Environmental Stewardship
Hot Tub and Pool Tips
The Western Washington Chapter of the National Spa and Pool Institute (NSPI) makes these recommendations for efficient use of hot tubs and pools:
Set the hot tub heater thermostat to maintain 102ºF. Some hot tubs have been set to heat water to 104ºF. During the summer, set the temperature below body temperature, about 96ºF.
Shift hot tub water heating to off-peak times. If your hot tub has a timer, you can help reduce peak loads and pressure on utility rates by programming the timer to "off" during peak hours - 6 a.m. to 10 a.m. and 5 p.m. to 9 p.m. If you have a well-insulated, energy efficient hot tub, it will maintain temperature for several hours after the heater is turned off.
Turn down the thermostat when you're on vacation. If you are leaving for an extended period of time and won't use the hot tub for a week or more, turn the heat down or off.
Reduce pumping cycles. Normally filtration cycles for single and two speed pumps are set for four hours. You may be able to reduce the filtration cycles to three hours, twice a day - during off-peak hours. This adjustment should be based on your usage pattern, so you can maintain clear, clean and safe water. If your spa has a low wattage circulation pump - leave it alone, it's designed to run continuously.
Use a foam cover with good insulating qualities. Standard covers have an insulating value of approximately R-12. Keeping a cover in good condition is essential because most heat loss will be through the spa cover. Replace the cover if the interior foam is broken or water-saturated. A water-logged cover will increase energy consumption from heat loss. Make sure the cover and tub lip fit snugly, straps are tied and the cover is latched when the hot tub is not in use. This will reduce heat leakage. To handle the cover more easily and extend its life, consider using a lifting system.
Add a floating blanket. An energy-efficient floating thermal blanket will help retain heat and reduces the amount of moisture building up on the inside of your solid cover. For example, adding a 1/4" closed-cell foam floating blanket under the hard cover can increase the total R-value to 16.
Avoid wasting water. Repair any leaks and adjust jets or use booster pads to adjust your height so you're not sending streams of water on the deck.
Drain the hot tub only when necessary. Hot tubs that are heavily used by bathers should be drained every 3-4 months. When it's time to drain, either drain to a sanitary sewer or use the water for lawn irrigation. Make sure no chemicals have been added for at least 48–72 hours before draining.
Create windbreaks around the hot tub. Cutting wind exposure can reduce heat loss. Privacy panels, landscaping, or fencing can all be effective windbreaks.
Buy only energy-efficient spas and hot tubs. Today, significant improvements in the construction, controls, and equipment (such as using preheated air for jets) make hot tubs more energy-efficient than 5 or 10 years ago. When possible replace your hot tub with a newer energy efficient model. An average sized energy efficient hot tub consumes 5-7 kWh per day, while a poorly insulated, inefficient hot tub may use 12-18 kWh per day.
Ways to save energy and water with your swimming pool
Use a cover. Covers reduce temperature loss during non-use times. They keep the pool cleaner and cut back on water lost from evaporation. Solar covers can add up to 10ºF. taking some of the load off conventional heaters. If the solar cover is put on a month early, the sun alone may heat the water 20ºF. You may want to consider a cover with a reel system. It makes it easier and more convenient to take the cover off and on - prolonging the life of the cover and saving energy.
Add a "chemical cover." Chemical covers produce a micro thin layer on the water's surface - reducing heat loss and saving energy.
Add a safety cover. Safety covers reduce energy costs and add a protection barrier for small children, non-swimmers, pets, or uninvited guests.
Set pool temperature to 78ºF. The Red Cross recommends 78ºF. for swimmers. Each rise of one degree significantly increases energy costs. If you want higher temperatures, then consider alternative forms of heat such as solar covers and solar systems. Service your heaters annually to ensure they function at top efficiency. Or, replace older heaters with newer more energy efficient units.
Follow the recommended circulation times. Circulation times can vary - follow your manufacturer or builder's recommendations. The basic rule for a residential pool is to circulate water as needed. Eight hours a day may be enough - adjusting circulation up or down as necessary - to keep the water clean, clear, and safe. Clean filters only when necessary. For sand filters make sure the sand bed is fresh to lengthen the time between backwashing. By changing the sand or at least running a chemical cleaner through the sand you also help reduce the need to backwash. If you backwash sand filters too early, you waste both water and power, and reduce efficient operation. For cartridge filters be sure to size the filters properly - you'll save time and money by lengthening the time between cleanings. Watch your pressure gauges and look for an 8–10 psi increase before cleaning.
Install energy efficient motors or a smaller pump or motor.
Add a time clock. Use a programmable timer to automatically regulate the hours of operation. You can limit the total number of hours that the pump will operate and you can also set it to run during off-peak hours 10 a.m. to 5 p.m. and 9 p.m. to 6 a.m.
Correct any leaks or service problems as they occur. Do not allow problems with your pool to linger.
Inspect automatic pool cleaners to make sure they are in peak operating condition. Use automatic pool cleaners to maintain the cleanliness of your pool, but not for major clean-ups. Leaf rakes and leaf eaters do a better job of removing large loads then any automatic cleaner. Consider changing to a cleaner that can operate separately from the rest of the system.
Have users keep the water in the pool. Encourage games that focus on keeping the water in the pool. Jumping, splashing, and water fights consume water that has been heated and chemically treated.
Drain pools - rarely. Properly maintain your pool to maximize the useful life of the water. Consider alternative forms of care to help keep the water fresh and reduce time spent on pool maintenance. Pools seldom require draining. Consult a professional before draining your pool.
Create windbreaks around the pool. Cutting wind exposure can reduce loss of both heat and water. Privacy panels, landscaping, or fencing can all be effective windbreaks.
Call on your professional pool and spa dealers to help you make informed choices on all aspects of your pool or spa operation.
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Hot Tub and Pool Conservation Tips