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Lighting ROI Calculator



Find Payback
from costs & interest
with LED Lighting


Please read: This calculator gives payback time, and both the annual and life-time cost & savings figures for energy, maintenance, and CO2 production.  Graphics quickly illustrate financial and CO2 relationships which may apply to Carbon Credits and LEED.
          Click here to learn about Carbon Credits?
  Cookie Jar          
   Select Enter Power Factor (PF) 95 for residential.  
    Compare values during this  year LED life.   (Graphics are scaled to fit.)
LED 
Other 
Savings 
Return 
LED 
Other 
CO2 from  Coal    Petroleum    Natural Gas    Hydro Electric    Nuclear  *power generation.
Simple Comparison Options
(Not photometric)         

Original
Restore
Defaults

LED
  Cookie Jar  



LPD (Lighting Power Density)
 SqFt / Fixture =  Total
Target LPD =  fixtures  
LPD Statistics      W/SqFt
Original LPD      
new  LED LPD      
=  Saved      
See Table 1 Here
Parameters for energy statistics:  
Enter: Power (W), Power Factor (PF)%, Quantity & Time On
Original W  & PF LED  Quantity 
   Totals:        Energy $/kWh
Time OnHours/Day  ×  Days/Wk  ×  Weeks/Yr 
Annual Energy Cost: Original
$
LED
$
 
Savings:    Annual = $     Monthly = $      %
Results:
Annual Savings: $
()
Investment ÷ (Energy + Maint. Savings)
$ ÷ $ =  Year Payback 
(saved energy & maint. −Investment)
Investment
= Simple ROI %
Annual ROI:  
LED Investment:
 LED Life  Hours ÷   Hours/Year  =  Years Lifetime 
       Saves $ Energy
 Full Installed Cost Discounts for  1 Fixture = $  Interest 
 LED Maintenance Interval:  Years @ $  per Visit. 
     [Lifetime ÷ Interval × Cost × Quan.] = $
 ($ × ) + $ = $  + FIXED JOB COSTS $
         = $ Investment
  Subtract a rebate from FIXED JOB COSTS, or,
       enter negative (-)JOB COSTS if rebate only. 
Original fixture with lifetime maintenance and energy costs:
 $ One Fixture Installed
 Lamp life  Hours ÷  Hrs use per Yr =  Years Lifetime 
 LED Project Years × $ original annual energy = $
 Relamp = $(relamping, disposal, cleaning, etc. every  years)
 Original Cost with repair  times during LED Lifetime:
 $ + $ energy = $
 
green econometrics about CO2   *US national average CO2 emissions caused by various power fuels provided by the US EPA.
Home             ©2011-2015 Patrick Mullins     Please Contact me with any comments regarding this calculator.