Hot Tubs and Pools


Maximize the enjoyment you get from your hot tub or pool by ensuring its running at peak efficiency. Proper operation and maintenance of your heating and filtering equipment—or investing in newer, more energy-efficient models—can help reduce power consumption and increase savings.

Types of Hot Tubs and Pools

Pool Covers

Pool covers save money in a few ways.

• An uncovered heated pool is an enormous energy waster and can easily be costing more than it does to heat an entire home.
• Covers reduce evaporation, which robs heat, chemicals and water from the pool.
• Reduced evaporation also diminishes algae formation, lowering water treatment chemical requirements.

Two popular types of pool covers are opaque and transparent. Both will almost eliminate evaporative heat losses, which is the number one way pools lose heat. They come in manual and auto-reel versions; the latter, while definitely more convenient, requires a more substantial initial investment.

Opaque covers are generally used on spas or hot tubs, but there are models created especially for pools. Opaque covers do not allow solar gain, which may be an advantage or disadvantage depending on where you live and how you use your pool.

Transparent covers allow for solar gain, but may not be as durable as opaque covers. Check with your local pool supply dealer to learn about the types of covers available and invest in the one that works best for your pool and your lifestyle.

Pool Pumps

Pool pumps can use a significant amount of energy. For example, a one horsepower pump running for 12 hours at $.12 per kWh costs about $1.44. This equates to almost $43 per month, given that the pump only runs for 12 hours per day. For energy savings, run pool pumps the minimum number of hours needed to keep the pool clean. Time clocks make it possible to limit the number of hours the pump operates and control which hours it is on. You can also check with your local pool supply dealer to see if there is a more energy-efficient model you can install.

Spas & Hot Tubs

Spas and hot tubs can use a tremendous amount of energy, the vast majority going to heating and filtering water. Three major factors affect these operating costs:

1. Weather
2. Spa Size
3. Operating Temperature

The most important factor contributing to spa heating costs is the difference between the beginning water temperature and the final temperature. The larger the difference, the higher the costs. For example, to heat your spa from 70°F to 100°F and maintain that temperature for one hour costs about $2.97 in electricity; add $.16 per hour for the pump motor and another $.08 per hour for the aerator. (All figures based on a 6′ x 6′ spa of 500 gallons with a 2-hp filter pump and a 1-hp aerator. Energy costs used are $.08 per kilowatt-hour and $.50 per therm.)

To reduce your spa’s operating costs, keep it covered with a tight-fitting insulated cover when not in use. When installing a spa, insulate it well around the sides and bottom.

Heat the spa only when you plan to use it, allowing time for warm-up, and keep its temperature at 102°F or lower. Check the accuracy of your spa’s thermostat. An inaccurate thermostat can cost you hundreds of dollars each year.

Filtering is another major cost of owning a spa. Average spas have 2-hp filter pumps which cost about $.16 an hour to operate. These simple steps can help reduce filtering costs.

• Reduce the number of hours you filter. The average spa requires one-half to one hour of filtering each day.
• Filter enough to maintain water clarity. If you have a pool maintenance service, be sure to check with them before reducing filtration hours.
• Have your filter pump operation checked yearly by a qualified pool maintenance company. A malfunctioning filter pump costs more to operate.
• When it’s not needed, switch off your aerator, the device that adds bubbles to the water jets. An average aerator is 1-hp and costs about $.08 an hour to use.

In some climates, a solar heating system is an alternative way to heat your spa. Spas require solar panels with at least two times the surface area of the spa. You should consider several factors before deciding on a solar heating system for your spa:

• The initial cost of a solar heating system is generally higher than for a conventional heater
• A back-up heating system is required
• Solar heating systems work only during daylight hours and will not heat the spa at night