Follow this simple formula and calculate the cost of your pool pump or any household appliance.

watts/1000 = kW x hours of operation = kWh x kWh rate = cost

For example, look at the pool pump motor, towards the back and near the top there is a information plate and on the information plate there will be an item that looks like:  KW 1.55, this is the amount of kilowatts that motor will use in 1 hour.  To put it to use, take this number and include it in the formula. For example:

1.55 (killowatts) x 8 (hours the pump runs) = 12.4 x $.13 = $1.61 for one days use or x 30 for an average month $48.30.  The $.13 comes from published estimate from Florida Power and Light in central Florida, use your areas numbers for best results.

To put that number in perspective consider:

Grande Lotte at Starbucks      $3.55

Red Bull from Walgreens       $3.99

6 inch sub at Sub Way           $4.50

One days house usage          $3.23 (FPL estimates 2012)

If the only information you are getting is amps, then the formula changes to:

8 amps x 120 volts household current = 960 watts/1000 = .96 kW x 45 hours = 43.2 kWh x $.13 = 5.62

The time it takes to initially warm your pool or spa depends on several factors.

First, determine how many gallons of water are to be heated.  Knowing this, you can then compute the equivalent pound of water involved, and the BTU’s necessary to heat the volume of water to the desired temperature.

Note also that if you are trying to heat up an attached spa, only use the volume of the spa, as the whole pool and spa don’t need to be heated.  And then don’t forget to turn off the pool circulation, only using the spa.

Next find the approximate BTU output of your heater.  This can be found on the information plate on the heater or in your manual.  To be more accurate, determine the BTU output at the current temperature or expected temp at the time you want to use it if only heating the attached spa.  This will be harder to find but try the manufacture of your heater for specifics, they may have them on their web site.

Finally, decide at what temperature you plan to either maintain your pool at, or increase the temp to.

The following work sheet can be used to calculate approximate time required for your heater to bring the pool or spa to the desired temperature.  Keep in mind heating times will vary somewhat due to weather conditions and the use of a pool blanket can greatly reduce the time.