A 1.5 ton 5-star inverter AC running 8 hours a day costs roughly ₹1,750/month at ₹7 per unit; a 3-ton US central system at SEER2 14.3 costs about $103/month at $0.17/kWh. Adjust everything below for your unit and tariff.
ISEER values follow BEE inverter-AC star bands — verify against the current BEE table for the model year you're buying.
| Power draw | — |
| Monthly energy | — |
| Cost per day | — |
| Season cost | — |
| CO₂ · season | — |
What the same tonnage costs to run at each real US market tier, using your hours and rate above. Whether the premium tier pays back depends on the installed-price difference in the quote in front of you — typically $1,500–$4,000 between builder grade and variable-speed.
| Tier | SEER2 | Monthly | Season | Season savings vs Good |
|---|
Tiers reflect the actual market: US — SEER2 14.3 federal-minimum single-stage, 17 mid two-stage, 21 premium variable-speed. India — current BEE inverter bands (verify against the latest BEE table). Running costs only; equipment and install prices vary too much by region to estimate honestly here.
Two inputs decide most of the bill — get these honest and the estimate is close:
The estimate assumes steady conditions. In practice a lower thermostat setpoint, weak insulation, leaky ducts, extreme heat and marginal (slab) tariffs all push it up. Use your actual compressor-active hours and your top slab rate for the closest match.
Yes, mostly at partial load: an inverter modulates its speed instead of cycling full-on/off, so it sips power in mild weather and over long runtimes. The savings are biggest with high daily usage. See inverter vs non-inverter.
Roughly 3–5% of cooling energy per °F (about 6–8% per °C). Running 24°C instead of 22°C, or 76°F instead of 72°F, is a real cut over a season — often more than switching star ratings.
US buyers compare SEER2; Indian buyers use the BEE star / ISEER band. This calculator switches with the US/India toggle in the header. The ratings guide explains how each maps to running cost.
Efficiency inputs use SEER2 (AHRI 210/240, DOE 10 CFR 430) and BEE ISEER — ANSI/AHRI 210/240, BEE Star Label. Carbon estimates use grid-average emission factors — the US figure (≈0.37 kg CO₂/kWh) from EPA eGRID and the India figure (≈0.71 kg CO₂/kWh) from the CEA CO₂ Baseline Database. See SEER vs SEER2 and our full methodology.