Variable-speed pump (VS pump)
Also called: VS pump, VSP, variable speed pool pump.
A variable-speed pump is a pool pump that can be programmed to run at different speeds, so it filters slowly for long hours instead of at one fixed speed. Flow falls in step with speed but power falls much faster, so a slow pump moves more water per kilowatt-hour.
Why it matters
The Florida Solar Energy Center metered five Florida homes that swapped a single-speed pump for a variable-speed one: savings averaged 68% and ranged from 49%–80%. Single-speed pumps are not banned, but since September 29, 2025 every new pool-pump motor from 1.15 to 5 total horsepower must be variable-speed, and motors from 0.5 to 1.15 follow on September 28, 2027. The saving lives in the schedule: a variable-speed pump left at a high speed all day is an expensive single-speed. On an above-ground pool the gain is small; ENERGY STAR puts a certified above-ground pump at 11% less energy than a new pump that only meets the federal minimum.
In numbers
In ENERGY STAR's test data a Pentair IntelliFlo VSF moves 77.5 GPM at 1,295 W and 31.2 GPM at 115 W, about 4.5 times the water per kilowatt-hour.