How to calculate a pump's electricity usage?

[frogkick]

I just got my first electric bill after the pool was installed. In June 2016 I used 1100 KWH and in June 2017 I used 1700 KWH. I verified there was no significant increase in outdoor temperature from last year to this year and I also replaced my very vintage AC with a 16 SEER unit somewhere in between those so I was surprised to see my energy usage increase so much. Could all this energy be going to the pump?

I have a 3HP Pentair Intelliflo VS. The current settings (what the pool guys programmed) run it on 2100 RPM for 8 hours and 2800 RPMs for 4 hours. Is someone able to calculate how much energy that would consume?

Thank you! Let me know if you need more info!

 

[mas985]

I can give you a ball park.

At 2100 RPM, the pump uses about 650 watts and at 2800 RPM, about 1500 watts. This would result in about 11 kwh per day or about 336 kwh per month.

My first question is why are you running at such high RPM and for so long? If you reduced your run time to 4 hours per day at 1000 RPM, your monthly usage would go down to 12 kwh.

Also there are some spreadsheet tools in my signature to get a bit more accurate.

 

[pooldv]

The pump display will tell you how many watts it is using. I run mine at 1100 rpm and it uses 150 watts. At 10.25c/kWh you can run it 8 hours a day for less than 4 bucks a month.

 

[frogkick]

My first question is why are you running at such high RPM and for so long? If you reduced your run time to 4 hours per day at 1000 RPM, your monthly usage would go down to 12 kwh.

Well, that's where the pool guys set it up for me and I don't know enough to change it to something else. 2100 RPM is as low as the pump can go without the water feature looking sad. I do live in a warm climate with 100 degree days and water temperature of 91 today. I'm under the impression that means my water needs to circulate more than in a cooler climate, right?

 

[pooldv]

When running the pump to skim and filter the water feature should be off. That water feature will push you pH up and up and up creating a high potential for calcium scaling in the pool, Pool School - Calcium Scaling. Only run waterfalls, bubbles, etc when people are around to look at them.

3 or 4 hours of skimming and filtering at 1100 or 1200 rpm is probably plenty. More here, Pool School - Determine Pump Run Time

Warm water and hot climate means you need higher CYA and more chlorine.

 

[frogkick]

My water feature is a sheer descent. Will that still increase calcium even though it's not touching rock?

For now, I'm still building my CYA (currently rounding up to 30 per the disappearing dot test), so I've been using pucks to add both chlorine and CYA since I have them. Those pucks are fed in at the equipment pad and won't be getting to the pool water if the pump is off. Would 4 hours be sufficient to chlorinate the water in that case?

 

[pooldv]

Water features increase pH, not CH. They increase pH through aeration, anything that breaks the surface of the water will increase pH. High pH increases the likelihood of calcium scale developing in your pool. Unless you diligently add muriatic acid to keep pH at 7.6-7.8.

 

[JamesW]

One problem with a tab feeder is that the tabs continue to dissolve in the feeder even when there is no flow.

This creates very high chlorine levels and very low ph in the feeder.

The corrosive mix migrates from the feeder into the equipment destroying everything it touches.

With a tab feeder, I would minimize or eliminate pump downtime.

With a VS pump, you can run 24/7 at low speed for very low cost.

 

[frogkick]

Good to know. My pool just has one pump so the way to turn on and off the water feature is a lever at the equipment pad. While that's clearly not a tremendous hardship, I love the automation of the rest of my pool. Is there anything I could add that would allow me to specifically turn on and off the water feature from the Pentair app or would that require a major plumbing change...in which case I'll stick to the lever.

 

[rphpool]

you can replace that one valve with a automation valve. I did not see what type of automation you have in sig, ET8??

 

[frogkick]

Oh, I don't think I have anything that fancy. I can just turn things on and off with an app, which I like. Since I can turn the pool on and off, the lights on and off, it would be great if I could also turn my water feature on and off with the app. Can that be done if I add an automation valve?

Also, I have a 3/4 HP booster pump for the Pentair cleaner that has been running 4 hours per day, but won't need to now that I have a robot. Is there anyway to guess how much electricity that booster pump consumed for 4 hours/day?

 

[mas985]

It uses close to 1500 watts or close to 6 kwh per day, or 180 kwh per month.