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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.  It calculates Lighting Power Density from area of at least 500 square feet per fixture, and provides the maximum fixtures allowed from a target LPD.  Check the DOE for your requirement.  Non-residential electric usually has additional cost if lower than 90% Power Factor.
          Calculator will not perform properly if removed from this site. 
   ENSURE THAT LIGHTING REPLACEMENT HAS EQUIVALENT PERFORMANCE.
 
        Comparisons        Compare CO2        Cookies
   
   Select Enter Power Factor (PF) 95 for residential.
Simple Comparison Options
(Not photometric)         

Original
Restore
Defaults

LED
 
  Cookie Jar  



Parameters for energy statistics:  
 Enter:  Power (W),  Power Factor (PF),  Quantity & Time On
Original W  & PF % LED  Quantity 
   Totals:        Electricity $/kWh
Time On:  Hours/Day  ×   Days/Wk  ×   Weeks/Yr 
Annual Energy Cost: Original
$
LED
$
 
Savings:    Annual = $     Monthly = $      %
LPD (Lighting Power Density)
 SqFt / Fixture =  Total
Target LPD =  fixtures  
LPD Statistics      W/SqFt
Original LPD      
new  LED LPD      
=  Saved      
See Table 1 Here
 
Fuel:  Coal   Petroleum
Natural Gas   Hydro   Nuclear
CO2 Reduction from original by
lower power consumption.
 Metric Tons Less / year
 Metric Tons Less / lifetime
Results:  Payback time, ROI, Savings, Cost & Interest
 Annual Savings:
             
  Investment ÷ (Energy + Maint. Savings)
                 $ ÷ $  =  Year Payback 
 Simple ROI(saved energy & maint. −Investment)÷Investment = % 
           Annual ROI:            LED to Original cost:  
   Payment Count Choice:  by savings, or,      by selection.
 (define Lease or Finance program)      $
 
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 = $
 
 *US national average CO2 emissions caused by various power generation capabilities, value provided by the US EPA. 
            Home             ©2011-2015 Patrick Mullins     Please Contact me with any comments regarding this calculator.