/</IT 

US. Department of Energy June 1999 

Clothes Washer Life Cycle Cost (LCC) 

Spreadsheet Instructions 

What does the Life-Cycle Cost (LCC) spreadsheet do? 

The LCC spreadsheet (currently LccCW _ 7 .xis) performs calculations for life-cycle cost and 

payback periods. The LCC spreadsheet operates in Excel 97 or Excel 7 (Windows 95). The 

Excel add-on Crystal Ball (version 4.0) allows the user to perform uncertainty analysis on key 

input variables. 

What are the Worksheets in the Workbook? 

The workbook LccCW _7.xls includes the following worksheets: 

LCC (Sample Cale) 

LCC (Distributions) 

Water JPrice Dist 

Household Data 

Engineering 

Energy Price 

drate dist 

Lifetime 

contains the input selections and a summary table of energy use, 

operating costs, LCC and Payback. 

contains the input selections as in the LCC (Sample Cale) sheet. 

The energy, cost, LCC and payback data are for the current sample 

if Crystal Ball is running or the last sample run if not currently 

running. 

contains price and escalation data for water. 

contains marginal energy prices for each sample household, washer 

cycles per year for each household, and fuel use distributions. 

contains the manufacturer costs for each efficiency level, as well as 

the manufacturer and retail markups. 

contains energy prices from the various sources of energy price 

information; this is used for determining the energy price escalation. 

contains data from which an average discount rate and a 

distribution of discount rates is determined. 

contains the retirement function for clothes washers and the 

average clothes washer lifetime in years. 

1 
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 Cale) or LCC (Distributions). 

2. Use Excel's commands at the top View/Zoom to change the size of the display to make it 

fit your monitor. Note, that the zoom level for each of the worksheets should be set to the 

--same value. Otherwise a bug in Excel will cause a 'Not enough system resources to 

display completely' error. 

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 on either of two work sheets: 

a) LCC (Sample Cale) or, 

b) LCC (Distributions). 

A change in either input sheet also changes the other. In the box titled List Inputs select 

choices from the selection boxes for (1) energy price projectio~ (2) start year, (3) baseline 

design, (4) standard case design, (5) water heater (WH) I dryer combination, (6) water 

escalation rate, (7) manufacturer's cost (percentile or distribution). 

On the LCC (Distributions) worksheet, discount rate can also be entered if a value other 

than the default distribution is wanted. After any changes, restore this value to 

=drate _dist if you wish to restore the default distributions. 

On the LCC (Sample Cale) worksheet, non-default values can be specified for the discount 

rate, clothes washer lifetime, cycles (wash loads) per year and energy prices. Click on the 

Restore Defaults command button if you want to restore the default values for these 

parameters in this worksheet. 

4. To change assumptions on List Inputs click on the assumption you wish to change, and 

click on the new assumption from the menu. 

2 
5. This spreadsheet gives the user two methods of running the spreadsheet. 

a) If the LCC (Sample Cale) 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 new values are entered. 

b) Alternately, if the LCC (distributions) sheet is used. The spreadsheet generates results 

that are distributions. Some of the inputs are also distributions. The results on the LCC 

distribution that are shown as single values only refer to the results from the 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 Calculation) sheet used for? 

LCC difference and Payback are in the LCC (Sample Cale) sheet are based on single point values. 

This page can be used to see the effect of changing a single parameter. It is also used to 

determine a rebuttable presumption payback (when inputs are based on test procedure values 

wherever possible). 

How does the user run the Crystal Ball simulation? (LCC Distribution 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 the Run menu. After each simulation run, the user needs to 

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 obtain further statistical information. The time taken to 

i::omplete a run sequence can be reduced by minimizing the CrystaI Ball window in Excel. 

A step by step swnmary of the procedure, for running a distribution analysis, is outlined below: 

1. Find the Crystal Ball toolbar 

2. Click on RUN 

3. Select Preference and choose from the following choices: 

a) Monte Carlo 1 

b) Latin Hypercube 

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

1

Because of the nature of the program, there is some variation in results due to random sampling when 

Monte Carlo or Latin Hypercube sampling is used. 

3 
d) Select number of Monte Carlo Trials (we suggest 10,000 for high accuracy 

calculations and 500 for quick calculations). 

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

RUN 

RESET 

RUN 

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 Monte Carlo run, to see the distribution charts generated, 

--Click on the Windows tab bar that is labeled Crystal Ball. 

2. Currently, 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 bring it into view. The charts show the low and high endpoints 

of the forecasts. The View selection on the CB toolbar can be used to specify whether 

you want cumulative or frequency plots shown. 

3. To calculate the probability ofLCC savings being positive, 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 the likelihood that the LCC difference between the baseline and 

standard case will be positive. To calculate the 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 information on Crystal Ball outputs, please refer to 

Understanding the Forecast Chart in the Crystal Ball manual. 

4