DSL GAM ENTERPRISES
ROI CALCULATOR

This calculator will determine the annual energy cost savings and life-time energy cost savings when you upgrade bulbs to a newer LED type bulb. You can also calculate the savings in the reduction in bulb changes due to the longer bulb life. You can use this sheet for each bulb type upgraded. It requires the wattage and bulb life for both the old and new bulb and the local cost per kilowatt-hour. This averages Php 15 in Manila. Additionally the cost to change a single light bulb and the cost of the initial install of the LED light bulb. You may want to include all of the costs of changing bulbs such as labor, inventory, warehousing and purchasing/accounting.

Simply fill in the shaded cells.

 
1. Compute the total power (kilowatts, kW) saved by upgrading older Bulbs to energy saving LED replacements
Original
Bulb Wattage		   Replacement
Bulb Wattage		   Watts Saved
per Bulb		   # of Bulbs
to Replace		   Total Watts
Saved		 Total Kilowatts
Saved
W   -  W   =  W   X  Bulbs   Label W / 1000 Label  kW
                   
2. Compute the total energy (kilowatt hours, kWh) saved annually by performing this upgrade
Total Kilowatts
Saved		   Hours of Use
per Day		   Days of Use
per Week		   Week of Use
per Year		   Total kWh
Saved per Year		  
Label kW   X  hrs/day  X   day/week X  wks/yr = Label kWh/yr  
                   
3. Compute the total energy cost savings per year
Total kWh
Saved per Year		   Your Energy Cost
per kWh (typically Php 15)		   Total Energy Cost
Savings per Year		          
Label kWh/yr  X  Php  =  PhpLabel           
                   
4. Compute the lifetime energy cost savings 
Replacement
Bulb Life (hours)		   Hours per Year
Usage		   Your Energy Cost
per kWh (typically Php 15)		   Lifetime Energy
Cost Savings		      
 Hr  /  Label hr/yr  X   PhpLabel  =  PhpLabel      
                   
Simple Payback on = Initial Cost of LED Light Bulb = Php  X Label Bulbs = Label years   
Energy Consumption   Total Energy Cost Savings per Year   PhpLabel      
                   
Return on Investment = 100     = 100 = Label%   
(ROI)   Simple Payback       Label       
                   
5. Compute the lifetime labor/inventory/acquisition costs savings from upgrading to longer life LED replacements
Replacement
Bulb Life (hours)		   Original
Bulb Life (hours)		   Labor Cost to
Change Original Bulb		   Cost of
Original Bulb		   # of Bulbs
to Replace		   Cost to Install
Replacement LED Bulb		   Total Lifetime Bulb
Changing Cost Savings
Label Hr  /  Hr  X (Php + Php ) X Label Bulbs  - Php = PhpLabel
                   
6. Compute the amortized bulb changing cost savings per year
Total Lifetime Replacement Cost Savings Total Lifetime of Replacement Bulb Total Amortized Replacement
Cost Savings per Year
PhpLabel / Label years  = PhpLabel  
                   
Simple Payback on = Initial Cost of Lighting Upgrade = Label = Label Years
Energy Consumption
Plus Replacement Costs		 Total Energy + Replacement Cost
Savings per year		 Label
                   
Return on Investment = 100 = 100 = Label%
(ROI) Simple Payback Label