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Residential Lighting

Economic Worksheet

Please use the following sheet to calculate annual energy savings, annual operating cost savings, and simple payback. Please note that some fields are defaulted to 1. These fields must contain a number, not zero, or the calculation will be inaccurate. Please refer to the Instructions for specific details and suggestions on how to enter appropriate data for each field.



Item Directions Design1 Design2 Units
A Enter lamp/ballast watts watts
B Enter number of lamps  
C Enter Power Reduction Factor  
D Enter the hours of one lamp's daily operation hours per day
E Enter motion detector factor  
Stop here if you only want to calculate annual energy savings - Click Calculate below.

F Enter cost of electricity dollars per kWh
G Enter average rated lamp life hours
H Enter lamp life multiplier  
I Enter price of one lamp dollars per lamp
Stop here if you are calculating annual operation cost savings - Click Calculate below.

J Enter the amount of incentive dollars
K Enter the price of lamp(s) [B x I] dollars
L Enter the price of ballast(s) dollars
M Enter the price of luminaire(s) dollars
N Enter the price of control(s) dollars
O Enter the total cost of labor dollars



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