Would a variable speed pump save a lot on electricity?

[unit9419]

I have a 20,000 gallon pool with infinity edge so I run the pump all the time otherwise it just doesn't "look" right. But electricity is extremely expensive here in Belize CA. I've been reading that Pentair variable speed pumps can save a ton on electricity. But t would apply to me given the amount of flow needed to keep the infinity edge pouring over. Hope my question makes sense?

 

[unit9419]

I just found a similar thread. Doesn't sound like variable speed is going to help much due to the infinity edge flow rate. To save $ I just need to run it less.

 

[1poolman1]

I just found a similar thread. Doesn't sound like variable speed is going to help much due to the infinity edge flow rate. To save $ I just need to run it less.

Do you need the infinity edge to operate at all times? Is the suction for the filter system in the catch basin? If not only run the speed needed for the effect when you want it and allow the lower speeds to keep the pool clean and chemicals mixed. The energy savings are tremendous when done that way.

 

[Newdude]

For reference, my SWG works at 700 RPMs with the pump pulling 35W. 1200 skims well at 110W. I splurge all the way to 1500 RPM /200W because I like the look of the water moving more.

Nothing that floats has a chance to get waterlogged and sink for 12+ hours before the pump comes on again.

I've never *once* wondered if I was filtering enough.

The SWG tops my FC off around the clock.

I cannot reccomend 24/7 enough at low enough RPMs that the function you are trying to achive still works.

Some heaters or features need 1800 to 2200 RPMs in the 400w to 800w range. Its still a far cry from the 3450 RPM / 1800W of full throttle or a single speed.

 

[BDY]

What flow rate does the edge need?

See if the 3hp pentair pump will move enough flow at lower speeds. My 3hp 011056 moves 20 GPM for me at 1000 rpm.

The larger pumps are more efficient at lower speeds in general…

 

[Jimrahbe]

unit,

I'm a little confused why you need a lot of flow to make your neg edge work..

I understand that you might want to see a lot of flow over the edge, but even if the flow is low, the excess water has to go over the edge.

Can you explain why you need a high flow to make the edge work?

Thanks,

Jim R.

 

[mas985]

Often times the reason an infinity edge doesn't "look right" at lower flow rates is because parts of the edge are too far out of level. So lower flow rates only wet part of the edge. Is the issue an uneven edge overflow?

The other reason could be that there is a main drain and/or skimmer involved that is stealing flow rate from the edge. The solution here is to shut off those suction ports as they are not needed when the edge is being used. Does the pool have a main drain and/or skimmer?

 

[unit9419]

unit,

I'm a little confused why you need a lot of flow to make your neg edge work..

I understand that you might want to see a lot of flow over the edge, but even if the flow is low, the excess water has to go over the edge.

Can you explain why you need a high flow to make the edge work?

Thanks,

Jim R.

Wow, great question! I guess I just assumed it would take a lot of flow. I will have to think this through. The pump pulls from.

Often times the reason an infinity edge doesn't "look right" at lower flow rates is because parts of the edge are too far out of level. So lower flow rates only wet part of the edge. Is the issue an uneven edge overflow?

The other reason could be that there is a main drain and/or skimmer involved that is stealing flow rate from the edge. The solution here is to shut off those suction ports as they are not needed when the edge is being used. Does the pool have a main drain and/or skimmer?

That's very interesting about not need to use the those port bottom and skimmer ports. The pool has drains on the bottom and 2 skimmers. I thought it was important to have at least some water circulating through those in order to be filtering the entire water column. If I can safely close those off then I could certainly reduce the flow and keep the edge looking nice.

The edge was built well. It's level. There's just once place where the prevailing wind tends to push water away and I get a salt build up on that corner of the edge.

 

[unit9419]

Do you need the infinity edge to operate at all times? Is the suction for the filter system in the catch basin? If not only run the speed needed for the effect when you want it and allow the lower speeds to keep the pool clean and chemicals mixed. The energy savings are tremendous when done that way.

The pump pulls from the skimmers, bottom drain and catch basin. There are valves on all three of those where I can control the amount. How important is it to be pulling water from the bottom drain to ensure good filtration of the entire water column in the pool. We do of course vacuum it

 

[mas985]

Mains drains do almost nothing when it comes to cleaning and circulation so turning them off won't change anything. Many pools are now built without them for both safety issues and decrease the risk of bottom leaks. I have a MD but leave it off most of the time so I can run my VS pump at the lowest RPM possible while still maintaining good skimming action.

Also, the infinity edge acts as a huge skimmer so you really don't need another skimmer running at the same time unless debris is getting hung up on the edge.

Adding more suction ports just increases the flow rate requirement without much of a benefit.

If you have automation and valve actuators, you could setup the system to automatically shut off those valves when using the infinity edge.

 

[skimmerswimmer]

I used to have 1 HP single speed pump that used about 1500 watts. I switched to a 3HP variable speed pump and it uses around 200 watts at 1500 RPM. This is 1.2 kwh x 12 hours savings = about 14kW/day (about $3.50 per day) savings during the pool season. I run the pool from April to October, so this comes to about $800 savings per season.