Swimming Pool Blog
How to save money at the pool pump
by Rob Cox, August 30, 2010
With energy costs as high as they are now, it seems the most eco friendly thing you can do with your pool is to reduce it's energy consumption or demand. The largest energy hog on the pool equipment pad is the pool pump, and many state utilities are now offering incentive energy rebates to pool owners to reduce their pool pump energy use. even without a rebate, you can make changes to your circulation system or methods and save big on your electric bill.
PG& E, in California reports that a pool pump can account for 20% or more of a home electrical bill. Pumps are also running during peak usage hours. Savings of $500 per year are not uncommon for many pool owners who switch to new two speed or variable speed pumps. Paybacks on these pricey pool pumps can come in as little as 3 years.
There are things that you can do however, to reduce your energy consumption, without switching pool pumps, to "Save Money at the Pump".
1. Use a smaller horsepower pump and/or a larger filter. Many pumps installed are just too powerful. We have something of a V8 mentality in the US - we want the biggest, baddest engine. Something that really "moves some water"! This can cause filtration problems, if the filter is pushing the water too fast through the filter and also consumes a lot of amperage. The more the horsepower, the higher the amp draw. Amps are what you really pay for on your electrical bill.
Using a smaller pump, is that possible? Probably - look at your pool pump flow chart. Find the line that represents your horsepower, and assume a set amount of resistance, in feet of head. Then do the math. You will divide your pool gallonage by the flow rate of the pump horsepower (at a set amount of resistance) as measured in gallons per minute. If a smaller horsepower can "turn over" all of the water in your pool in 480 minutes ( 8 hours ), then it can be done.
Selecting a pump with higher flow characteristics can do the job for you as well. Not all 1 hp pumps are the same. Pumps vary in the amount of water they move. A 1 hp Northstar can produce more than twice the water flow as the 1 hp Superpump. A 3/4hp Whisperflo can produce as much flow in most cases, as a 1.5hp Pinnacle pump.
A way to do it easier is to increase the size of the filter. Having a larger filter provides more square footage for the pumped water to be filtered, at a lower pressure. Lower pressure means that your pump is not working as hard. Having a larger filter also assumes that you are filtering more efficiently, and this could allow you to run the pump less often, or fewer hours per day.
2. Run your pump less often. Everyone I know runs their pump too much. And if you have a service company taking care of your pool, they are probably running it as much as possible, which reduces their water problems and chemical usage. I like to run pools with the minimum amount of pool pump run time as possible. It only takes a little experimentation. This will require a pool pump timeclock - don't' rely on your memory to turn a pool pump on and off each day, you are bound to forget.
Begin at 12 hours of filter run time per day. Keep all else constant: pool cleanliness, pool sanitizer level, water balance. If after two weeks time the water quality does not suffer, reduce the pool pump operation time by another two hours. Continue this until you notice the water has lost a sparkle, or begins to look hazy. Then increase the time to the previous threshold.
During very hot times of the year or during periods of active pool use, you may need to add two hours. During the shoulder seasons you can decrease pump run time in the other direction, and during the low season - when the water temps are in the low 60's, you may be able to run the pump as little as 4-6 hours per day.
3. Use a two speed pump. During the 90's, two speed pool pumps became very popular. The idea is to run a two speed pump 24 hours per day, but on low speed for the majority of the time. This keeps circulation constant, to maintain sanitizer levels and prevent dead spots, while the high speed run time keeps the pool clean.
Using a 2 speed pool pump will save money, no doubt - even more if you run it only 12-18 hours per day total. Typically the lower speed is 1/8 hp, and consumes only a very small amount of amperage. Experimentation is key here also - perhaps 4-8 hours on high speed and 8-12 hours on low speed, with seasonal adjustments.
Installing a two speed pool pump requires a two speed timeclock be installed. There is a 4th wire that needs to be run from the clock to a two speed motor. Plan on the extra expenditure of $200 or more on the clock and wiring when installing a two speed pool pump. 2 speed pumps typically cost around 20% more than a single speed pool pump of the same make/model.
4. Use a Variable Speed Pump. The new kids on the block, all major manufacturers are now offering variable speed pool pumps. These pool pumps will save the most electricity possible, because they "dial it in" - meaning, they consume only the power necessary. Programmable to many different speeds and tasks, they produce the kind of hydraulic efficiency found in nuclear subs.
Variable speed pumps can also come standard with other bells and whistles such as SVRS, vacuum release systems, or integration with popular control systems. These pumps come with a price tag starting at $1000, so they're not for everyone, but can be a big money saver on a fancy pool with several water features and cleaning systems.