What do the Life-Cycle Cost (LCC) spreadsheets do?

The LCC spreadsheets perform calculations to determine life-cycle cost and payback periods. The LCC spreadsheets operate in Excel 97 or Excel 7 (Windows 95). The Excel add-on Crystal Ball (version 4.0) allows the user to p

What are the Worksheets in the Workbook?

Each LCC spreadsheet or workbook consists of the following worksheets:LCC (Sample Calc) contains the input selections and a summary table of energy use, operating costs, LCC and Payback.LCC (Simulations) contains the input selections as in the LCC (Sample Calc) sheet. If Crystal Ball is running, the energy, cost, LCC, and payback data are from the current sample. If Crystal Ball has finished runningEngineering contains the manufacturer costs submitted by ARI for split systems and single package systems at each efficiency level. Also included are the manufacturer, distributor, and dealer markups, the saleRECS HH Data for each sample household, contains average and marginal electricity prices, annual space-cooling energy consumption (and space-heating energy consumption for heat pumps), the geographic locatCOMM Data for each sample building, contains average and marginal electricity prices, and annual space-cooling energy consumption (and space-heating energy consumption for heat pumps).Energy Price contains projections of future energy prices from various sources.SEER Dist contains historical shipment-weighted efficiency data by year; this is used for determining the probable SEER of existing space-conditioning equipment based on age.Seasonal Allocation Factors contains seasonal (i.e., summer and non-summer) allocation factors of annual cooling (or heating) energy which indicate the fraction used by season. The seasonal allocation factors are based on the 

are used for determining the annual marginal electricity rate. Summer and non-summer allocation factors are multiplied by summer and non-summer marginal rates, respectively, and then summed 

drate dist contains data from which an average discount rate and a distribution of discount rates are determined.Lifetime contains the survival function for central air conditioners and heat pumps and the average central air conditioner and heat pump lifetime in years.Setup this is used as an interface between user inputs and the rest of the worksheets -- do not modify this sheet.

How does the user operate the spreadsheet?

To execute the spreadsheets fully you will need both Microsoft Excel and Crystal Ball software. Both applications are commercially available. Crystal ball is available at http://www.decisioneering.com.

1) Once you have downloaded the LCC file from the Web, open the file using Excel. At the bottom, click on the tab for sheet LCC (Sample Calc) or LCC (Simulations). 2) Use Excel’s commands at the top View/Zoom to change the size of the display to make it fit your monitor.3) The user interacts with the spreadsheet by clicking choices or entering data using the graphical interface that comes with the spreadsheet. Choices can be selected from the box labeled List Inputs o

a) LCC (Sample Calc) or,

b) LCC (Simulations).

A change in either input sheet also changes the other. In the box titled List Inputs select choices from the selection boxes for the following: (1) energy price projection, (2) start year, (3) base case (6) system type (split or single package). A new discount rate or lifetime can also be entered if a value other than the default value or default distribution is wanted, however, this would change the ccode is changed.

a) energy price projection,

b) start year,

c) base case design, 

d) standard case design, 

e) system type (split or single package) (this choice appears just outside of the List Inputs box),

f) price multipler (either ARI Mean manufacuturer cost multipliers or Reverse Engineering manufacturer cost multipliers),

g) markups (gives the user the option to input their own manufacturer, distributor, dealer, and builder markups and sales tax), and

h) price multiplier (gives the user the option to input their own manufacturer cost multiplier).

4) To change assumptions on List Inputs click on the assumption you wish to change, click on the new assumption from the menu. 5) This spreadsheet gives the user two methods of running the spreadsheet. 

a) If the LCC (Sample Calc) sheet is chosen, then all calculations are performed for single input values, usually an average. The new results are shown on the same sheet as soon as the ne
b) Alternately, if the LCC (Simulations) sheet is used, the spreadsheet generates results that are distributions. Some of the inputs are also distributions. The results from the LCC distributi

last Monte Carlo sample and are therefore not meaningful. To run the distribution version of the spreadsheet the Excel add-in software called Crystal Ball must be enabled.

What is the LCC (Sample Calc) sheet used for? 

LCC difference and Payback as provided in the LCC (Sample Calc) sheet are based on single-point values. This page can be used to see the effect of changing a single parameter. 

How does the user run the Crystal Ball simulation? (LCC Simulations sheet)

To produce sensitivity results using Crystal Ball, you need simply select Run from the Run menu (on the menu bar). To make basic changes in the run sequence, including altering the number of trials, select Run Preferences from select Reset (also from the Run menu) before Run can be selected again. Once Crystal Ball has completed its run sequence it will produce a series of distributions. Using the menu bars on the distribution results it is possible to oba run sequence can be reduced by minimizing the Crystal Ball window in Excel. A step by step summary of the procedure, for running a distribution analysis, is outlined below:

1) Find the Crystal Ball toolbar (at top of screen)2) Click on RUN3) Select Preference and choose from the following choices:

a) Monte Carlo

b) Latin Hypercube (recommended)

c) Initial seed choices and whether you want it to be constant between runs

d) Select number of Monte Carlo Trials (we suggest 10,000).

4) To run the simulation, follow the following sequence (on the Crystal Ball toolbar)

RUNRESETRUN

5) Now wait until the program informs you that the simulation is completed.

What kind of output does Crystal Ball generate?

1) After the simulation has finished, to see the distribution charts generated, click on the Windows tab bar that is labeled Crystal Ball.2) The life-cycle cost savings and payback periods are defined as Forecast cells. The frequency charts display the results of the simulations, or trials, performed by Crystal Ball. Click on any chart to b

of the forecasts. The View selection on the Crystal Ball toolbar can be used to specify whether you want cumulative or frequency plots shown.

3) To calculate the probability of that LCC savings will occur, either type 0 in the box by the right arrow, or move the arrow key with the cursor to 0 on the scale. The value in the Certainty box shows 

certainty of payback period being below a certain number of years, choose that value as the high endpoint.

4) To generate a printout report, select Create Report from the Run menu. The toolbar choice of Forecast Windows allows you to select the charts and statistics you are interested in. For further inform

the Forecast Chart in the Crystal Ball manual.