume I need some sort of self priming pump since I do not want a submersible in the pool all the time.

Any suggestions on where and what to look for? Has anyone else done anything like this?

In-ground ~20,000 gallon.

 

[mas985]

You can maintain a pool indefinitely without a pump. Chlorine is what keeps algae at bay, not running the pump. The pump just helps distribute CL but that can also be done by hand.

Seems like a lot of effort for very little benefit.

 

[bensmail]

?? I guess that's why every pool has a filter pump? The benefit is enhancing my pool with a waterfall, reduce the use and cost of running the 240v pump that I do not plan to discontinue AND have a solar setup that can help out in extended power outages by running some LED lighting, 12v car fans, phone charging, etc...

 

[mas985]

My point was that you don't really need a back up when power goes out. You can maintain a pool without pump for an extended period of time. The pump just makes maintenance easier.

With a VS pump, you already have an efficient system so I don't see adding a very small pump is going to help make it any more efficient. In order to do that, you need a substantial solar pump that can move and circulate the water via the main plumbing.

Something like this: SunRay Solar Pool Pumps - Solar Powered Pool Pumps - Residential Commercial Solar Energy Solutions - SunRay Engineering

But they are not cheap and the lifetime cost will certainly be higher than if you did nothing.

 

[bensmail]

you already have an efficient system so I don't see adding a very small pump is going to help make it any more efficient.

More efficiency is not my goal. As I stated already, I want to make a solar project and I want it to be useful year round and not just when the power goes down for extended periods. I have wanted a pool waterfall and with the right DC pump I should be able to make this work on solar. Depending on the pump, I may be able to add a small second filter or even a solar heating panel. Other than that I plan on charging a marine battery for powering a small inverter, LED lighting, etc..

I am looking for pump recommendations, not opinions on how useless this project is.

 

[mas985]

I don't think I ever said it was a useless project.

There have been many posts over the years attempting to do exactly what you are trying to do (just the pump part) and the outcome is always the same. To do what you want to do is very expensive and generally not worth the cost. The requirements you gave above, specifically a self priming non submersible pump, is going to require a centrifugal self priming DC pump and it is nearly impossible find those in very small sizes and the cost of the pump alone is usually well over $400. Because of the size (i.e. power requirements) of pump, you will need a fairly large PV panel to run it. So the costs are going to mirror that of the SunRay system I posted above.

If you went with a lower powered system, similar to a pond pump, the flow rate is very low and would not be sufficient for either a waterfall or thermal solar panels.

The higher the flow rate, the higher the power is required to produce it. The problem here is you have conflicting requirements. You want it cheap but you also want something that is powerful. Those two things are mutually exclusive so you will have to compromise on something.

 

[CJadamec]

I'm just going to mirror what Mark has said the SunRay pump he linked to is actually a nice looking piece of kit. Reasonably priced for what it does as well. I looked for a while yesterday to get a pump capable of doing what you are looking for is 400+ just for the pump and almost all of what I found was only rated for intermittent duty. You need something rated for continuous use for what you are looking for. DC powered motors are expensive there's really not any way to get around that cost because of the price of the copper it takes to make them.

 

[Paulk]

being a new member here today, take my input with a grain of salt. But I do have a fair amount of experience with solar power. I have a solar panels on my house in Berkeley, but I also am totally off the grid on my ranch. I have a complete woodshop powered off the grid. As others have said, that is expensive. But most of us off the grid folks often have water pumping needs. We pump water during the sun hours and don't when it is not sunny. If you live with pumping that way only, then there are plenty of small dc pumps around that would probably do ok for you. Sun Ray seems to be a decent pump, from their website at least. Some of the pumps look a bit like some of the Sun Pumps line. Quite possibly made by Sun Pump. Most of those pumps are made to be used for pools or other uses beyond just a small water fall. I suspect, but haven't looked far into it, that you could go for something cheaper, maybe Shurflo or someone has something that would do enough? I'm pretty sure you could find one that would handle 5 gal per minute easily with that low a head. Again, you would need to realize you probably need a couple of panels, and perhaps a controller, and then the pump.
Another route would be trusting luck and going for one of the DC brushless, variable speed, (all SOUNDS good huh?) pumps made in China. Buy off Alibaba or such and you could get one for a few hundred. I see some of the pretty big names in pool supplies offering systems for ~$900 or more, where they are offered on Alibaba for 1/3rd that.
I'm trying to decide myself on what DC pump to buy. Being off the grid where I'm putting in an AGP, I definitely will only be pumping during the sunlight hours. Yes, I have batteries that I have on my main system, but I'm sure not going to do that. So I'm studying all the potential manufacturers. I have a Lorentz pump now, and have had one for decades. They are very good, but also very expensive. DC pumps are getting a lot more affordable.
paul