Calculate the Impact of Use of an Appliance or Device on your Monthly Electric Bill
with Kill-A-Watt® Electricity Monitors
There are three types of usage you can monitor.
- To monitor a device that runs all the time, such as a refrigerator, cordless telephone or “phantom load”—the power used by certain devices even when they’re not being used—leave it plugged in for an hour.
- To monitor a device you use only for a few hours each day, such as a lamp or space heater, plug it into the Kill-A-Watt just before turning it on, and leave it plugged in for an hour. Keep track of how many hours per day you use the item.
- To monitor a device you use only once or twice each day, such as a coffee maker, hair dryer or toaster, plug it into the Kill-A-Watt, turn the appliance on, and read out the kilowatt hours after the appliance shuts off.
The formula for calculating the cost of an appliance or device for a month is:
[kilowatt readout] x[frequency of use] x30 (days in a month) x17¢ (the average cost of a kilowatt in Maine)
[.3 kWh (1 hour readout)]x[24 hours per day]x[30 days]x[17¢] = $36.72 per month
a 1,300-watt microwave oven used 3 minutes 5 times a day
[.065 kWh (one use readout)]x[5 uses per day]x[30 days]x[17¢] = $1.66 per month
Program Information: http://www.efficiencymaine.com/residential_programs.htm
Calculator and Examples derived from: Efficiency Maine Kill-A-Watt® Energy Detector Complete Instructions