Pool and spa
The energy used to operate the cleaning and filtering equipment of a typical pool for one swimming season can equal the energy used to power the average home for the same period. SMUD has suggestions to save you energy and money.
Running filtration equipment
You can help reduce peak-period power demand and bring down power-supply costs for our whole community by running filtration equipment before 4 p.m. and after 7 p.m.
Bigger may not be better
Pools are commonly equipped with larger pumps than needed. Replacing a standard pump and motor assembly with a high-efficiency unit 1/4 or 1/2-horsepower smaller, or better yet with a multi-speed pump, will yield impressive savings in electricity costs. And you will see virtually no reduction in cleaning effectiveness.
Replacing an oversized pool pump -- even one in good working order -- with a smaller, energy-efficient pump is an investment that usually pays for itself in just two to four years.
Running a pump at half speed reduces power use to one-quarter of that required for full speed. The pump will need to run twice as long at low speed to filter the same amount of water, but you will still save money. Running the pump for 16 hours on low speed costs about half as much as running eight hours on high speed.
An added benefit of running a multi-speed pump on low speed is that it will make very little noise. Just a low hum.
With a multi-speed pump, you can still run it on full speed for short periods if necessary, for backwashing or vacuuming, for example.
Cost of operation
Here's a real-life comparison of operating costs:
Pool No. 1, the traditional approach: $51.90 per month
This 25,000 gallon pool has a normal 1.5 horsepower pool pump. It runs eight hours per day. It pumps about 80 gallons per minute, which means that it circulates 38,400 gallons each day. The pump draws 9.0 amps at 240 volts. At a cost of 10 cents per kilowatt-hour, that translates to a cost of $1.73 per day or $51.90 per month to operate the pool.
Pool No. 2, the multi-speed approach: $19.50 per month
This 25,000 gallon pool has a multi-speed 1.5 horsepower pool pump. It runs 12 hours per day in low speed. In low speed it pumps about 40 gallons per minute, which means that it circulates 28,800 gallons each day. (Remember that the pool only needs to turn the water over once each day). The pump draws 2.25 amps at 240 volts in low speed. At a cost of 10 cents per kilowatt-hour, that translates to a cost of $0.65 per day or $19.50 per month to operate the pool.
The multi-speed pump provides just the circulation your pool needs at a fraction of the cost. These figures are for comparison only and actual savings will depend on rate structure and use.
Keeping the pool circulating a longer period of time each day has a couple of advantages:
- The longer periods of circulation will help to reduce algae.
- If you have a salt system, you can run the system many more hours per day and get increased chlorine production if needed.
What about solar systems?
When a pool has a solar system mounted on the roof, a multi-speed pump may not be the answer. With a solar system, it is often better to use a smaller single speed pump, such as a 3/4 horsepower pump that will give you adequate lift at all times.
A good pool cover keeps water temperatures about 10 degrees higher and reduces evaporation of water and chemicals by about 70 percent. Your pool stays warmer -- and cleaner -- as energy use and equipment wear are minimized.
- Lower the temperature by about 3 degrees. This saves 5 to 10 percent in heating costs.
- Run the air jets only when using the spa. The cooling effect of the air bubbles counteracts the energy used to heat the water.
- Keep the spa covered until you're ready to use it. Heat loss is money wasted.
- Add a floating thermal blanket to the rigid cover used with most spas. The added layer conserves heat and reduces evaporation.
Free time clock trippers: SMUD provides time clock trippers for free. Call us and let us know the make of your time clock or the color of the face.
For more information on pool and spa efficiency, call SMUD at 1-888-742-SMUD (7683).