You can conduct a Home Audit to estimate your energy use. The wattage of appliances (equipment) and the amount of operating time can vary greatly. The following information will show you how to determine where the energy dollars are going in your home.
Step 1
Since the cost of electricity is determined by the number of kilowatt-hours (KWH) used during a billing period, the first step is to determine your average cost per kilowatt-hour. The average cost per kilowatt-hour is computed this way: Average Cost per KWH = $ amount of bill ÷ Total KWH used.
Step 2
Since the wattage of an appliance (equipment) determines the electrical usage per hour, the second step is to determine the wattage. The wattage of an appliance is found on the serial plate. But it is possible that the electrical requirements will be expressed in volts and amperes, rather than watts. If so, multiply volts times amperes to obtain the wattage.
Step 3
Use the formula shown in this example to estimate usage and cost. A light uses 100 watts and is left on for 15 hours. Compute the cost as follows: KWH use = (100 watts x 15 hours) ÷ 1000 watts = 1.5 KWH.
Step 4
To find your daily cost for electricity, divide your bill by the number of days in the month.
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