The back or bottom of most household appliances has a wattage label.The maximum power the appliance can draw is listed on the label.To calculate total energy use, you need to convert this to kilowatt hours.
Step 1: The appliance label has the wattage on it.
There is an energy label on the back of most high-power appliances.The wattage is usually the maximum power the device operates at, which may be much higher than the average.The steps below will give you a rough estimate of kWh, but your actual usage is usually lower."200–300W" is a range of watt that some devices show.It is possible to choose the middle of the range, or 250W in this example.
Step 2: Wattage by hours is used each day.
Watts are used to measure power.Multiplying by a unit of time gives you an answer in terms of energy, which is what matters for your electrical bill.A 250 watt window fan can run for 5 hours a day.The fan's watt-hours are equal to the number of hours per day.Each season calculations are made for air conditioning and heating units.If you don't plug them in, they draw power for about 8 hours a day.
Step 3: The result should be divided by 1,000.
This step converts your answer from watt hours to kilowatt hours.1250 watt hours of energy per day is how much your fan uses.1000 watt hours is equivalent to 1 kilowatt.
Step 4: Measure the number of days you're measuring.
The device uses kilowatt-hours every day.You can use the number of days in a period to calculate your kWH.Over the course of 30 days, your fan would use.If you fan runs every day for a year, it would use.
Step 5: The cost of electricity is divided by the number of kWh.
The cost per kilowatt hour is listed on your electricity bill.You can find the amount you can expect to pay by taking this number and adding it to the kWh.If energy costs 17 cents/kWh, the cost of running the fan will be rounded to the nearest cent.The maximum estimates are based on the listed wattage.You would be charged less than this.You can find the cost of electricity in different areas if you search online.Start with the EIA website for US locations.
Step 6: You can find the rating on the appliance.
Some appliance labels don't list watt amounts.If this is the case, look for an Amp or "A" measurement.There are two Amp values listed on the laptop and phone chargers.You can use the one labeled input.
Step 7: You can find the voltage in your area.
The standard household voltage in the United States is 120V.The voltage in the EU and most of the world is between 220 and 240V.In the US, washing machines can be plugged into special circuits.The appliance label has a voltage rating.You can assume a professionally installed appliance matches the recommendation if you read the label.
Step 8: The two things are multiply and volts together.
The answer is in watt, or electrical power.A 120V outlet is plugged into a microwave label.It consumes a large amount of power.
Step 9: Use hours per day.
The appliance's wattage tells you how much energy is being used.Take the number of hours the device runs into account.If the microwave runs for half an hour each day, it would take 780 watt hours to run.
Step 10: You can divide by 1000.
The conversion is from watt hours to kilowatt hours.A kilowatt is 1000 watt hours.
Step 11: You can find kilowatt hours for a larger time period.
Divide your answer by 31 days to find out how many kilowatt hours you'll be charged for.x 31 days is 0.39 kilowatt hours.
Step 12: You can buy a power meter online.
This device is called a watt meter or kilowatt meter.This is usually more accurate than using the appliance's label info.If you're familiar with electrician's tools, you can use a multimeter.This requires access to the appliance's wiring.Unless you know what you're doing, don't disassemble anything.
Step 13: There is a meter between the outlet and the appliance.
The wall has a power meter.The appliance needs to be plugged into the power meter.
Step 14: The kilowatt hours are measured.
You can set the power meter to show kilowatt hours.The total kilowatt hours of the attached appliance should be calculated by the power meter if you keep it connected.If your power meter only measures watt, you can use the method above to calculate kilowatt hours.Refer to the power meter instructions if you don't know how to change it.
Step 15: The appliance should be used as usual.
The longer the power meter is plugged in, the more accurate it will be.
Step 16: You can find kilowatt hours.
From the time the device was plugged in, the kilowatt hours are displayed on the meter.You can use this number to estimate kWh over time.For example, if the meter has been running for 5 days, you want to find a 30-day estimate.The kWh displayed by 6 is 30 divided by 5.