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APPENDIX 8A. USER INSTRUCTIONS FOR LIFE-CYCLE COST AND 

PAYBACK PERIOD SPREADSHEETS

TABLE OF CONTENTS

8A.1 DEFINITIONS........................................................................................................ 8A-1

8A.2 BASIC INSTRUCTIONS....................................................................................... 8A-3
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APPENDIX 8A. USER INSTRUCTIONS FOR LIFE-CYCLE COST AND PAYBACK 

PERIOD SPREADSHEETS

8A.1 DEFINITIONS

The interested reader can examine and reproduce detailed results of the U.S. Department 

of Energy’s (DOE’s) life-cycle cost (LCC) and payback period (PBP) analysis for residential 

dishwashers by using Microsoft Excel spreadsheets available on DOE’s website at 

http://www1.eere.energy.gov/buildings/appliance_standards/residential/dishwashers.html. 

To fully execute the spreadsheets requires both Microsoft Excel and Crystal Ball software. Both 

applications are commercially available. Crystal Ball is available at www.decisioneering.com. 

The latest version of the workbook, which is posted on the DOE website, was tested 

using Microsoft Excel 2007. The LCC and PBP workbook for residential dishwashers comprises 

the following worksheets.

Statistics Presents a statistical summary of the simulation runs performed: 

the range in LCC savings and PBPs; retail purchase price; total 

installed cost; total operating costs over the product lifetime 

(discounted); annual electricity, gas, and oil use; annual water use;

and household characteristics. The worksheet provides minimum, 

maximum, and average values, along with 5th, 25th, 50th, 75th, and 

95th percentile values.

Summary Presents the results of an analysis in terms of average LCC, LCC

savings, and median, average, and undefined PBP for both 

standard-sized and compact dishwashers. A table includes, for each 

efficiency level considered, installed price; lifetime operating cost;

LCC; average savings; and the percentage of households that 

would incur a net cost, no impact, or net savings from each 

standard level. The user can stipulate three parameters for a 

simulation run: whether the AEO energy price trend reflects an 

economic case that is reference, low-growth, or high-growth 

(reference is default); the year, from 2014–2018, at which to begin 

the calculation of LCC and PBP (2014 is default); and the number 

of simulation runs to be performed within a range of 100–50,000 

(10,000 is default). 

LCC & Payback Lists the input values used to calculate LCC and PBP. Many values 

were derived from data from sampled RECS households. 

Parameters include fuel type for water heating; annual numbers of 

loads; product lifetime; the discount rate applied to costs and 

savings; energy and water prices; the base-case efficiency 

distribution; product price and total installed cost; and energy and 
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water use. The result is annual and cumulative cash flow for both 

standard-sized and compact dishwashers operating at each 

efficiency level.

RECS Samples Presents the data from the 2480 RECS households DOE sampled 

for dishwashers. Identifies the parameters exported to (1) the LCC 

and PBP analysis (water heating and dryer fuel and price, numbers 

of washer and dryer loads per year); (2) equipment prices; (3) 

energy and water prices; and (4) discount rate (whether new or 

replacement unit). 

Energy & Water Use Contains per-cycle energy and water use data at each efficiency 

level broken down into machine energy use; hot water use; 

standby power; and water heating energy use (electric, gas, or oil).

Identifies the parameters exported to the LCC and PBP analysis.

Base-Case Efficiency Gives the market shares for efficiency levels in the base case.

Distribution

Equipment Prices Develops total installed cost for dishwashers in 2010$. Gives 

baseline and incremental manufacturer costs, retail price, sales tax, 

and installation cost for both product classes and each efficiency 

level. Includes the assumptions used about mark-ups and sales tax.

Energy & Water Prices Contains the regional prices in 2010$ for electricity, gas, oil, and 

water used in the LCC and PBP analysis. 

Energy Price Trends Displays the trends in energy prices for electricity, gas, and oil for 

2008–2046 under the reference, high, and low economic growth 

scenarios from AEO 2010.

Water Price Trend Contains the trend for water prices for 2008–2040 based on the 

consumer price index (CPI) 1975–2007.

Discount Rate Presents data used to develop average real discount rates and a 

distribution of discount rates for various types of household debt 

and equity used to purchase products installed in new homes and 

replacement products. Appendix 8E describes development of 

discount rates in detail.

Forecast Cells Gives details regarding base-case efficiency distributions for both 

classes of dishwashers. Median, minimum, maximum, and average 

values are given, along with 5th, 25th, 50th, 75th, and 95th percentile 

values. Included are product prices and details of the LCC and PBP 

(LCC savings in terms of money, energy, and water and the 
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percentages of households that would experience a net cost, no 

impact, or net savings from each efficiency level). 

Lifetime Presents the average lifetime, in years, for standard-sized and 

compact dishwashers (15.4), the Weibull parameters used for the 

survival function, and a graph of the Weibull retirement function 

for residential dishwashers.

8A.2 BASIC INSTRUCTIONS

Basic instructions for operating the LCC spreadsheet are provided below. 

1. After downloading the LCC file from DOE’s website, use Microsoft Excel to open 

it. At the bottom of the workbook, click on the tab for the sheet labeled Summary. 

2. Use Excel’s “View/Zoom” command in the top menu bar to change the size of the

display so that it fits your monitor.

3. Use the graphical interface in the spreadsheet to choose parameters or enter data. 

You can change the default choices for the three inputs listed under "User Input" 

(energy price trend, start year, and number of simulation runs). To change a default 

input, select the desired value from the drop-down choices by the input box.

4. After selecting the desired parameters, click the “Run” button. The spreadsheet will 

minimize until the simulation is complete, and will then re-open with the updated 

results.