A 3-ton central air conditioner in Florida costs about $124.17 in July and $814 a year at 15.32¢/kWh; an 8,000 BTU window unit about $25.91 in July.
At 15.32¢/kWh — Florida average, Jan–Aug 2026 (EIA). That is 16% below the U.S. average of 18.19¢.
| Efficiency | Per year | vs yours |
|---|---|---|
| SEER2 13.4 (min · North) | $868 | +$54.66 |
| SEER2 14.3 (min · South) | $814 | — |
| SEER2 15.2 (ENERGY STAR) | $766 | −$48.18 |
| SEER2 17 (ES average) | $685 | −$129 |
| Month | Full-load hours | 3-ton central | 8,000 BTU window |
|---|---|---|---|
| January | 60 | $23.07 | $4.81 |
| February | 56 | $21.41 | $4.47 |
| March | 87 | $33.54 | $7.00 |
| April | 122 | $46.86 | $9.78 |
| May | 217 | $83.73 | $17.47 |
| June | 284 | $109.66 | $22.88 |
| July | 322 | $124.17 | $25.91 |
| August | 321 | $123.93 | $25.86 |
| September | 282 | $108.95 | $22.73 |
| October | 191 | $73.50 | $15.34 |
| November | 105 | $40.68 | $8.49 |
| December | 63 | $24.26 | $5.06 |
DOE's room-AC test assumes 750 full-load hours a year for a typical U.S. home. We scale it by Florida's population-weighted cooling degree days (3,421 ÷ 1,216) and spread it over the months the same way: 2,110 hours a year. Your thermostat setting and insulation move this a lot — switch the calculator to your own hours if you know them.
3 tons = 36,000 BTU/h ÷ SEER2 14.3 = 2,517 W. × 2,110 h = 5,312 kWh × 15.32¢ = $814.
The full method, material data and tips are on the main air conditioner cost calculator page.