Variable Speed Pool Pump efficiency

[Brian Kent]

Since our electric rates just jumped up, we are looking for new ways to save.

We have a 1.5 HP single speed pool pump for an in ground pool. It runs 6 hours per day.

Does anyone have experience or expertise to know how much electricity we could save by getting a variable speed pool pump?

We pay .41 per Kwh for the tier two energy costs.

Thank you for your help

[Greg R Bradley]

I converted my 2hp single speed to a Pentair Intelliflow VS in 2008:

https://pentairpool.com/en/products/pumps/intelliflo%20vs%20svrs%20variable%20speed%20pumps

The pool places near me wanted about $2000-2300 installed at the time. I bought it from Poolsonly.com for $1264 and installed it myself. There was a $300 rebate from SCE at the time. It was very new at the time so I assume they have come down. It runs a program and figures out the most efficient speed for various functions, particularly important for me as I have a large pool with piping that would be considered small today. It calculates current draw and water flow and figures out how to get the most flow per watt. One HUGE benefit is it is quiet, meaning it can run at night. It dropped about $60-80 a month off my electric bill June-Sept. Much of this is it kept me from hitting the higher price tiers.

I was guessing that it payed for the $964 net cost in two years or so.

[Mike Henderson]

Instead of changing the pool pump, consider installing solar panels. You can generate enough electricity to keep yourself in tier 1 and lower electricity rates. I think you still get a 30% federal tax rebate. That means you take 30% of what you paid for the solar install and deduct it from your federal tax.

Mike

[David T gray]

Pentair Intelliflow VS is nice have one of these also and 14kw of solar panels. the old pump i had ran 8 hours a day at around 2kwh the pentair runs 14 hours a day and uses .15kwh do the math you will see the vs pumps are worth it pretty quickly had it for about 5 years now im sure its payed for its self at least twice over by now doing the math standard pump vs VS pump $584/year vs $76/year @ $.10kwh so yeah u could buy a new one every 2 years and still make money. my house is 6500sf in the middle of texas so i find every little bit helps with the electric bill. luckily Austin energy paid for 1/2 of the solar panel cost then 30% off from the fed. Austin energy also paid to replace 2 water heaters with heat pump ones when i bought the house the average electric bill was $600 in the middle of summer now its $150 at the highest and some months i get money from them in credit. ohh they also paid to install heat pumps on 4 ac units so that helps in winter. i pay insane property tax don't move here we are full.

[Lee Schierer]

Changing the speed of your pool pump will affect how well your pump moves the water through your filters. The slower it runs the less water that it will move. The best way to save energy on a pool pump is to determine how long the pump needs to run at full speed to adequately clean the pool. Then set up a timer so that the pump only runs for that length of time. You may want it to run more than once per day when the pool sees a lot of use.

[David T gray]

Changing the speed of your pool pump will affect how well your pump moves the water through your filters. The slower it runs the less water that it will move. The best way to save energy on a pool pump is to determine how long the pump needs to run at full speed to adequately clean the pool. Then set up a timer so that the pump only runs for that length of time. You may want it to run more than once per day when the pool sees a lot of use.

nah thats so so very wrong at 1400 rpm my pump uses 150w at 2000rpm it uses 700ish and at 3000 it uses 2.4k watts yet it still pushes 60% of what it does @ 3000 rpm.

[Lee Schierer]

nah thats so so very wrong at 1400 rpm my pump uses 150w at 2000rpm it uses 700ish and at 3000 it uses 2.4k watts yet it still pushes 60% of what it does @ 3000 rpm.

What Hp is your motor? For any given size pump, a pump run at half the speed of another will produce half the flow and one quarter the head, so your actual flow through your system may not be what you think.

[Greg R Bradley]

My experience matches David's. The Intelliflow shows you GPM, RPM, and Wattage. The GPM is clearly close to reality as I can tell by how fast it fills an empty spa and how fast it runs a cleaner. As the system runs its test of your pool, it clearly is much more efficient up to a certain speed. Above that it takes progressively a lot more wattage to move a lot less water. Mine behaves differently than my neighbor with the same pump and larger plumbing. Mine takes almost double the power to move 20GPM as it does to move 15GPM. It does clean the pool a bit faster at 20GPM but it is much cheaper to run it a bit longer at 15GPM. My neighbors pool takes only 35% more to run 20GPM than 15GPM. This is almost exactly what you would expect if the system flows freely, 33% more water flow for slightly more than 33% more power.

You can tell how dirty the filter is by how much wattage is required for it to move 15GPM of water.

[Bill Miltner]

Changing the speed of your pool pump will affect how well your pump moves the water through your filters. The slower it runs the less water that it will move. The best way to save energy on a pool pump is to determine how long the pump needs to run at full speed to adequately clean the pool. Then set up a timer so that the pump only runs for that length of time. You may want it to run more than once per day when the pool sees a lot of use.

I have to agree with the posters above. To the pool it matters little if it take twice as long to push say, 25,000 gallons, at 1600 rpm versus 3200. But the wattage required to run the pump at 1600 rpm is less than 25% what it uses at 3200rpm (my pool, every pool is different). In my case the savings is >50% in kwh.