How These Costs Are Computed
One formula, two official sources, no estimates of ours.
The formula
cost per year = (annual kWh) × (electricity rate in
¢/kWh) ÷ 100
Worked example
The Aeocky RHEA-RCS32(Y)-N4-3 is certified at 339 kWh/year. The US average residential rate is 18.34¢/kWh (June 2026).
339 × 18.34 ÷ 100 =
$62.17 per year ≈ $62
Where the numbers come from
- Annual kWh per model: EPA's ENERGY STAR certified-products open data (data.energystar.gov, dataset mgiu-hu4z). This is the standardized annual energy figure each model reports for certification under the federal Appendix X1 test — measured the same way for every model, which is what makes the comparison fair.
- Electricity rates: US Energy Information Administration, Electric Power Monthly, Table 5.6.A — average residential price by state, June 2026. National average: 18.34¢/kWh.
Honest limitations
- The certified kWh/year is a standardized test figure, not your meter reading. Run the unit more hours, in a damper basement, or on a higher fan speed and your real cost will be higher; run it less and it will be lower. The ranking between models, however, holds.
- State rates are statewide residential averages. Your utility's exact rate may differ; if you know it, the formula above works with your number directly.
- Yearly dollars are rounded to the nearest dollar on these pages; monthly figures keep cents.
- Data refresh: quarterly. Models rejected by our validation checks (implausible capacity or energy figures) are excluded rather than published; exclusions are logged, never guessed at.