3-Star vs 5-Star AC Calculator
Compare the running costs of two AC models and estimate whether energy savings recover the extra purchase cost. Use average wall power for your schedule or matching annual energy-label figures.
Inputs
Compare similar cooling capacities and matching label periods. Star counts do not imply a fixed saving percentage.
Use the selected currency. Enter the price difference, not the full purchase price.
For seasonal use, count only days the appliance runs.
AC savings & payback
Estimated yearly saving
360 kWh less per year (22.7%)| Period | 3-star AC | 5-star AC |
|---|---|---|
| Usage day | ₹70.408.8 kWh | ₹54.406.8 kWh |
| Month (30 days) | ₹2,112.00264 kWh | ₹1,632.00204 kWh |
| Year (180 days) | ₹12,672.001,584 kWh | ₹9,792.001,224 kWh |
- Extra upfront cost
- ₹10,000.00
- Simple payback
- 3.5 years
Savings use your entered power or label data. Payback excludes maintenance, financing, future tariff changes and equipment life.
Power mode uses the same operating hours and seasonal days for both ACs. Use session-average power, not maximum rated wattage.
How this calculator works
Compare like with like
Use models with comparable cooling capacity, and compare labels issued under the same test and rating period. BEE’s ISEER reflects seasonal test performance; star counts alone are not an electrical wattage measurement or a fixed percentage saving.
Choose power or label comparison
Power mode applies one operating schedule to both average input powers. Label mode uses each entered annual kWh without scaling it to an invented operating schedule. Its daily values divide annual label energy by 365; monthly values are averages of those label-test figures.
Calculate simple payback
Divide the extra purchase price by positive annual running-cost savings. A zero electricity rate, zero annual usage or an equally costly replacement produces no energy-cost payback. If the replacement uses more electricity, the tool shows an extra cost rather than claiming savings.
Calculation formulas
Annual kWh (power mode) = Average input W ÷ 1,000 × Hours/day × Usage days/yearAnnual saving = (3-star annual kWh − 5-star annual kWh) × RateSimple payback years = Extra upfront cost ÷ Positive annual cost savingWorked example
Illustration: average inputs of 1,100 W and 850 W, each running 8 hours on 180 days per year, differ by 360 kWh/year. At an example ₹8/kWh, the saving is ₹2,880/year. An extra purchase cost of ₹10,000 has a simple payback of about 3.47 years. These watts are examples, not generic ratings for all 3-star and 5-star ACs.
Understanding the estimate
All prefilled powers, usage patterns and rates are editable examples. This tool runs locally in your browser. Energy-only estimates are not complete electricity bills, and comparisons are scenarios rather than guaranteed savings.
Frequently asked questions
Does a 5-star AC always save a fixed percentage?
No. Savings depend on the specific models, their capacity, label period, usage and actual operating conditions. Enter measured average watts or matching annual label kWh instead of assuming a fixed percentage.
Can I enter ISEER as annual kWh?
No. ISEER is an efficiency ratio, not yearly electricity units. Use annual energy consumption from comparable labels, or average electrical input watts.
Is simple payback the full ownership cost?
No. It excludes financing, maintenance, resale value, equipment life and changing electricity rates. Use it as one input to a purchase decision, not a guarantee.