How Much Electricity Does an Air Cooler Use?

Electricity is billed in units. A unit is a kilowatt drawn for an hour. So the whole calculation is: watts × hours per day × days ÷ 1,000 × tariff.

A 190 W cooler running ten hours a day for a 180-day season uses 342 units, which at ₹8 a unit is ₹2,736. A 90 W personal cooler on the same schedule is 162 units, or ₹1,296. A 250 W desert cooler is 450 units, or ₹3,600.

Water is the other running cost and it is small. A mid-size desert cooler evaporates roughly 2-4 litres an hour in dry heat, so a ten-hour day is 20-40 litres — a fraction of what a washing machine uses.

A 20 litre personal cooler drawing 90 W is not more efficient than a 90 litre desert cooler drawing 220 W — it is simply smaller. Comparing their wattages directly would rank every small cooler above every large one, which tells a buyer nothing useful.

So the running-cost sub-score on every cooler here is computed as watts per litre of tank capacity where both are published. Below about 1.8 W per litre is genuinely efficient for the size; above about 4 W per litre is poor.

India published its first star-labelling programme for evaporative coolers in May 2025, voluntary from July 2025, with a mandatory phase from July 2026. So air-cooler star ratings are real, and over the next year or two they should become the easy comparison the category has never had.

For now, almost none of the manufacturer listings we read state a grade, which is why no cooler on this site carries a star figure. We compare rated input power instead. If you are standing in a shop and the box carries a BEE label, use it — it is better data than anything published online today.