calcs.homes
calcs.homes
Enter your air conditioner's capacity, the old and new SEER ratings, your cooling hours, and your power rate to see how much a higher-SEER unit saves each year.
Estimate only — real savings depend on run time, humidity, thermostat habits, and install quality.
SEER is cooling output in BTU divided by electricity input in watt-hours over a season. Annual kWh is capacity ÷ SEER × cooling hours ÷ 1,000. We run that for the old and new ratings, take the difference for kWh saved, and multiply by your rate for the dollar figure. The 10-year number is a simple ten times the annual saving, ignoring rate inflation and equipment aging.
The efficiency gain is real but shrinks as SEER climbs — going from 10 to 14 saves far more than 16 to 20, because savings scale with the difference of the reciprocals. Weigh the annual saving against the price step between units, and remember a correct charge, sealed ducts, and right-sizing often matter more than the last few SEER points.
It cuts cooling energy about 12% versus 14 SEER. Whether that pays back depends on your cooling hours and power price — big in Arizona, marginal in Maine.
SEER2 is a newer test with a higher static pressure that better reflects real ducted systems. A SEER2 number is roughly 4–5% lower than the old SEER for the same equipment.
Not colder — it reaches the same setpoint using less electricity, often with variable-speed parts that also improve humidity control and quiet.