Solar powered Pool Pump

[JoeHam]

I am looking to help a friend come up with a way to convert his pool pump to solar, it is currently on grid. The pool is around 20,000 gallons and has a 1.5 HP 240 Vac pump with a sand filter.

The location is sunny Tucson Arizona. If the pump only ran when the sun was shining that should be adequate. The goal is to have it completely off grid and self sufficient.

It seems to me that a system with enough solar panels and minimal battery usage would be best. The systems I have built for myself are primarily battery based 24 hour systems so this is a different application than I am used to.

My first thought is a completely battery less or minimal battery use system. The Phocos Any-Grid is one example of this type of solution.

A second thought would be to convert to a DC pool pump which could run directly from solar converted to whatever the necessary DC voltage would be.

Before I start to learn more about either of those possible solutions I wanted to see if anyone has been there/ done that with a solution I am not considering.

Any thoughts ?

Thanks in advance,

Joe

 

[WYtreasure]

How about posting a link to the example you mention?

I look forward to the outcome.

 

[Browneye]

Subscribed out of curiosity, since I have one of those and a 25K gl pool. It runs about 4-5 hours a day, but should run up to 8 hours on long sunny days.

Doing some basic math:
1.5HP pool pump draws 17A at 240V to start, then 12A running.
So 12A running at 240V is 2880 watts. More to start the pump.

I'm curious how a PV array could be configured to power that. Maybe there's a soft-start setup for them.
8 to 10 - 400W panels might provide enough?

 

[Niz76]

Keep in mind that most typical pool pumps have the option to be switched to run on either 220v or 110v. Also interested to hear the simplest way to achieve this. Maybe add larger or more capacitors to aid in startup? Hmm...

 

[HackNFly]

I just bought this pool pump from amazon this week:

Solar Swimming Pool Pump, PWS Powerful Solar Water Pump with MPPT Controller,72VDC, 1.2HP, 62ft, 92GPM,Suitable for Salt Water, JP21-19/900


Unfortunately it's out of stock and all that shows up is the 0.5 HP version. the 1.2 HP version was $787.51 total.

It runs on 72 v and I picked up 4 330w panels with cracked glass at $40 / piece. I ordered 2 check valves as well:

Custom Molded Products CMP 1.5" x 2" HydroSeal Check Valve, 2 Lb Spring, Corrosion Resistant - 25830-350-000 - INYOPools.com

Swimming Pool Check Valve 1 1/2" Inside 2" Outside 2 Lb. Spring

www.inyopools.com

I have a spa attached to my pool, so I want to be able to run the pump at night too, and if we have too many rainy days I'd like a back up, the valves let you do that. From my calculations replacing my inefficient 1 HP pump and filtering all year rather than replacing the saltwater every year, it should pay itself off in 7 years or so.

 

[JoeHam]

Sorry I have been on the road for work.

I don’t have any answers but my current thinking is :

To stay with 240Vac a large enough inverter and some battery to get it started would be necessary. Then a solar array with sufficient power to keep it going should do the trick. Obviously just for daylight hours.

I’ll be asking my friend if replacing the pool pump is an option. I would think DC is the way to go if a change is in order.

I wasn’t aware that a pool pump can switch from 120 or 240. No power savings but it would make some of the 120 all in ones an option.

For many of the budget friendly ones you need two Units to produce 240. Obviously more expense.

Two candidates would be the MPP LV 6548 Will has done videos on and the Phocos stuff like this. https://www.phocos.com/product/psw-h-hybrid-inverter-charger/

Just two examples, neither of which I have any experience with.

Thanks to everyone for the ideas so far.

 

[HackNFly]

My thought process was that it might be more expensive to try and make use of the same pump. Surge loads can be huge. So I'd need a battery as well as the inverter. My pump is also 240v. Although as you mentioned many have the ability to run on 120 as well. Unfortunately I ran into an issue with the PWS pump already, the collar was broken out of the box. I'm trying to contact the manufacturer, they're based out of China but the brand has been around for a decade. I'd say you get what you pay for, but I had this happen with a Hayward sand filter and had to buy the part out of pocket because their support was so bad. I'll update when I get it working.

 

[wattmatters]

I am looking to help a friend come up with a way to convert his pool pump to solar, it is currently on grid. The pool is around 20,000 gallons and has a 1.5 HP 240 Vac pump with a sand filter.

Why such a high powered pump?

Get an efficient variable/multi-speed pump instead.

My old single speed pump used to draw 1200W (1.6hp) but my current pump draws about 900W (1.2hp) on its start up cycle for 5-min then drops into all-day running mode at ~320W (0.43hp).

Now your pool is a little bigger than ours (~13,500 gal) so it might need a slightly higher powered model, but I would definitely be looking at modern variable speed pumps. They are just WAY better. Not only less power/energy required but they are also a LOT quieter.

I run mine from a small off-grid solar PV/battery set up which is mostly for grid outage backup. Have a smart switch integrated with Home Assistant so the pump duty cycle automatically adjusts with the length of day as the seasons change, and also if weather is lousy and I don't want to discharge the battery too much, it will also shut down the pump early.

 

[Nobodybusiness]

I am looking to help a friend come up with a way to convert his pool pump to solar, it is currently on grid. The pool is around 20,000 gallons and has a 1.5 HP 240 Vac pump with a sand filter.

The location is sunny Tucson Arizona. If the pump only ran when the sun was shining that should be adequate. The goal is to have it completely off grid and self sufficient.

It seems to me that a system with enough solar panels and minimal battery usage would be best. The systems I have built for myself are primarily battery based 24 hour systems so this is a different application than I am used to.

My first thought is a completely battery less or minimal battery use system. The Phocos Any-Grid is one example of this type of solution.

A second thought would be to convert to a DC pool pump which could run directly from solar converted to whatever the necessary DC voltage would be.

Before I start to learn more about either of those possible solutions I wanted to see if anyone has been there/ done that with a solution I am not considering.

Any thoughts ?

Thanks in advance,

Joe

I would look at Grundfos or even RPS Solar might have a circulation pump.

 

[tomy2]

I just bought this pool pump from amazon this week:

Solar Swimming Pool Pump, PWS Powerful Solar Water Pump with MPPT Controller,72VDC, 1.2HP, 62ft, 92GPM,Suitable for Salt Water, JP21-19/900


Unfortunately it's out of stock and all that shows up is the 0.5 HP version. the 1.2 HP version was $787.51 total.

It runs on 72 v and I picked up 4 330w panels with cracked glass at $40 / piece. I ordered 2 check valves as well:

Custom Molded Products CMP 1.5" x 2" HydroSeal Check Valve, 2 Lb Spring, Corrosion Resistant - 25830-350-000 - INYOPools.com

Swimming Pool Check Valve 1 1/2" Inside 2" Outside 2 Lb. Spring

www.inyopools.com

I have a spa attached to my pool, so I want to be able to run the pump at night too, and if we have too many rainy days I'd like a back up, the valves let you do that. From my calculations replacing my inefficient 1 HP pump and filtering all year rather than replacing the saltwater every year, it should pay itself off in 7 years or so.

this looks like a good deal, I have been looking at various pumps for months, mostly on ebay. You definetly need to can the old single speed pump, and the new brand name variable speed pumps start at over $1k. amazon has a 3/4 hp version listed today for about $100. less. But if, like me, you want to run it thru a sand filter, the 1.2 HP version would probably be better. of course you have to remember that this is a fairly new Chinese manufacturer, without a proven track record. although the reviews say that there customer service is good so far.
The other option is to buy a cheap chinese variable speed pump that runs on 110volts ($400. to $500.) and not easy to find. then you would need an inverter, charge controller and more panels.
In California electricity is pricey, I figure this would save me about $400/year. So with the panels, it would have to last AT LEAST three YEARS in order to break even. It sounds good, but there is a gamble factor. Also in California single speed AC pool pumps are now banned.

 

[pvdude]

Not sure if this helps, but I set the timers so that the pool pumps run during peak sun time.
They run directly off the solar inverter, and the PV provides the power.
Here is the load with both pool pumps running, the PV is powering the pumps, and when clouds reduce the PV output, the inverter borrows from the grid until the sun comes back.
I put in a double-throw transfer switch to be able to switch the pumps to the grid if needed.

 

[tomy2]

Not sure if this helps, but I set the timers so that the pool pumps run during peak sun time.
They run directly off the solar inverter, and the PV provides the power.
Here is the load with both pool pumps running, the PV is powering the pumps, and when clouds reduce the PV output, the inverter borrows from the grid until the sun comes back.
I put in a double-throw transfer switch to be able to switch the pumps to the grid if needed.
View attachment 91547
View attachment 91548

you say pumps? more than one? what kind, ac or dc?

 

[Hedges]

I think best option is install grid-tie PV with net metering.
Next best is zero-export grid-tie PV.

Another option is bootleg grid-tie: Install a grid-tie inverter behind the switch which turns on pool pump. Feed it an array of PV panels, or two arrays, one SE and one SW orientation. Size this PV system so it will supply most of the pump load, but never more than the pump draws so it won't export.

I have a VFD running 3-phase pool pump. I've contemplated feeding PV to the DC rail of the VFD. Need to ensure it never exceeds rated voltage. Also must never backfeed DC into grid (e.g. due to failed diodes.)
This could operate as PV direct if I configured a PID loop to vary pump speed so DC rail holds constant voltage.

There are PV direct VFD available.

 

[A.Justice]

Like @wattmatters mentioned above, if going solar, for only the pool, I would highly recommend a VFD pump. Pentair makes good ones, IMHO. (The Jandy units have a ridiculous sensitivity to lightning strikes nearby. If you have a strike within a quarter mile of your house, you're pretty much guaranteed to have to swap out your Jandy VFD. In their defense, they always take care of it under warranty though. Everything else Jandy makes is good by me.)

I can't recall off the top of my head which ones, but I know there's a few models of VFD pumps that can take 240v split phase, OR 120v single phase. The pump doesn't have quite as much "oomph" on 120, but generally speaking, they function just fine. The majority of older, single speed pumps have wiring diagrams in the back, and all you need to do is switch a jumper, move a leg, and you should be good to switch over to 120v. I would imagine it would be much cheaper to use a single phase inverter.

Remember you'll have to run the pool even on no-solar days too, so some amount of battery storage is going to be necessary. The variable frequency drive would be very helpful so you could lower the speed (and power consumption) of your pump on days where you don't have solar coming in. I think a DC pump would be a viable option ONLY if you intended on running the pool exclusively from solar, otherwise if you switch back to the grid you would need a large AC to DC converter, or you would need to leave the old AC pump system in place for backup.

IMHO, running a pool off of solar is very similar to running an HVAC cooling system. The inrush is similar (LRA is the biggest obstacle on both systems) and the use times (during the day, mostly) are pretty close.

 

[Texas-Mark]

What I have done is simply use an inverter running off a battery bank, that charges during the day. Buy a better low voltage cutoff than what comes with the inverter for those cloudy days.

The other option is to get a grid tie inverter (and panels) that output what the pool needs while the sun is out. This is more efficient than the first option since all of the solar is used. It also ensures the pump runs on cloudy days (even if using the grid).

I currently have a hybrid of the two above since I run my pump 24/7 due to the amount of dirt that gets in it. I live rural and we are in a drought so a lot of dust gets in it. I run the pump off a battery bank during the night, then I use a auto transfer switch (set up in reverse) that switches to the grid during the day. I have a second bank of panels that power a small grid tie inverter during the day to offset the pump. I still use some grid power, but not enough to care about.

 

[HackNFly]

Well, I had to return the previous pump, it had the plastic collar broken and the pv glands were too, and I couldn't get in contact with the manufacturer. Back to Amazon it goes.

I looked for a replacement and found this one:

VEVOR Pool Pump Swimming Pool Pump 72V DC/900W Solar Water Pump 62 FT/92 GPM | VEVOR US

Discover VEVOR Pool Pump Swimming Pool Pump 72V DC/900W Solar Water Pump 62 FT/92 GPM, Swimming Pool Pump and Strong Motor at lowest price, 2days delivery, 30days returns.

www.vevor.com

I wanted to check how reliable they were so I sent a message to their customer support and got a message back saying they fully support their products for a year.

It's half the cost of the one I ordered from Amazon, so we'll see.

 

[A.Justice]

Well, I had to return the previous pump, it had the plastic collar broken and the pv glands were too, and I couldn't get in contact with the manufacturer. Back to Amazon it goes.

I looked for a replacement and found this one:

VEVOR Pool Pump Swimming Pool Pump 72V DC/900W Solar Water Pump 62 FT/92 GPM | VEVOR US

Discover VEVOR Pool Pump Swimming Pool Pump 72V DC/900W Solar Water Pump 62 FT/92 GPM, Swimming Pool Pump and Strong Motor at lowest price, 2days delivery, 30days returns.

www.vevor.com

I wanted to check how reliable they were so I sent a message to their customer support and got a message back saying they fully support their products for a year.

It's half the cost of the one I ordered from Amazon, so we'll see.

You definitely get what you pay for when it comes to pool pumps.

 

[tomy2]

Well, I had to return the previous pump, it had the plastic collar broken and the pv glands were too, and I couldn't get in contact with the manufacturer. Back to Amazon it goes.

I looked for a replacement and found this one:

VEVOR Pool Pump Swimming Pool Pump 72V DC/900W Solar Water Pump 62 FT/92 GPM | VEVOR US

Discover VEVOR Pool Pump Swimming Pool Pump 72V DC/900W Solar Water Pump 62 FT/92 GPM, Swimming Pool Pump and Strong Motor at lowest price, 2days delivery, 30days returns.

www.vevor.com

I wanted to check how reliable they were so I sent a message to their customer support and got a message back saying they fully support their products for a year.

It's half the cost of the one I ordered from Amazon, so we'll see.

let me know how the second one works out. I have to redo the pool deck before I add water. anybody used any of the concrete re-newing products with success?

 

[A.Justice]

let me know how the second one works out. I have to redo the pool deck before I add water. anybody used any of the concrete re-newing products with success?

I've done acid washing before, but it can be hit or miss depending on the specifics of your concrete. The company I used to work for actually had stopped doing them because some customers expectations were completely unrealistic.

I normally power wash every couple of years, and if you want to really get it clean, use a push brush with soap and water to scrub the deck down first. I only acid wash if a customer understands that the results may not be great, but is willing to take the risk anyway.

I've never personally used a concrete sealant, but I've seen them used with great results.

 

[Browneye]

let me know how the second one works out. I have to redo the pool deck before I add water. anybody used any of the concrete re-newing products with success?

Pool remodel about twelve years ago, new tile and plaster - 3M quartz. They wanted about twenty grand to do the decks, which had some cracks in them. So they textured and coated, cut irregular cut lines to blend in with the cracks, and textured a fake rock coping.
The coping needs to be re-painted/dyed and recoated with acrylic, and the drive hasn't held up as well as the pool deck, but gee, for the couple of grand I spent on the decks and driveway, it has been phenomenal.