Maximum Benefit, Minimum Energy Cost

Posted by on Oct 25, 2010 in Blog | Comments Off

Although few people who have experienced using a hot tub dispute its magical massaging powers, some consumers worry about operating costs. But fear not, portable hot tubs use less electricity than one might expect, and they have minimal effect on residential energy consumption. Consumers can save even more by upgrading to a newer, more efficient hot tub and by following a few basic energy conservation suggestions.

Concerned about energy-use perceptions, industry experts and some manufacturers have hired independent laboratories to investi-gate hot tub energy consumption. A West Coast power crisis prompted the National Spa and Pool Institute to hire the management consulting firm of Arthur D. Little, Boston, MA, to study the effect that self-contained electrical spas had on residential energy use. Little found that portable hot tubs account for less than 1 percent of the energy consumed in residential homes, and they contribute less than 0.3 percent to peak energy demand. The researchers based their calculations on the spa owner using the hot tub 16.4 times monthly for 20 minutes.

According to the study, at 10 cents per kilowatt, a typical portable hot tub costs about $22 per month to operate. At seven cents per kilowatt, the national average, this drops to $15 monthly, which means that a water heater or a color television set costs more to operate than a hot tub.

The Washington State University Cooperative Extension Energy Program estimates that an average-sized, energy-efficient hot tub consumes five to seven kilowatts daily. An older, poorly insulated spa could use up to 18 kilowatts per day. How much money this equates to will vary since electricity costs differ regionally. In addition, climactic disparities affect how long the hot tub heater must run to maintain the optimal temperature.

Manufacturers’ Testing

Tests results from independent testing companies have been reported by ThermoSpas, Inc., Wallingford, CT; Watkins Manufacturing, makers of Hot Spring® spas, Vista, CA; and Sundance ® Spas, Chino, CA.

In each test the water was at 102 degrees, and the air was at 70 degrees. However, since there were variables in the studiesdifferent costs per kilowatt, a 115-volt spa in one, a 120-volt spa in another, 20 minutes of running time in one, 30 minutes in anotherthe results of the studies are not comparable.

Still, the cost data is revealing, showing a range of 39 cents to 59 cents per day, amounts that would be considered negligible by virtually all middle-income families that might consider the purchase of a hot tub.

The Insulation Factor

The insulation in every hot tub is obviously important to block out the cold and to trap the heat generated by spa motors. Insulation materials and techniques vary, some companies using a full-foam approach and others using a layered approach, as well as variations of each. All major spa manufacturers take pride in their particular applications, but you may want to ask about the details for any model under serious consideration. The answer is likely to give you a feeling of comfort in every sense of the word.

Conserving Energy with an Existing Spa

Homeowners already enjoying a spa’s relaxing benefits can decrease energy consumption by following a few simple recommendations.

  • Always close and secure a snug-fitting, foam-insulating cover. Replace the cover if the interior foam becomes water logged or broken. Consider adding a floating thermal blanket to retain heat and to prevent moisture from building up inside the cover.
  • Ask about the covers R-value, a measure of insulation power. Standard covers typically have an R-12 insulating value, but some manufacturers, including Marquis Spas ® and ThermoSpas, Inc., add higher-density material to beef up the insulating ability.
  • Set the temperature at 102 degrees or lower. Setting the temperature higher will increase your operating cost unnecessarily.
  • If the hot tub has a timer, shift heating to off-peak hours, 6 A.M. to 10 A.M. and 5 P.M. to 9 P.M.
  • When away for a week or longer, turn the thermostat down. It will cost a few dollars to reheat the water, but the longer you are away, the more you can save.
  • To avoid wasting water, repair any leaks and drain the hot tub only as needed; draining often depends on the frequency of use, but it is typically every three to six months.
  • Shelter the hot tub with privacy panels, fencing or shrubs to block the wind. This could lessen energy consumption by as much as 5 percent.
  • Installing the hot tub in a sunny spot can decrease electrical use by an additional 5 percent.
  • Keep the hot tub in good working condition, following the manufacturer’s maintenance recommendations.

Study after independent study shows that today’s energy-efficient hot tubs cost little to operate, while providing priceless opportunities for relaxation, hydrotherapy, conversation and sheer pleasure.