APPENDIX 7 A

. LOAD USAGE FACTOR IN COMMERCIAL LAUNDRY
APPLICATIONS

TABLE OF CONTENTS

7A.1 INTRODUCTION

................................ ................................ ................................ ....... 7

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7A.2 METHODOLOGY AND DATA

................................ ................................ ................. 7

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7A.3 FINDINGS

................................ ................................ ................................ ................... 7

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LIST OF TABLES

Table 7A.1.1 Load Usage Factors from the Test Procedure

................................ .................. 7

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Table 7A.2.1 Cal UCONS Commercial Laundry Program: Number of monitored days
for each washer

................................ ................................ ................................ 7

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Table 7A.3.1 Load Usage Factors from the Cal

- UCONS Commercial Laundry Program

... 7

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LIST OF FIGURES

Figure 7A.3. 1 Distribution of Load Usage Factors

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7 A

- 1APPENDIX 7

- A. : LOAD USAGE FACTOR IN COMMERCIAL LAUNDR Y

APPLICATIONS

7A.1 INTRODUCTION

The purpose of this appendix is to clarify how the Department of Energy ( DOE ) made its estimates regarding the load usage factor (LUF) to address potential differences in loading practices between residential clothes washer usage and commercial clothes washer usage.

DOE’s current approach for estimating dryer energy use is based on the existing test procedure
for residential clothes washers. The approach utilizes the following equation to calculate the per

cycle energy consumption for removing moisture

–



## ( ) 

# ( ) ( ) 

# ( ) 

# ( ) DUF DEF RMC W LUF W LUF W LUF D

avg avg E × × × × + × + × = % 4

_ min min max max

Where:

LUF = load usage factor

, W = weight of test load [pounds (lb)/cycle],

RMC = moisture content that remains after washing (lb),

DEF = nominal energy required for a clothes dryer to remove moisture from clothes (0.5kWh/lb), and

DUF = dryer usage factor, a percentage of washer loads dried in a clothes dryer (0.91)

.

DOE implements the Load Usage Factor, as described in the current test procedure. As per this description, LUF
max , LUF min , and LUF avg are established as described below:

Table 7A.1.1 Load Usage Factors from the Test Procedure

LUF
max LUF avg LUF min Manual Fill 0.72

- 0.28 Adaptive Fill 0.12 0.74 0.14

Since the test procedure describes the load usage for a typical residential application, DOE analyzed data from available studies to establish loading practices in a commercial setting.

7A.2 METHODOLOGY AND DATA

For the purposes of understanding loading patterns, DOE looked at total water consumption as a proxy for loading. DOE collected data from the Cal

- UCONS Commercial Laundry Program,
which monitored clothes washers from different coin

- op erated laundromats or multifamily

7 A

- 2laundry rooms within the Southern California Gas Company (SCG) and the San Diego Gas and Electric Company (SDG&E) service territories. a The study conducted in situ monitoring of 50 clothes washers at selected properties, e ither common area laundry in multi

- family buildings or
coin

- operated laundromats. The CCW units included 21 clothes washers located at two
commercial coin

- operated laundromats and 32 clothes washers at four multi

- family properties,
for a total of 53 clothe s washers. Of these, only 6 coin

- operated laundromats monitored water usage. The monitored data included hot and cold water gallons dispersed at 5 minute intervals with indicators of a completion of a cycle. In order to assess loading, DOE only examined t hose washers that had gallons recorded for both cold and hot water. For all sites, only six clothes washers had data for gallons of hot and cold water. Two of these clothes washers were from th e same site (CCW#3 and CCW#4). Table 7 A.2.1 provides the number of days of data for each
clothes washer.

Table 7A.2.1 Cal UCONS Commercial Laundry Program: Number of monitored days
for each washer

. CCW #1 CCW #2 CCW#3 CC W #4 CCW#5 CCW#6

9 13 12 12 35 35

C

omputation of gallons per cycle The start of a cycle was denoted if the previous 5 minute data point had 0 gallons of water or if the previous 5 minute data point was flagged by the co mpletion of a cycle indicator. After the start of a cycle was noted, the gallons of water were then summed until a 5 minute data point was

f lagged as completion of a cycle.

We further categorized each cycle into different buckets based on their total g allons used during that cycle. The Load Usage Factor is described in the current test procedure.

7A.3 FINDINGS

Table 7 .A.3.1 shows the different Load Usage Factors for the six different clothes washers we analyzed from the Cal

- UCO NS Commercial Laundry Program. These are compared to the Load Usage Fact ors from DOE’s test procedure. The distribution of LUF min varies from 7% to 36%
across all six clo thes washers. A wide range of values is also apparent for LUF avg and LUF
max. Figure 7 A .3.1 shows the distribution for all clothes washers as well. CCW#1, CCW#5, and
CCW#6 are all located in multifamily homes. All other clothes washers are located in coin

operated Laundromats. Variability may also be due to different clothes washing behaviors of residents living multifamily buildings or customers washing at coin

- operated Laundromats

. However, we do not have enou gh data here to conclude this. Thus the variability of the data is problematic.

a PNNL 2008. Cal

- UCONS Commercial Laundry Program Measurement and Evaluation

- PNWD

- 3910.

7 A

- 3In addition, CCW#5 and CCW#6 are monitored for at least 20 more days than the rest of the clothes washers. This may explain why they have a couple of washing cycles with a high water usage, but the majority of thei r washing loads are around the average amount of water per cycle. Furthermore, all of these clothes washers are located in the Southern California area, which may not be representative of the U.S. population. However, since a nalysis of the Cal

- UCONS

Comme rcial Laundry Program does represent a section of the U.S population, DOE considers it
for a sensitivity analysis. For default LUF values, DOE has decided to use the load usage factors
from the current test procedure.

Table 7A.3.1 Load Usage Factors from the Cal

- UCON S Commercial Laundry Program

DOE TP CCW

#1 CCW

#2 CCW

# 3 CCW

# 4 CCW

# 5 CCW

# 6 Average

across CCWs

LUFmin 0.14 0.10 0.26 0.14 0.07 0.36 0.29 0.20 LUFavg 0.74 0.69 0.53 0.43 0.37 0.60 0.61 0.54

LUFmax 0.12 0.22 0.21 0.43 0.56 0.04 0.10 0.26

Figure 7A.3

. 1 Distribution of Load Usage Factors 0% 10% 20% 30% 40% 50% 60% 70% 80%

LUFmin LUFavg LUFmaxFrequency

DOE TP CCW #1 CCW #2 CCW #3 CCW #4 CCW #5 CCW #6

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