How to Calculate the Cost of Running an Appliance

Most appliances and other electrical equipment have a nameplate that indicates the power requirements.

To calculate the wattage for any appliance, use the formulas below: 

For single phase equipment (any residential equipment):
Watts = volts x amps

For three phase equipment (found in some commercial and most industrial equipment): 
Watts = volts x amps x 1.732 (1.732 is the square root of 3) 
  

To determine the cost of running an appliance, use these formulas: 
Wattage x Hours Used / 1000 = kWh 
kWh x cost of electricity = cost