Green Pools are Great

SwimmerHere’s a summer riddle for you: What’s clear and fresh and very clean, all blue but still completely green? If you guessed a swimming pool, you’re right. But what’s green about a clean pool? The green isn’t from algae but from the energy saved by using a variable-speed pool pump.

Most swimming pools use a significant amount of energy. First of all, it just takes a lot of power to pump water and a typical pool has many thousands of gallons to filter each day. Many pumps are set to run much longer than necessary to keep the pool water clean and healthy. Some even have broken timers (or no timers at all) that allow the pump to run 24/7. This is a very expensive practice that takes a toll on the environment as well as your bank account.

Even with properly functioning timers, older single-speed pumps use a lot more energy than newer two-speed or variable-speed pumps. The only way to control a single-speed pump is to turn it on or off. As you would expect, variable-speed pumps can operate at several speeds, from full on to slow and easy. Slower speeds use a lot less energy but there are still times during the daily cycle when more pumping power is needed. Matching the demands of the pool with the speed of the pump is more efficient and saves money.

Saving money is a very good reason for using a variable speed pump and they can be easily installed on existing pools. Costs vary, but as with many energy efficiency upgrades, it does not take long to recoup the investment. There are also instant rebate incentives from NV Energy, up to $200 for installing an efficient variable-speed pump. According to their website,, there are several benefits to the homeowner. First of all, savings of up to 80% on energy costs can be realized. Variable-speed pumps run cooler and quieter, extending their life. Filters can work more efficiently, keeping pool water more clean, clear and healthy.

As a former pool owner, I can attest to the noise of some single-speed pumps since the one I had drove me crazy at times. As they say, silence is golden, and I would have been very grateful for a quieter pool pump. These new pumps are very quiet. Some variable-speed pumps even include a safety feature to help prevent pool entrapment. Capable of automatically sensing blockage of the drain, the pump’s control system automatically shuts it down. This feature alone can justify the cost for safety-conscious pool owners.

Variable-speed pumps can come with a variety of options including programmable micro-processor control with password protection. Some pumps offer automatic sensing and protection from freezing, overheating, loss of prime and even voltage irregularities. They can be reprogrammed to adapt to changes in pool equipment. For pools with water features, programmable pumps can offer different modes of operation to easily change the sights and sounds of your pool.

Some manufacturers have savings calculators on their websites. I compared two of them, using the following assumptions for an existing pool: 20,000 gallon pool with a single-speed, 2 HP pump running 10 hours per day all year with an electricity rate of 12 cents per kilowatt-hour. The Hayward calculator estimated yearly savings of $643.41 and a payback of 20 months (and only four months for the less costly two-speed option). The Pentair calculator estimated a range of yearly savings from $259.57 to $888.70 depending on chosen water turnover rates.

While actual savings will vary, there is no doubt that using an efficient pool pump makes good financial and environmental sense, especially when coupled with the rebates from NV Energy. There are other options as well. A simple pool cover can reduce evaporation losses and chemical use while keeping temperatures comfortable. Solar pool heating systems can save thousands of dollars and tons of CO2.

As we enter pool season, think about what you can do to keep your pool clear, blue, clean and most of all – green! It should no longer be a riddle.

Green Living column for Thursday, May 21, 2009, published in the Las Vegas Review Journal: “Pump up the green factor at variable speeds”

Additional Resources: