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Lighting ROI Calculator



Find Payback
in costs & maint.
with LED Lighting


Please read: This calculator gives payback time, and both the annual and life-time cost & savings figures for energy and maintenance.  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.
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ENSURE THAT LIGHTING REPLACEMENT HAS EQUIVALENT PERFORMANCE
Go to Graphics Version
      Comparisons        Compare CO2        Show LPD        Cookies
 Select Enter Power Factor (PF) 95 for residential.
Fuel:  Coal   Petroleum
Natural Gas   Hydro   Nuclear
CO2 Reduction from original by lower power consumption.

 Metric Tons Less / year
 Metric Tons Less / lifetime
Simple Comparisons
(Not photometric)

Original
Restore
Defaults

LED
  Cookie Jar  
 
   

Parameters for Calculations:  
 Enter:  Power (W),  Power Factor (PF),  Quantity & Time On
Original W  & PF % LED W Quantity 
 Totals:          Electricity $/kWh
Time On:  Hours/Day  ×   Days/Wk  ×   Weeks/Yr 
Annual Energy Cost: Original
$
LED
$
 
Basic Energy 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

Results:  Payback time, ROI, Equipment 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 year =  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 values provided by the US EPA.
Home         ©2011-2015 Patrick Mullins     Please Contact me with any comments regarding this calculator.