New owner, astronomical power bills, need help sizing a variable speed pump

doctat

New member
Mar 15, 2017
2
Pasadena, CA
#1
Hey all,

Bought my first house, came with my first pool. My electricity bill is absolutely ridiculous, most likely due to the pool pump running all the time.

Previous house owner was loaded, so I don't think this phased him at all, but I need a solution.

Anyway, have been doing homework, here is some background.

I have what I think is a 15,000 gal pool (estimated based on dimensions, it's a weird shape), with a spa that is elevated which dumps water over a fall into the main pool.

There is a Jandy SHPF-2.0 Stealth primary pump, a secondary pump for a few waterfalls (which we rarely run), and a heater. Everything is controlled via an Aqualink RS panel, which has a small remote panel in the house.

The previous owner had the pump set to run from 9am until 6pm every day. Being a know-nothing noob, we just assumed this was correct and let it roll. A few months later and a handful of massive power bills have led me to a lot of research.

I installed a flow meter in one of the check valves, and looks like the pump is doing about 70gpm when running. So that's about 3.6 hrs run time needed to circulate the entire pool, so I dialed the run time for the main pump down to that run time, and am hoping that solves a majority of the issue. However, I'm very interested in getting a variable speed pump, to reduce this power consumption even further, since we're gonna be in this house for many years.

Looking at specs on Jandy pumps at this URL: http://www.jandy.com/~/media/zodiac/global/downloads/sa/sa6228.pdf

If I'm reading this correctly, my SHPF-2.0 pump, pushing about 70gpm, it would appear as if my Feet of Head is about 80' or so, which I gather is relatively high. Without knowing any of the details on the pool piping, my guess is this is mainly due to the pump having to send water up to a higher elevation to the spa, which then overflows via the waterfall into the main pool.

Anyway, in researching what type of variable speed pump might be suitable, via that same link listed above, I'm concerned that these variable speed pumps, when running at a lower RPM, will not be able to accommodate that amount of Feet of Head, and that I may be stuck having to run a high HP pump to circulate the water properly.

Where I live (Pasadena, CA), the city will do a rebate on one model of Jandy pumps (I'm looking at them, mainly because that's what's hooked up there now) which is the VS FloPro pump.

However, looking again at that link, it would appear to accommodate 80 Feet of Head, I would need to install the larger VSFHP270 model, which has similar THP to the current pump (2.7) and would still need to run it at high speed, for a relatively similar amount of time, to be able to circulate the pool properly - which I would imagine that would end up being a complete wash, power-savings-wise, and hence not be worth the investment.

I guess my main question is, is there a minimum speed at which you must run a pump at, to overcome the Feet of Head metric - i.e. if I install a variable speed pump, will I still need to run the thing at high speed, to push the water through the pipes effectively? Or does that not really factor in, and I could indeed run a pump at lower speed, for a longer amount of time, and it would indeed be able to circulate the water correctly, but at a lower overall power consumption?

Apologies in advance if I'm being a complete dork here, and missing something that should be obvious.

Any help much appreciated!
 

CJadamec

TFP Expert
Apr 29, 2016
2,194
Quaker Hill, CT
#2
The 9 to 6 run time isn't all that crazy that's about what I run my pool to maintain temp with my heat pump also to keep the top skimmed clean. That many hours on a single speed pump that big is definitely running your electric bill up tho. Since you can get a rebate for a VS pump and you are paying CA rates for power the cost premium for the VS over a 2-speed is probably worth it.
When it comes to which one, if you want to get the larger hp270 model go for it. It will actually be cheaper to run than the smaller model. I would pick the model pump that works the best with your automation that you have already installed.
When it comes to setting the rpm for general circulation and skimming you go as low as you can and still get good skimming action. 1200-1500rpm is a good starting guess.
For heating you find the min rpm that the heater flow switch allows you to run and then add about 500 rpm to that number. If you have a gas heater you can bump that rate up for quicker heating if you want to. 1200-2000rpm
If you are using a suction or pressure side cleaner pick a rpm that gives you good cleaning generally on the higher side. 2000+rpm
Those number are a guess but its a decent place to start.

As for cost of running at 1200rpm a VS pump will use roughly 200-300 watts. At half speed roughly 1750rpm you will use roughly 750-1000 watts. At full rpm which is the same amp draw as your current single speed pump you are looking at around 3000 watts.
 

madwil

Well-known member
May 2, 2011
370
lebanon tn
#3
Can you bypass spa and water features? The spa wouldn't need to circulate that much, just enough to refresh it and the same for piping to features. Then a lower setting could easily turn ov r the main pool
 

JamesW

TFP Expert
Mar 2, 2011
12,819
#4
Feet of head depends on flow rate. As you drop down flow rate, feet of head drops exponentially. 1/2 flow = 1/4 feet of head. 1/3 flow = 1/9 feet of head.

Power drops exponentially as well. 1/2 flow = 1/8 power. 1/3 flow = 1/27 power (theoretically).

For example, if your pressure is 18 psi and you're using 2700 watts at full speed, your pressure would be 2 psi and your power usage would be 100 watts at 1/3 speed.

Pushing water into the elevated spa only has a minor effect on feet of head. The feet of head is determined by how high the spa water surface is above the pool water surface. For example, 3 feet higher adds 3 feet head. That's static and independent of flow rate.

Get the bigger pump and you should be able to run it at low speed most of the time and save lots of money.
 

Nursenini

LifeTime Supporter
TFP Guide
Sep 22, 2015
2,122
Bixby, Ok
#5
Besides all the advice on pump run time, etc., you might check with your power company about an average monthly payment plan. That's what we have here with both our electric and gas. This way we have small fluctuations in our monthly bills but no great spikes for heating in the winter and cooling in the summer. Makes it much easier to budget and manage the times of extreme heat and cold, and the times I used the heater for the pool or the spa did not impact my bill since it's all averaged.
 

JohnT

Admin
Mod Squad
TFP Expert
Apr 4, 2007
9,459
SW Indiana
#6
I suspect you will be disappointed in the savings. That motor consumes about 2300W maximum. Running for 9 hours a day that is 20.7KWH.

The most expensive rate I can find online for Pasadena is $0.14750 per KWH. That means your pump's maximum cost right now is $3 a day or about $90 a month.

Going to a variable speed pump will probably save about half that. Cutting your run time will save you about $10 per month for every hour you cut the run time back.

That's not to say it isn't good to reduce your usage, but nothing you are going to do, including removing the pool, is going to reduce an astronomical bill to reasonable.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,488
Tucson, AZ
#7
I suspect you will be disappointed in the savings. That motor consumes about 2300W maximum. Running for 9 hours a day that is 20.7KWH.

The most expensive rate I can find online for Pasadena is $0.14750 per KWH. That means your pump's maximum cost right now is $3 a day or about $90 a month.

Going to a variable speed pump will probably save about half that. Cutting your run time will save you about $10 per month for every hour you cut the run time back.

That's not to say it isn't good to reduce your usage, but nothing you are going to do, including removing the pool, is going to reduce an astronomical bill to reasonable.
It's a lot higher than $0.14/KWh...a lot ;)

California not only has tiered usage but rates vary for season as well. For 0-100% of baseline, the total charges are closer to $0.20/KWh. For 101%-400% of baseline, the charges can easily go up to $0.27/KWh and over 400% of baseline it's almost $0.40/KWh. Baselines are determined by maximum number of KWh per day and it is region specific but the baseline in the summer can be as low as 8KWh/day to as high as 20KWh/day.

So his single speed pump running at nearly 20.7KWh will almost always put the OP into the 2nd tier of usage. Couple that with running A/C's and other appliances and your typical Californian is paying well over $0.30/KWh.....one of the many reasons why I was happy to move out of the state....
 

Sammy2

Well-known member
Aug 30, 2016
378
Riverside, CA
#8
Local Public Utilities, especially those established long ago generally have lower rates than the Privately owned utilities such as Edison and PG&E.

Where I'm at RPU has the following tiers:

Tier1 is $.1035/kWh
Tier2 is $.1646/kWh
Tier3 is $.1867/kWh

In the summer from June until August these break as follows:

Tier1 up to 750kWh
Tier2 751kWh to 1,500kWh
Tier3 greater than 1,500 kWh

The TOO long winter tiers are as follows:

Tier1 up to 350kWh
Tier2 351kWh to 750kWh
Tier3 greater than 750 kWh

We are too often in the winter break points it would seem. I don't even know why they have it but I guess it helps a little bit.

Pool owners also get a $5/month credit for agreeing to only run filtration pumps between 8pm and noon (off peak hours). I do this to lower my bill a smidgen.
 

Sammy2

Well-known member
Aug 30, 2016
378
Riverside, CA
#9
@doctat

Don't get stuck on using a particular brand because that is what you have now. Pick the pump that best suits your demands and needs. I'm in process of replacing a pump due to the bearings getting real, real load right now. I'm coming to realize that I should have done this when we bought the house three years ago as the pump would have already paid for itself but now that it is a necessity it will happen.

There's a lot to consider besides brand name. I've learned a lot from the experts on this forum about pumps and pump sizing in the last 24 to 48 hours. You need to come back and review the responses you have already and pose follow-up questions so you can get the right pump for your needs.
 

doctat

New member
Mar 15, 2017
2
Pasadena, CA
#10
Thank you everyone very much for the replies - lots of good information here!

I am still doing homework on all this, will report back with more info soon.

Thanks very much again to all of you!
 

kevreh

In The Industry
Jun 2, 2007
412
Annandale, VA
#11
In summer I run my pump from 10am-4pm. Only to 6pm if I want to benefit from the solar warm up via my panels. Going from 9-6 to this would save you about 30%. Any I have a number of tree's in my yard which require minimal cleaning from my Polaris cleaner with booster pump. I have a two speed pump, but figure the lower speed would mean I would just run the pump longer to get same results.
 

jdoty1977

Active member
May 25, 2016
38
Little Elm TX
#12
Just curious if this is a salt water pool. If you are using the pump to create Chlorine from salt then that is a good reason to run the pump so long. Just didn't want you to overlook this point as I think it is certainly something to consider when talking about pump speeds and run-times.
 

Sammy2

Well-known member
Aug 30, 2016
378
Riverside, CA
#13
Just curious if this is a salt water pool. If you are using the pump to create Chlorine from salt then that is a good reason to run the pump so long. Just didn't want you to overlook this point as I think it is certainly something to consider when talking about pump speeds and run-times.
I've been having quite the conversation about just this topic. It seems that it might not need as much more of a run time as one might think but using the spreadsheets provided by @mas985 even then running the pump longer still costs less money than short runs at full speed.