Question 1

What is a 'unit' of electricity?

Accepted Answer

One unit of electricity equals one kilowatt-hour (kWh) — the energy a 1,000-watt device consumes in one hour. Your electricity bill is charged in units (kWh). A 100W bulb running for 10 hours uses 1 kWh = 1 unit. Enter your tariff as ₹ per kWh.

Question 2

Why does the annual figure not equal monthly × 12?

Accepted Answer

The annual consumption is daily kWh × 365 — not monthly kWh × 12. At 30 days per month, monthly × 12 gives 360 days, which is 5 days short of a full year. The calculator uses 365 to give the correct full-year figure. At ₹8/unit and 12 kWh/day the gap is 5 × 12 × ₹8 = ₹480 — meaningful for high-wattage appliances.

Question 3

Where do I find my appliance's wattage?

Accepted Answer

On the appliance label, product manual, or BEE/ISI rating sticker — usually marked in watts (W) or kilowatts (kW). If it shows kW, multiply by 1,000 to get watts: a 1.5 kW air conditioner is 1,500 W.

Question 4

What if I enter 0 hours per day?

Accepted Answer

Zero is a valid hours-per-day value — it means the device is plugged in but not in active use. The result is zero consumption and zero cost.

Question 5

My electricity rate varies by slab — which rate should I use?

Accepted Answer

Use an effective average rate: divide your total electricity bill for a recent month by the units consumed that month. This single number reflects your blended cost across all slabs. The calculator applies a flat rate — it does not model progressive tariff tiers.

Question 6

Why is there a 'days per month' input?

Accepted Answer

Some appliances are seasonal — an air conditioner might run for 25 days in a month, not 30. Adjusting days-per-month gives a more accurate monthly cost for intermittent use. The annual figure always uses 365 days regardless of this setting.

Power Consumption Calculator

How power consumption is calculated

Example — 1,500W AC, 8 h/day, ₹8 per Unit

Annual cost uses 365 days — not monthly × 12

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