Find the wattage on the appliance label or manual. High-wattage appliances used for long periods cost the most. Power prices change, so use your current rate. Estimate only.
The calculator converts the wattage to kilowatts, multiplies by the hours used to get the energy per day in kilowatt hours, then by the days per year and your power price. The result is the annual running cost, broken down to a cost per hour and per day. Comparing appliances this way shows which ones are quietly expensive and worth using less or replacing with an efficient model.
A 2,000 watt heater used 4 hours a day for 150 days uses 8 kWh a day, 1,200 kWh a year. At 28 cents a unit that is about $336 a year, or roughly 56 cents an hour, which adds up over a winter.
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