How much does the kettle, the heater or the old fridge in the garage really cost to run? Enter its watts, how long it is on, and the price per kWh from your bill.
Cost per year
$93.08
547.5 kWh a year at $0.17 per kWh
| Use | Energy a year | Cost a year |
|---|---|---|
| 0.5 h a day | 273.8 kWh | $46.54 |
| 1 h a day | 547.5 kWh | $93.08 |
| 2 h a day | 1,095 kWh | $186.15 |
| 4 h a day | 2,190 kWh | $372.30 |
| 8 h a day | 4,380 kWh | $744.60 |
| 24 h a day | 13,140 kWh | $2,233.80 |
Estimates from the figures you enter: not a bill, and not financial advice.
Find the wattage on the appliance's label or in its manual. If only the current is given, multiply the amps by your supply voltage: 3 A × 120 V = 360 W. Then estimate how long it runs each day and on how many days a year, and take the price per kWh from your electricity bill.
kWh a day = watts × hours a day ÷ 1,000
kWh a year = kWh a day × days used a year
Cost a year = kWh a year × price per kWh
These are the steps the U.S. Department of Energy's Energy Saver guide sets out. The appliance list starts you from the middle of a typical nameplate range. A nameplate gives the most an appliance can draw, and fridges, heaters and pumps switch on and off, so count only the hours they really run, or measure with a plug-in energy meter.
Bulbs, standby, units and batteries.
Yearly savings, payback time and the cost over a whole LED lifetime.
Add up what your devices draw while they wait, device by device.
kWh, Wh, MJ, Btu and therms, prices per unit, and the cost of any amount.
mAh to Wh, realistic phone charges, and the 100 Wh and 160 Wh flight limits.
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Try WebTraceCheckThe daily cost is for a day the appliance is used. The monthly figure spreads the yearly cost evenly over 12 months, so it already allows for the days it stays off.
The energy rate on your bill. Fixed daily or monthly charges are paid whatever you use, so leave them out when you compare appliances.
Only the standby part. The standby power calculator adds up what devices draw while they wait, which is small per device but runs every hour of the year.