When it comes to reducing the cost of running your swimming pool, remember that bigger isn’t always better – particularly when it comes to pool pumps. A recent study by the Center for Energy Conservation at Florida Atlantic University found that pool owners in Florida could save as much as 75% of their original pumping bill simply by combining two energy conservation measures – downsizing their pump and running it less often. Best of all, they were able to do so without sacrificing the quality of the water in which their family swam.
Please note that the numbers mentioned in this article apply to a typical 10,000-gallon pool that does not have a spa or additional water feature attached. How large is that? When we’re talking about above ground pools with walls that average 52″ tall, that would be a 15′ by 30′ oval or a bit larger than a 21′ round pool. When translating that number to an inground pool with an average depth of 42″, that would be a little larger than a 12′ x 24′ rectangle. Also bear in mind that this advice does not apply to the growing number of systems that use salt chlorine generators. Since these generators only create chlorine when the pump is running, owners of these systems will need to run the pump longer than the recommendations below to maintain a proper chlorine balance in their pools.
What size is right for you? The Florida study found that a ¾-horsepower or smaller pump generally works well for most residential pools. (Their recommendation was ½ horsepower per 10,000 gallons.) You’ll want to check with your pool’s designer or manufacturer to be certain this will work in your particular case. You might be able to opt for an even smaller pump if you follow some tips from the U.S. Department of Energy. They recommend substituting a larger filter rated to at least 50% higher than the pool’s design flow rate. When you are designing or upfitting a pool, the DOE recommends increasing the diameter and/or decreasing the length of any pipes and opting for flexible pipes or more gradual 45-degree (instead of the traditional 90-degree) elbow pipes. Both options reduce the resistance your pool’s circulation system has to deal with, which in turn can reduce your pump’s energy usage by up to a surprising 40 percent.
How much is too much? When you are constantly using your pool in the summer, there’s an understandable temptation to run the pool pump more often than you need. Studies have shown that you can efficiently clean your pool by reducing your filtration time to just three hours a day or less. How do you do that? Start by adding a timer to control your pump’s cycling. Running several short cycles actually keeps the pool cleaner than running one long one, because it allows the pump to keep up with debris. Take just a few minutes to skim large debris by hand and to clear intake grates of debris. Your pump has to work harder – and thus, burn more energy – when the drains are clogged. If your water still doesn’t appear clean, the DOE recommends increases your cycling in half-hour increments until you find the time that works best for your individual situation. The Florida study found that simply reducing the time your pool pump is on saved as much as 60%.
As we mentioned initially, it was the combination of these two simple steps – using a smaller pump and running it less often – that had the most impact – up to a whopping 75% of participants’ original pumping bill. View our previous article on common pool myths for more practical advise on maintaining your pool. For more great tips on saving energy during the summer and at any time of the year, visit www.energysavers.gov.