Less Power = More Saving $$$
Pumps don't need to run at full power all the time to keep your pool water clean. Variable speed pool pumps are far more efficient compared to single-speed and two-speed pumps as they allow you to control the speed (RPM) of the pump, whether low or high or anywhere in between.
When you choose a variable-speed pool pump , you'll have a higher up-front cost, but bigger savings over time. Typically, pool owners who switch to variable-speed pumps recover the cost of the pump in energy savings in less than two years.
You could save up to 83 percent in annual energy costs (give or take, depending on where you live and other variables) just by upgrading your pool pump.
Source: Swim University