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NBSIR 79-1771

An Investigation of Preferences

for Various Types of Energy

Cost Feedback

er

Ann Ramey-Smith

Jennifer L. Gagnon

Consumer Sciences Division

Center for Consumer Product Technology

National Bureau of Standards

Washington, D.C. 20234

February 1979

Final Report

Issued August 1 979

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NBSIR 79-1771

AN INVESTIGATION OF PREFERENCES

FOR VARIOUS TYPES OF ENERGY

COST FEEDBACK

SEP 2 5 1979

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Ann Ramey-Smith

Jennifer L. Gagnon

Consumer Sciences Division

Center for Consumer Product Technology

National Bureau of Standards

Washington, D C. 20234

February 1979

Final Report

Issued August 1 979

Prepared for U.S. Department of Energy

U.S. DEPARTMENT OF COMMERCE, Juanita M. Kreps, Secretary

Luther H. Hodges, Jr., Under Secretary

Jordan J. Baruch, Assistant Secretary for Science and Technology

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director
, - >\ . u ,
Table of Contents

Page

List of Tables iii

List of Figures iii

Acknowledgments v

Abstract vii

Introduction ......... .... 1

Background 1

Present Study 2

Feedback Displays 3

Procedure ............. 4

Participants 4

Apparatus 4

Experimental Tasks ....... 7

Participant Response Categories .... 10

Results 12

Awareness-Attitudes Toward Energy Conservation . . 12

Response Categories 12

Cumulative Feedback Summary and Conclusions .... 24

Instantaneous Feedback Summary and Conclusions . . 25

Projected Feedback Summary and Conclusions .... 26

DOE Prototype Meter Summary and Conclusions .... 27

Participants’ Own Designs 28

Discussion 29

Related Research and Recommendations 29

Future Research Areas 32

References 34

Appendices 35

Appendix A, Table 1 —Appliance Energy Cost Values

Displayed for Cumulative Feedback 35

Appendix A, Table 2 —Appliance Energy Cost Values

Displayed for Instantaneous Feedback 36

Appendix A, Table 3 —Appliance Energy Cost Values

Displayed for Projected Feedback 37
Page

Appendix A, Table 4 —Literature Sources for Energy

Cost Estimates 38

Appendix B—Energy Usage Questionnaire 39

Appendix C—Feedback Explanation 43

Appendix D—Equipment Explanation 47

Appendix E--Cumulative Feedback Interview Guide . . 49

Appendix F—Instantaneous Feedback Interview Guide. 51

Appendix G—Projected Feedback Interview Guide . . 53

Appendix H~-Meter Design Interview Guide 55

Appendix I —DOE Prototype Meter Interview Guide . . 57

Appendix J—Final Interview 59

Appendix K—Human Factors Considerations for Energy

Feedback Meters 63

Appendix L—A Proposal for Field Testing Energy

Cost Feedback Meters 67
List of Tables

Table Page

1 Participant Demographics 5

2 Feedback Conditions 9

3 Understandability of the Purpose 13

4 Understandability of the Derivation .... 15

5 Usability for Budgeting 17

6 Usability for Monitoring Individual

Appliance Use . 19

7 Usability for Comparing Patterns of Energy

Use 21

8 Meaningfulness 23

List of Figures

Figure Pa9e

1 Interactive Terminal and Feedback Display

Panel 6

iii
'
Acknowledgments

The authors of this report wish to acknowledge the

assistance of J.J. Persensky and John V. Fechter, Jr. in

the preliminary stages of the study's design, Robert Kershner

and George Lapinsky for their aid in data collection and

reduction, the staff of the Advanced Measurement Technology

Group at NBS for equipment design and construction, and

Michael Vogt of the Center for Building Technology at NBS

for the development of the required computer programs

.

Thanks are also due Bonnie Matteson, Carol Muliinix, and

Kim Leaman for secretarial support.

v

ABSTRACT

The present study addressed the issue of consumer

preferences for various types of energy cost feedback for

individual consumers. Its purpose was to provide human

factors recommendations to DOE related to the performance

characteristics of energy cost feedback devices for use

by DOE in testing energy cost feedback meters. Simulation

and interview techniques were used to provide consumer

reaction to cumulative, instantaneous, and projected

feedback presented as dollar and cent values. A majority

of participants indicated a preference for cumulative

feedback types. All types of cumulative feedback are easily

understood, accurate in reflecting actual energy consumption

and suitable to several uses. Hourly instantaneous feedback

was considered useful for monitoring energy use of individual

appliances. All participants having two energy sources

in their home expressed a preference for having feedback

presented as separate cost figures rather than as a total

cost. Recommendations for feedback types as well as some

performance characteristics of energy cost feedback meters

for further testing by DOE are discussed.

vii
.

’

.

.
INTRODUCTION

Background

Within the Department of Energy (DOE) , the Division

of Buildings and Community Systems, Office of the Assistant

Secretary for Conservation and Solar Applications, has

responsibility for encouraging more efficient use of energy

in the building sector. It is becoming more evident that

motivating the consuming public, as well as developing

new technologies, is a crucial dimension to the conservation

effort. One strategy currently being developed involves

the concept of feedback. In this context feedback means

providing homeowners with immediate and understandable

information on their energy costs will allow them to better

control their energy using activities.

In research funded by DOE's Consumer Motivation Branch

and conducted by Princeton University, a series of experiments

tested this concept. Seligman, Darley, and Becker (1976)

performed four feedback experiments designed to: (1) modify

the rate of summer electricity usage by providing homeowners

daily feedback on electricity usage as compared to their

previous month’s consumption; (2) examine the effects of

setting specific energy conservation goals on electricity

consumption; and, (3) determine the extent of energy consumption when a homeowner's energy consumption feedback involved

a comparison to other peoples' energy consumption. Seligman

et al. concluded that feedback facilitates a reduction

of energy consumption but that the optimal nature of the

feedback system had not been identified.

Since then, a number of other research projects have

addressed the issue of feedback. For example, Winett,

Kaiser, and Haberkorn (in press) investigated daily feedback and rebate systems on energy used by lighting, appliances,

and air-conditioning. Their results indicate that daily

feedback is effective in reducing electricity consumption

when preceded by a rebate system for reductions in electricity use. However, the effects of feedback alone were

inconclusive. Consequently, Winett, Neale, Williams, Yokley,

and Kauder (1977) evaluated three kinds of daily written

cumulative feedback systems; i.e., individual feedback,

group feedback (based on energy used by similar types of

residences) , and the combination of individual and group

feedback. The feedback presented was kWh use for the prior

day and the percent increase or decrease from the baseline

use and contained a projective feedback component. Winett

et al. found that the combination of individual and group
feedback was best in reducing electricity consumption,

while group feedback alone was the most ineffective of

the three types of feedback.

The Consumer Motivation Branch of the Department of

Energy, in cooperation with Potomac Electric Power Company

(PEPCO) and with research support from Princeton University,

is currently testing the effectiveness of a simple feedback

monitor which provides homeowners with a display that alternates, at four second intervals, time of day and centsper-hour of total household electricity use (i.e., "Your

electricity cost for the next hour will be $0,742 if you

continue to use electricity at your present rate."). This

field experiment involves 140 PEPCO customers (70 control

and 70 experimental) and will run for one year. It is

not designed to address the question of the most effective

type of feedback, but rather as a preliminary study to

advance knowledge in the area of feedback as it relates

to customer acceptance, utility roles, and technical

considerations

.

Present Study

As an initial investigation of the issue of effective

energy feedback, the present study provided consumer input

to the human factors design of energy feedback meters.

Toward this purpose, several assumptions are made. These

are

(a) Energy feedback meters are an effective means

of reducing energy consumption;

(b) The meters in question will be consumer-oriented

rather than for use by industry;

(c) The meters will provide energy-use information

specific to the individual consumer as opposed

to a group; and,

(d) The energy-use information will be presented as

cost figures rather than as, for example, kWh.

The purpose of the present study is to provide human

factors recommendations related to the performance characteristics of energy-cost feedback devices. Role-playing and

interviewing techniques are used to provide consumer reaction to various types of energy cost feedback. The issues

addressed include:

1. The meaningfulness/usability of the displayed

energy feedback information;

2
2. The design characteristics of the meter itself;

and,

3. Educational or instructional materials which

should accompany the feedback meters in field

testing.

This report presents findings regarding the first

issue above, with a brief discussion of human factors recommendations for design characteristics contained in

Appendix K. The issue of educational and instructional

materials will be addressed in a separate report.

Feedback Displays

The three types of energy-cost feedback to which participants were exposed include cumulative, instantaneous,

and projected feedback presented as dollar and cent values.

For all three types of feedback, energy cost was presented

as a total energy cost or was broken down into gas and

electric costs separately. These three feedback types

are defined below as they were conceptualized for this

study

.

A cumulative feedback meter constantly monitors energy

usage and displays a running accumulation of the cost of

energy consumption for daily, weekly, or monthly time periods.

At the end of the time period, the display resets and the

accumulation begins again. Without any prior knowledge

of how consumers would use cumulative feedback, it was

hypothesized that this type of information would be most

useful for budgeting energy expenditures and for making

comparisons of energy use on a day-to-day basis.

An instantaneous energy-cost feedback meter monitors

the rate of present energy usage and estimates what the

cost would be if consumption continued at that rate for

one hour, one day, or one month. The meter samples energy

use and updates the display every 15 seconds. It was hypothesized that consumers could use instantaneous feedback

as an indicator of the energy consumption of various individual

appliances or behaviors.

The third type of energy cost feedback is projected

feedback . Projected feedback is based on the previous

day ' s energy cost which is used to estimate the energy

cost for the following day, week, or month. The values

displayed for each time period change each day based on

the energy cost of the previous day. Project feedback,

3
as used in the present study, was hypothesized to serve

as an estimate for use in budgeting energy use and cost

for up to one month

.

PROCEDURE

Participants

Eighteen participants were tested during a five-week

period. Participants were selected such that each of the

following age groups contained six participants: 25-39

years, 40-54 years, and 55+ years. All participants were

residents of the Washington, D.C. metropolitan area and

are not intended to be statistically representative of

energy consumers nationwide.

Except for the 55+ years group in which three participants

had gas and electric homes and one had an oil and electric

home, each group had two participants who lived in allelectric homes, two in oil and electric homes, and two

in gas and electric homes. While it was not possible within

each category to have a range among the participants of

the percentage of take-home pay spent on utilities, a range

of two percent to 20 percent did exist across age groups

and home energy source categories. Table 1 presents a

summary of the demographic characteristics of the study

participants

.

Each participant was tested for two hours per day

for four consecutive days. Participants were paid $3.00

per hour plus a bonus of $1.00 per hour for those who completed

the four-day test period.

Apparatus

Energy cost information was presented on a panel housing

six LED (light emitting diode) displays, as shown in Figure

1. A computer generated the displayed dollar and cent

values which were calculated from the energy usage for

a sample of appliances. Scenarios were developed representing

various amounts of energy usage for both summer and winter

seasons and for electric homes and gas and electric homes.

Appendix A provides cumulative, instantaneous, and projected

energy cost values associated with summer and winter usage

of each of the appliances included in the study. Cumulative

and projected values were based on average appliance usage.

Whereas instantaneous values were derived from kilowatt

hour energy consumption. Appendix A also includes literature sources for the energy-cost values.

4
TABLE 1

Particioant

Demographics

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FIGURE 1

Interactive Terminal and

Feedback Display Panel

6
Also shown in Figure 1 is an interactive terminal

that allowed participants to simulate appliance usage by

turning the appliances included in the sample on or off.

The participants were able to study the displayed values

and to note changes in the energy cost information as a

result of their simulated energy-using activities. Interviews with participants were aduio-taped to facilitate

later data compilation.

Experimental Tasks

At the present stage of research concerning the most

effective type of energy cost feedback, all the relevant

goals and hypotheses have not yet been identified, and

consequently the appropriate measures to make have not

been specified. Therefore, individual interviewing techniques

similar to those used in focus group interviewing were

used. Interviewing techniques were employed because they

have been previously shown to be useful in guiding policy

decisions and serve as a way to confirm thoughts and suspicions,

to suggest new ideas and hypotheses , and to identify appropriate consumer language . The general purpose of the interviews was to identify the pertinent issues and concerns

regarding energy cost feedback.

Each subject participated in a series of conditions

designed to illustrate the various feedback types and obtain

participant responses to each. These conditions were designed

such that for each feedback type, the participant was

presented with a scenario of appliance usage which was

displayed on the screen of the interactive terminal. The

scenarios represented average or typical energy consumption

of several appliances. The participant was able to look

at the screen to see which appliances were on and what

the thermostat settings were, and then note the cost values

displayed on the LED display panel for that particular

feedback type. The participant could then simulate changes

in appliance usage through the interactive terminal. These

changes would, in turn, result in changes in the cost values

shown on the LED display. Through this iterative process,

each participant was educated as to (1) the kinds of values

they could expect to see if they had a feedback meter in

their own home that was actually connected to their energy

supply and (2) how their energy usage behavior would affect

those displayed values. The experimenter used a discussion

guide to help the participants discuss a wide variety of

issues related to each type of energy cost feedback.

On Day 1, participants:

o completed an energy usage questionnaire designed

to determine their attitudes and awareness toward

energy usage and conservation.

7
o were familiarized with the definitions of and

differences between the three types of energy feedback being examined; and

o were briefed on the tasks to be completed during

the remainder of their participation, including

a demonstration of the apparatus.

The interview materials used in each of the above Day

1 tasks are presented in Appendices B, C, and D.

On Days 2 and 3 , participants were shown each type

of energy-cost feedback. After exposure to each of the

feedback types, participants were interviewed to determine

their reactions to the feedback type, their impressions

of the meaningfulness and usability of the displayed values,

their preferences for time periods, and their preferences

for total versus separate energy cost figures. The reader

should refer to Appendices E, F, and G for the interview

guide associated with each feedback type.

Table 2 shows the feedback conditions to which each

participant was exposed. When examining these various

combinations, participants were allowed to choose whether

they would view summer appliance usage values or winter

appliance usage values.

Participants who lived in all-electric homes viewed

energy cost values for electric appliances only, and those

participants with gas-and-electric or oil-and-electric

homes were shown energy costs for a combination of electric

and gas appliances. This assignment to conditions was

employed because it was felt that all-electric home owners

would be merely speculating about whether they would want

a total display or separate displays of energy sources.

On the other hand, those participants with two-energy-source

homes would be better able to make a judgment as to whether

they would want their utility costs shown as combined or

separate costs.

The sample size (N = 18) allowed for presentation

of feedback type (cumulative, instantaneous, and projected)

to be counter-balanced so that any order effects present

would not bias the results. Each participant was exposed

to the time periods in an order ascending from the shortest

time period to the longest. For subjects with gas and

electric or oil and electric homes, total energy costs

were presented first, followed by gas and electric costs

separately.

8
Feedback

Conditions

Monthly

Monthly

Cumulative

Feedback

(MCF)

Monthly

Instantaneous

Feedback

(MIF)

Monthly

Projected

Feedback

(MPF )

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On the third day of participation, subjects were also

asked to design their preferred energy cost feedback meter.

If the design involved more than three displays, the participant was then asked to limit the meter to three displays.

Interviewing was conducted to determine why each participant

preferred that combination of information displays on a

feedback meter. Appendix H shows the interview guide used

to discuss the participant’s meter design.

On the fourth and final day, participants were shown

an energy-cost feedback meter which was based on input

from DOE's Consumer Motivation Branch personnel. The

prototype incorporated three displays providing the following

types of information:

Display 1 - Hourly Instantaneous feedback on

energy usage;

Display 2 - Daily Cumulative feedback on energy

usage; and.

Display 3 - Monthly Cumulative feedback on

energy usage.

For each of the displays, participants were queried as to

whether the information displayed should be presented as

a total energy figure or whether energy usage should be

broken down into its two energy sources, i.e., gas and

electric

.

Additionally, for Display 2, participants discussed

whether the previous day's energy cost should be stored

and, if so, for how long it should be stored. Appendix

I shows the questions which the participants were asked

regarding the prototype meter design.

A final interview (see Appendix J) was conducted to

assess participant's knowledge of energy cost feedback

and their preferences for energy cost information. In

addition, participants were asked what instructional materials

should accompany the proposed meters for consumer use.

Participant Response Categories

Participants' responses to the types of energy-cost

feedback were coded to summarize the information obtained

through interviews. The following response categories

represent issues and reactions revealed during interviewing:

10
o Understanding the purpose of each feedback

display—do the participants understand the

nature of the information displayed? Do the

participants have reservations about the purpose?

o Understanding how the feedback information was

derived—do the participants understand how the

displayed values were determined? Do the

participants feel the derivation is clear and

accurate? Do the participants like the

derivation?

o Usability—how do participants say they would

or could use each type of feedback? The specific

uses which the participants mentioned most often

are listed below:

- for budget management—would participants compare

the displayed values to their individual utility

and/or household budgets?

- for determining energy consumption cost of

individual appliances,

- for identification and comparison of differing

patterns of energy use

o Meaningfulness —do the participants feel that the

feedback type has meaning to them? Does the feedback information have face validity? Is the

information accurate and realistic? Meaningfulness

is related to how and if a feedback type would be

used by consumers to help conserve energy and the

amount of instructional information which must accompany the feedback meter for residential use.

Notes taken during interviews as well as recordings

of daily sessions were reviewed to assess participants'

answers to questions and opinions about feedback. Comments

were classified as being positive, negative, or non-committal (where a non-committal comment refers to no comment,

a neutral comment, or a comment too vague to categorize)

.

Only those comments which were definite affirmations or

negations were classified as such, with other responses

assessed as non-committal.

11
RESULTS

The findings presented below are based on a small

sample. The sample was not intended to be statistically

representative of the general population and hence quantitative

projections should not be made. It is nevertheless believed

that the attitudes expressed are illustrative of those

that exist in the population at large.

Awareness-Attitudes Toward Energy Conservation

A questionnaire was used to assess participant's awareness

of and attitudes toward energy conservation prior to learning

about energy cost feedback. Three out of eighteen participants

were able to accurately report the portion of their income

spent on utilities. Only one person reported that she

knew how the utility company computed charges for energy

use. All participants reported that they actively do or

have done things to conserve energy in the home, with one

person reporting that she occasionally checked her electricity

meter

.

When asked whether additional energy conservation

information would be beneficial, seventeen of the participants

reported that some sort of additional information would

help them conserve energy in the home. Specifically, two

people wanted information on home insulation; eleven people

wanted information on energy used by various appliances;

two people wanted general information on energy conservation;

two wanted to know the amount of energy they used per day

or for some defined time period; and, one person wanted

to know during what times energy is least expensive. This

energy conservation information could be provided through

a variety of educational programs or materials as well

as by means of a feedback device.

Response Categories

Participants' responses to cumulative, instantaneous,

and projected feedback and the DOE Prototype meter are

summarized in this section. Responses are presented for

each response category separately with data presented as

the frequency and proportion of responses that are positive,

negative, and non-committed for each response category.

UNDERSTANDABILITY OF THE PURPOSE—Table 3 presents

the numbers and proportions of positive, negative, and

non-committed responses for each time period of cumulative,

instantaneous, and projected feedback and the DOE prototype

12
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Values

in

rows

with

headings

"Cumulative

Feedback,"

"Instantaneous

Feedback,"

and

"Projected

Feedback"

are

the

total

frequencies

and

proportions

of

positive,

negative,

and

noncommittal

responses

across

the

three

time

periods

for

those

feedback

types.

**The

total

number

of

possible

responses

to

each

time

period

equals

the

number
meter. Predominantly favorable responses were received

concerning the understandability of the purpose of daily,

weekly, and monthly cumulative feedback. Cumulative feedback,

as a record of actual energy use, appears to be simple

and easily understood by the consumers sampled. Only one

participant reported having problems with understanding

the purpose of weekly cumulative feedback.

Of the three types of instantaneous feedback, the

proportion of positive responses for hourly instantaneous

feedback is the largest. More positive than negative responses

were made only to hourly instantaneous feedback. Generally,

The participants felt that the purpose of estimating energy

cost from a current sample of energy use was unclear when

trying to estimate to a time period of more than one hour

since the energy use sampled can vary considerably.

A majority of responses concerning the understandability

of the purpose of projected feedback were favorable.

Generally, the purpose of all three types of projected

feedback is understandable, with daily projected feedback

being more easily understood than the other projected time

periods

.

Responses to the DOE prototype meter indicated that

the purpose of daily cumulative feedback and monthly cumulative

feedback were more understandable than hourly instantaneous

feedback. The responses to daily cumulative feedback and

monthly cumulative feedback were overwhelmingly positive,

with hourly instantaneous feedback receiving fewer favorable

responses

.

UNDERSTANDABILITY OF THE DERIVATION—As indicated

in Table 4, the proportion of positive responses across

the three types of cumulative feedback combined was 0.57,

with only one negative response reported to the derivation

of monthly cumulative feedback. The problem reported in

understanding monthly cumulative feedback was in remembering

that the value is derived from continuous cumulation of

energy cost for an entire month—a problem that may have

been due to the experimental setting. The derivation of

cumulative feedback as energy actually used seems to be

well understood and a desirable characteristic of energy

cost feedback.

The derivation of instantaneous feedback using current

energy usage to estimate to some future time period was

not easily understood by the participants. The responses

to the derivation of instantaneous feedback were primarily

14
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negative. Of the three instantaneous time periods , the

derivation of hourly instantaneous feedback was best understood

but received only five positive responses.

The assumption that the instantaneous values displayed

reflect energy cost if energy is used continuously at its

present rate was regarded as invalid by the consumers sampled.

Daily instantaneous feedback and monthly instantaneous

feedback exacerbate this problem since they assume that

energy is used continuously at the same rate for an entire

day or month. A longer sample time was considered desirable

for deriving instantaneous feedback values in order to

get a more accurate estimate of actual energy usage.

The derivation of projected feedback received mixed

reactions. The derivation of daily projected feedback was

considered the most understandable with more positive than

negative responses. Both weekly projected feedback and

monthly projected feedback received more than twice as

many negative as positive responses. Some participants

felt that projected feedback should not be based on the

previous day's energy cost but on some average of days

(e.g., the average of a week's energy cost) to reduce varia

variability and facilitate budget estimates.

Responses to the derivation of the displays included

in the DOE prototype meter indicated that participants

tended to understand the derivation of each of the three

feedback types. When the responses to the understandability

of the derivation of hourly instantaneous feedback (0.67)

are compared to the responses to the understandability

of the purpose of hourly instantaneous feedback (0.28)

in the DOE prototype meter display, a discrepancy is noted.

It seems that the majority of the participants understand

how hourly instantaneous feedback was derived but some

had difficulty in understanding why.

USABILITY FOR BUDGETING—Table 5 presents responses

to the usability for budgeting of each type of feedback.

The use of cumulative feedback for budgeting energy expenditures received a total of 37 positive responses. Daily

cumulative feedback and monthly cumulative feedback were

most favorably viewed for budgeting considerations. While

there were no negative responses to weekly cumulative

feedback, responses were evenly divided between positive

responses and non-committed responses, meaning that half

of the participants did not mention the usefulness of weekly

cumulative feedback for budgeting.

16
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17
Overall, study participants did not consider instantaneous

feedback to be very useful in helping them budget energy

expenditures. Hourly instantaneous feedback received as

many positive as negative responses regarding this use.

Daily instantaneous feedback and monthly instantaneous feedback received more negative than positive responses with

the participants indicating that the estimates were unrealistic

since they would be very high if several high-energy-using

appliances happened to be on at the same instant.

All types of projected feedback were favorably considered

for budgetary use, with monthly projected feedback receiving

the most favorable reaction for budgetary use.

In the DOE prototype meter daily cumulative feedback

and monthly cumulative feedback were both considered more

favorably than hourly instantaneous feedback for use in

monitoring the energy budget. Hourly instantaneous feedback

received no positive responses and a large proportion of

non-commit ted responses. Hourly instantaneous feedback seems

to have little utility for budget management in the opinion

of the participants.

USABILITY FOR MONITORING INDIVIDUAL APPLIANCE USE —

A summary of participants' responses to the usability of

the various types of energy-cost feedback for monitoring

individual appliance use are presented in Table 6.

Daily cumulative feedback was the preferred type of

cumulative feedback for monitoring individual appliance

usage, while the weekly cumulative feedback and monthly

cumulative feedback time periods were considered less useful

for this purpose. This use of cumulative feedback was

considered to be a short-term use; i.e., consumers would

not need to continue monitoring individual appliances once

they learned about the cost of using various appliances.

More positive responses were made to the use of instantaneous

feedback to monitor the energy use of various individual

appliances than any other possible uses of instantaneous

feedback. Hourly instantaneous feedback received a majority

of the positive responses with daily instantaneous feedback

and monthly instantaneous feedback receiving fewer positive

responses

.

It should be noted that using hourly instantaneous

feedback to monitor energy use of individual appliances

would probably be a temporary behavior only. Participants

noted that once they had learned the cost of using various

appliances they would no longer need to monitor feedback

information for this purpose. Participants also noted

18
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19
that they could obtain this information from sources other

than an energy feedback device (e.g. published conservation

brochures and pamphlets)

.

Overall, projected feedback does not lend itself well

to use for estimating cost of using individual appliances.

Since projected feedback values are estimates based on

a day's total energy cost, it has limited usefulness for

monitoring small portions of total energy use. Only daily

projected feedback received any positive comments with

all three types of projected feedback receiving more noncommitted than positive or negative responses.

When viewing the DOE prototype meter, five participants

favorably responded to the usability of cumulative feedback

for determining energy consumption of various appliances,

but the majority of responses to cumulative feedback's

usability for monitoring individual appliance use were

non-committal. Individual appliance monitoring may be

the most valuable use of hourly instantaneous feedback, as

seven participants made positive responses to this use

of hourly instantaneous feedback, while only one participant

responded negatively.

COMPARING PATTERNS OF ENERGY USE—Table 7 contains

data on participants' responses to using cumulative, instantaneous and projected feedback to compare patterns of energy

use (e.g. from one week to another or one season to another)

.

For all types of feedback, more non-committed than committed

responses were made.

Overall, this use of cumulative feedback received

16 positive responses. The only negative response was

made to monthly cumulative feedback. Of the three types

of cumulative feedback, daily cumulative feedback was preferred

for comparing patterns of energy use as it allowed comparison

of daily activities. Participants felt that this use of

daily cumulative feedback could be aided by a device which

would save the previous day's cumulative value.

The use of instantaneous feedback to compare patterns

of energy use received few overall positive responses.

Hourly instantaneous feedback was the only type of instantaneous

feedback which received any positive responses for use

in comparing patterns of energy use. Instantaneous feedback

is designed to update energy readings and make new estimates

of energy cost every few seconds. Such variability apparently

does not lend itself to comparisons among long time periods,

such as between months or seasons.

20
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21
The use of projected feedback to compare patterns

of energy use received 15 positive responses. Of the three

projected feedback time periods, daily projected feedback was

considered the most usable for comparing patterns of energy

use with nine positive responses, while weekly projected

feedback and monthly projected feedback were both viewed

less favorably for this purpose.

An inspection of Table 7 indicates that, when viewing

the DOE prototype meter, eleven of the participants said

they could use daily cumulative feedback to monitor patterns

of energy use, compared to six participants who indicated

that they could use monthly cumulative feedback for this

purpose. Only one of 18 participants indicated they could

use hourly instantaneous feedback to monitor energy use

patterns. Consequently, of the three DOE prototype meter

displays, daily cumulative feedback was considered most

favorably for use in comparing patterns of energy use.

MEANINGFULNESS—Table 8 presents data on the meaningfulness of cumulative, instantaneous, and projected feedback.

Both cumulative and projected feedback received more noncommitted than committed responses, whereas instantaneous

feedback received predominantly negative responses.

Responses to cumulative feedback's meaningfulness

indicated that daily cumulative feedback was considered

most meaningful, monthly cumulative feedback less meaningful

and weekly cumulative feedback least meaningful. Generally,

the participants liked seeing their cost of energy as they

used it and found a daily value easiest to work with.

They felt that daily cumulative feedback could be used

to estimate costs for longer time periods.

Instantaneous feedback in general was not regarded

as highly meaningful with only seven positive responses

compared to 40 negative responses. Participants found

instantaneous feedback a new concept that did not seem

entirely accurate. Daily instantaneous feedback and monthly

instantaneous feedback received a large proportion of negative

responses which suggests that these forms of instantaneous

feedback had little meaning for participants. Hourly

instantaneous feedback was considered somewhat more understandable, but negative responses outweighed positive responses.

Five positive responses as compared to 20 negative

responses reflects the lack of meaningfulness of projected

feedback. Overall, participants felt that projected feedback

was not considered meaningful because daily variations

in energy use would not be accounted for accurately in

projected energy cost estimates. That is, if the previous

22
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23
day's activities required an inordinately high use of energy

(as on house cleaning day) , projected values would not

represent realistic estimates of weekly or monthly costs.

Of the values displayed for the DOE prototype meter,

the meaningfulness of daily cumulative feedback and monthly

cumulative feedback received larger proportions of positive

responses than hourly instantaneous feedback. When compared

with responses to hourly instantaneous feedback when it

was presented alone and not as part of the prototype meter,

it appears that hourly instantaneous feedback values are

highly meaningful neither when they are shown alone nor

when presented in combination with other types of feedback.

Cumulative Feedback Summary and Conclusions

Daily cumulative feedback is easily understood in

terms of its purpose and derivation. All committed reactions

to its meaningfulness were positive. Daily cumulative feedback is more likely to be used to obtain information on

energy consumption of individual appliances and for comparing

patterns of appliance usage than either weekly cumulative

feedback or monthly cumulative feedback. All committed

responses regarding budgetary uses of daily cumulative feedback were positive.

The drawbacks of daily cumulative feedback include

1) the inconvenience of checking the values each day, 2)

the record keeping required to determine energy consumption

of individual appliances, and 3) the possibility that if

daily cumulative feedback is used to monitor effects of

changing appliance usage individually, the relatively small

value changes may decrease the motivation to conserve on

usage of small energy users.

Weekly cumulative feedback's purpose and derivation

appear understandable. Based on positive responses, it

does not seem as likely to be used for budgetary concerns

as either daily cumulative feedback or monthly cumulative

feedback. Both weekly cumulative feedback and monthly

cumulative feedback were not responded to as favorably

as was daily cumulative feedback for gaining information

on individual appliance consumption and patterns of energy

usage. In addition, weekly cumulative feedback does not

appear to be as meaningful as either daily cumulative

feedback or monthly cumulative feedback.

Daily cumulative feedback and monthly cumulative

feedoack received relatively large numbers of positive

responses regarding understandability of derivation, purpose,

and budgetary uses. However, the participants' responses

indicated that they would not be as likely to use monthly

24
cumulative feedback as they would use daily cumulative

feedback to monitor individual appliance energy consumption

or compare patterns of energy usage. In addition, more

positive responses were made to the meaningfulness of daily

cumulative feedback than to monthly cumulative feedback.

According to participants, the main benefit of monthly

cumulative feedback is its usefulness in budgetary matters

and the corresponding likelihood that consumers will decrease

energy consumption if their cost of usage is exceeding

the utility allocation in their budget.

Across the six response categories, daily cumulative

feedback and monthly cumulative feedback are the most preferred

forms of cumulative feedback. The difference in how they

would be used concerns their usability for monitoring the

energy cost of individual appliances. Eleven participants

said they could use daily cumulative feedback for this

purpose, as compared to two participants who said they

could use monthly cumulative feedback in this manner. Daily

cumulative feedback requires record keeping if consumers

are to use it to determine how their energy cost to-date

compares to their utility budget. Its benefit is that

it may encourage consumers to attend to energy conservation

on a daily basis. Monthly cumulative feedback does not

require record keeping in order to compare energy cost

to-date to the utility budget. In addition, the increasingly

larger numbers displayed by monthly cumulative feedback may

make consumers more aware of the ultimate consequence of

their behavior than would daily cumulative feedback.

Instantaneous Feedback Summary and Conclusions

Although primarily positive responses were made to

the purpose of hourly instantaneous feedback, hourly instantaneous feedback received fewer positive than negative

responses regarding its derivation and meaningfulness.

Only three positive reactions were made to using hourly

instantaneous feedback for budgetary purposes and for

comparing patterns of energy use . The main advantage of

hourly instantaneous feedback is its perceived usefulness

in determining the relative energy cost of individual appliances .More negative than positive responses were made to

daily instantaneous feedback for each of the six response

categories. Participants saw little utility of daily instantaneous feedback and overwhelmingly felt that it was not

providing meaningful information. Monthly instantaneous

feedback suffered the same adverse reactions as did daily

instantaneous feedback. The difference in reactions to

25
monthly instantaneous feedback and daily instantaneous

feedback is one of degree, with monthly instantaneous

feedback generally receiving more negative and fewer positive

reactions

.

In summary, hourly instantaneous feedback was generally

the preferred form of instantaneous feedback, while daily

instantaneous feedback and monthly instantaneous feedback

were viewed by the participants as having little or no

utility. Problems were encountered with hourly instantaneous

feedback however. These included:

1) difficulty in grasping the underlying

assumption of continuous appliance operation

for one hour;

2) the inaccuracy of the values displayed with

regard to actual cost due to the disparity

between the assumption of continuous operation

and how long appliances are actually used;

3) its limited utility in budget matters; and,

4) its questionable appropriateness for providing

individual appliance energy consumption information . Projected Feedback Summary and Conclusions

Daily projected feedback received the largest number

of positive responses across response categories among

the three forms of projected feedback. One notable exception is usability in budgetary matters for which monthly

projected feedback received more positive responses. Participants' responses indicated that they felt that daily projected

feedback provides the same information as saving yesterday's

daily cumulative feedback. The general reaction to saving

that figure was positive, and participants felt that yesterday's cost information should be provided on a feedback

meter if the cost of doing so is not substantial.

Primarily positive responses were made to weekly

projected feedback's purpose and usability for budgeting,

with a small proportion of positive responses made to its

derivation and usability for comparing patterns of energy

use. No positive reactions were made to using weekly projected

feedback for the identification of individual appliance

energy usage cost. The main drawback of weekly projected

feedback is its lack of meaningfulness.

26
As with the other forms of projected feedback,

participants did not view monthly projected feedback as

being very meaningful. Participants made more positive

responses to using monthly projected feedback for budgetary

purposes than either daily projected feedback or weekly

projected feedback. The large proportion of non-committal

responses to the use of monthly projected feedback for

comparing patterns of energy use suggests that this use

was not very obvious to the participants. No positive

responses were made to using monthly projected feedback

for monitoring individual appliance use. As with daily

projected feedback and weekly projected feedback, participants

generally responded positively to understanding the purpose

of monthly cumulative feedback but less favorably to understanding the derivation.

In summary, daily projected feedback was the preferred

type of projected feedback. However, monthly projected

feedback was responded to more favorably for its usability

in budgeting. Generally, the participants seemed to want

to use feedback to either help them budget or determine

the effectiveness of various energy conservation measures.

Apparently, projected feedback as it has been derived does

not provide the desired information in an easily understood

and meaningful way. Perhaps a form of projected feedback

that would be more meaningful and usable would be one which

uses the monthly cumulative cost to date and projects that

value to the end of the month. That is, if the cumulative

cost at the end of the first week of the month was $10.00,

then the projected monthly cost would be $10.00 X 4 weeks,

or $40.00.

DOE Prototype Meter Summary and Conclusions

Based on participants' responses to the DOE prototype

meter, daily cumulative feedback and monthly cumulative

feedback fare well; in all cases the positive comments

outweigh the negative comments. For all the response categories there were relatively few or no negative comments

directed at cumulative feedback.

On the other hand, the opposite seems to be true for

hourly instantaneous feedback. The participants had difficulty

grasping the meaning of the hourly instantaneous feedback

information. Although they understood how hourly instantaneous feedback was derived, they had problems understanding

its purpose. The participants expressed little use for

hourly instantaneous feedback for monitoring budgets or

patterns of energy use. Its strongest positive point is

that hourly instantaneous feedback was considered useful

27
for monitoring individual appliance energy use by more

participants than daily cumulative feedback and monthly

cumulative feedback combined. However, this still represents

less than a majority opinion—seven of 18 participants.

In addition, the prevailing opinion among the participants

was that hourly instantaneous feedback would either only

be used for the first couple of weeks, or that it was not

accurate and yielded unrealistic information and would

consequently not be used at all.

Participants* Own Designs

Participants were asked to choose the particular

combination of feedback information that they would like

to have for their own use. If a participant chose more

than three different kinds of information displays, they

were asked to limit their choices to only three displays.

Sixteen out of 18 participants chose to include some

form of cumulative feedback for their own use. Of these,

daily cumulative feedback was the preferred form of cumulative

feedback, being chosen by six participants. Four participants chose weekly cumulative feedback while two chose monthly

cumulative feedback. Two participants chose daily cumulative

feedback and monthly cumulative feedback in combination,

while one person preferred the daily cumulative feedback and

weekly cumulative feedback combination. One person wanted

all three types of cumulative feedback included in the

feedback meter design.

Six out of 18 participants chose to include some form

of instantaneous feedback for their own use. Of those

consumers who expressed a preference for instantaneous

feedback, five chose hourly instantaneous feedback while

one person preferred daily instantaneous feedback.

Three out of 18 participants chose to include some

form of projected feedback in their own feedback meter

design. Of these, one person preferred daily projected

feedback, one preferred monthly projected feedback, and

one preferred daily and weekly projected feedback in combination.

All participants having two energy sources in their

home (e.g., oil and electric or gas and electric homes)

expressed a preference for having feedback presented as

two separate values rather than a total cost. Participants

felt that such separate cost displays would help them better

determine which energy source (e.g., gas or electric) was

accounting for the larger portion of the overall energy

cost. This knowledge would in turn help the consumer plan

future conservation measures and evaluate previous measures.

28
Answers to a final written questionnaire verified

that cumulative feedback was the overall preferred form

(for 16 participants) of feedback information, with the

remaining two participants preferred instantaneous feedback.

DISCUSSION

Related Research and Recommendations

The results of the present study lend support to previous

work done in the area of feedback. Several hypotheses

have been suggested to explain why feedback facilitates

residential energy conservation and what characteristics

effective feedback should have. Some of the hypotheses

and their relevance to the present study are discussed

below.

Participants' answers to questions designed to assess

attitudes toward and awareness of energy conservation revealed

that consumers are motivated to conserve energy but need

information to teach them about energy consumption of appliances and conservation behaviors leading to greater energy

savings. According to the human factors approach, "feedback

teaches people how to make appropriate conservation responses"

(Seligman, 1978) . Seligman contends that this explanation

of feedback as a form of trial and error learning does

not apply in energy conservation situations since homeowners

can learn about successful techniques for reducing energy

consumption from sources other than by feedback. Consequently,

Seligman maintains that when homeowners already know conservation measures, feedback does not facilitate energy conservation through teaching new, skilled responses. Rather,

it keeps the idea of conservation salient and it frequently

shows the consumer how he is doing in achieving some goal.

In view of the fact that consumers can learn about

energy conservation measures from a variety of sources,

the use of feedback as a method of determining energy consumption of various appliances was considered nonessential

by participants. Participants reported that their reliance

on a feedback display to provide information about effective

conservation measures would be short-lived. That is, once

they had this information they felt that they would no

longer need to rely on a feedback device for this information.

This reaction by the participants has particular relevance

to instantaneous feedback. According to study participants,

the main advantage of hourly instantaneous feedback is

its use in determining the energy cost of individual appliances.

29
This use of instantaneous feedback may have diminishing

returns since there is no need to continuously monitor

the energy consumption of various appliances once this

information has been learned.

The problem participants had with instantaneous feedback

is that it is not based on actual use of energy and as

an estimate has limited information value. It is recommended

that a careful analysis be performed regarding the appropriateness of providing instantaneous feedback in a feedback

meter since consumers reported some difficulty in understanding

the purpose and derivation of instantaneous feedback.

Baldwin (1977) suggests several functional characteristics

of effective feedback. First, feedback should always be

expressed in the most meaningful units possible. The

present study used feedback values expressed as dollars

and cents. All participants found this to be a meaningful

measure of energy consumption. Participants were overwhelmingly

in favor of the meter presenting gas and electric costs

as separate values. As a result it is recommended that

feedback be geared to the needs of the consumer such that

consumers receive feedback segmented into the energy sources

appropriate for their homes.

Second, Baldwin recommends that there be a clear understanding of the purposes for which feedback information

will be used by the household. Participants in the present

study indicated that they would use energy cost feedback 1 primarily for purposes of budgeting, determining energy

costs associated with given patterns of energy use, and

determining energy costs of various appliances. These

intended uses of feedback dictate that feedback should

be provided in a form that allows monitoring and comparison

of actual energy use. The usefulness of cumulative feedback

for budgetary purposes as well as for determining energy

costs associated with given patterns of energy use combines

two desirable features of feedback. For determining energy

costs of various appliances, some participants suggested

an appliance metering device that could be connected to

one appliance at a time. Such a device would be preferable

to any form of feedback presented in the present study

for this purpose.

Third, Baldwin suggested that feedback should allow

comparison with past performance. Cumulative feedback

allows these comparisons to be made; however, the consumer

is generally required to keep records to facilitate this

process. If the final cumulative daily feedback value

is saved for 24 hours, then a simple inspection of the

30
display will allow comparisons between the current daily

cumulation and that of the previous day. The use of instantaneous feedback for comparison purposes is somewhat obscure

to participants due to its constantly changing values.

Seligman notes that feedback should be given in a

form that is most meaningful to the homeowner. Cumulative

feedback appeared to be the most understandable form of

feedback in terms of its purpose and derivation. Participants

reported some confusion over the purposes and derivation

of projected and instantaneous feedback. Participants

questioned the credibility of these latter feedback types

since the values displayed are estimates which make what

they consider to be some unrealistic assumptions about

behavior and energy use . For example , hourly instantaneous

feedback provides an estimate of energy cost that assumes

that you continue to use energy at the same rate for an

hour; projected daily feedback assumes that energy will

be used at the same rate tomorrow as it was today. Given

participants' reactions, instantaneous and projected feedback

are not recommended as forms of energy feedback for consumer

use. If care is taken to insure adequate education about

the meaning and use of these forms of feedback, some of

the problems in meaningfulness and understandability may

be alleviated. The question still remains whether instantaneous and projected feedback are suited for the uses

which consumers will make of energy cost feedback information.

Seligman has also said that feedback should be nonabrupt

in showing changes from one presentation to another. Instantaneous feedback does not meet this criterion because the

values displayed are subject to momentary variations in

energy usage, thus affecting cost estimates from moment

to moment. Projected feedback may also show abrupt changes

in energy cost estimates from day to day since projected

feedback is always based on the previous day's energy cost.

There may be ways to avoid the abruptness problem by averaging

feedback over several days or by eliminating quantitative

feedback in favor of some simpler reinforcing signal system.

In summary, it is recommended that a feedback meter

incorporate a daily cumulative feedback display, the final

total of which can be saved for the next 24 hours on a

separate display. This would allow the user to monitor

energy use of individual appliances as well as patterns

of appliance use. Second, a monthly cumulative feedback

figure should be provided since consumers found it useful

for budgetary purposes. Any additional energy cost information

31
could be easily supplied by educational materials rather

than by an hourly instantaneous feedback display. Since

the use of an hourly instantaneous feedback display for

monitoring energy consumption of individual appliances

was expected to be of only short term value by the participants, the third recommendation is that careful consideration

be given to including hourly instantaneous feedback as

a part of energy cost feedback meters. All energy cost

figures should be displayed as separate energy costs (e.g.

gas and electric) where applicable to facilitate consumer

use of energy cost information.

Future Research Areas

Becker and Seligman (in press) cite data suggesting

that feedback does not necessarily need to be quantitative.

In that study, a blue flashing light was used to signal

air-conditioner operation when the outside temperature

was below 68°F. Results indicated that the blue light

alone was sufficient to cause a reduction in energy consumption. An empirical field study should be conducted to

further investigate the effectiveness of nonquantitative

feedback

.

Participants in the present study indicated that their

use of hourly instantaneous feedback may be short-lived.

The effects over time of the various types of energy-cost

feedback need to be studied in order to develop feedback

meters capable of maintaining reduced energy consumption

and at the same time incorporating a cost-effective design.

>

Another avenue of future research involves investigating

individual versus group feedback. Baldwin (1977) has

suggested that comparing consumer's energy consumption

to a group norm may have a motivating effect on conservation

"keeping up with the Joneses." Further work in this area

will help clarify the relative effectiveness of individual

and group feedback.

As a laboratory-based study, the present study did

not allow a statistical evaluation of the effectiveness

of the various types of feedback. The effectiveness of

feedback is best tested using field study techniques.

Appendix L contains a proposal for such a field study,

designed to determine the effectiveness of the feedback

types investigated in the present study.

If the effectiveness of a particular type of feedback

is verified, its application to other types of conservation

should be investigated. An example of an area in which

feedback may prove beneficial is in water conservation.

32
Another possible use of energy feedback involves

installing a device which displays a cost value for energy

use of individual appliances. This would allow the consumer

to see the cost of using a single appliance at a time.

The value of providing such feedback for individual appliances

may be tested to determine the effect of such information

on energy conservation efforts and appliance use.

Only a few possible research areas have been mentioned

here. As more data is obtained on the effects of feedback

on conservation behavior, it will become desirable for

these data to be assimilated and a general theory of

conservation/consumption feedback developed. Such a theory

could facilitate the use of these data in reducing consumption

of other limited resources.

33
References

Baldwin , F.D. Meters , bills, and the bathroom scale.

Public Utilities Fortnightly , February 3, 1977.

Becker, L.J. and Seligman, C. Reducing air-conditioning

waste by signalling it is cool outside. Personality and

Social Psychology Bulletin , in press.

PEPCO Study, personal communication with L. Collins,

Chief, Consumer Motivation Branch at the U.S. Department

of Energy, January 1978.

Seligman, C. Why does feedback facilitate residential

energy conservation? Paper presented at the 1978 Annual

Meeting of the Human Factors Society , Detroit, Michigan.

October 16-19, 1978.

Seligman, C., Darley, J.M. and Becker, L.J. Psychological

strategies to reduce energy consumption: First annual

progress report. Center for Environmental Studies Report

No. 41 , Princeton, N.J., November, 1976.

Winett, R. A .

,

Kaiser, S. and Haberkorn, G. The effects of

monetary rebates and daily feedback on electricity

conservation. Journal of Environmental Systems , in press.

Winett, R. A .

,

Neale, M. , Williams, K. , Yokley, J. and

Kauder, H. Preliminary report on the use of feedback

to promote residential electricity conservation. Institute

for Behavioral Research, Inc. . Silver Spring, Maryland,

Summer, 1977.

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35
Appendix A

Table 2

Appliance Energy Cost Values Displayed for Instantaneous Feedback

Estimated Cost

(Both Winter and Summer Scenarios)

Appliances/Home Type** Time Periods

Hourly Daily Monthly

Gas Range/G&E $0.18 (13) *** $ 4.32 $ 129.60

Electric Range/E 0.61 (ID 14.64 439.20

Gas Water Heater/G&E 0.62 (13) 14.88 446.40

Electric Water Heater/E 0.12 (11) 2.88 86.40

Gas Clothes Dryer/G&E 0.08 (13) 1.92 57.60

Electric Clothes Dryer/E 0.24 (ID 5.76 172.80

Electric Refrigerator/G&E/E 0.02 (14) 0.48 14.40

Electric Freezer/G&E/E 0.02 (14) 0.48 14.40

Electric Dishwasher/G&E/E

Electric Clothes

0.06 (ID 1.44 43.20

Washer/G&E/E 0.03 (ID 0.72 21.60

Gas Heating System/G&E 0.83 (13) 19.92 597.60

Electric Heating System/E

Electric Air Conditioner

1.00 (12) 24.00 720.00

G&E/E 0.20 (12) 4.80 144.00

Winter Gas Total/G&E 1.71 41.04 1231.20

Summer Gas Total/G&E .88 21.12 633.60

Winter Electric Total/G&E 0.13 3.12 93.60

Summer Electric Total/G&E 0.33 7.92 237.60

Winter Combined Total/G&E 1.84 44.16 1324.80

Summer Combined Total/G&E 2.04 48.96 1468.80

Winter Electric Total/E 2.10 50.40 1512.00

Summer Electric Total/E 2.30 55.20 1656.00

* Daily and weekly cumulative costs were derived from national

average daily energy consumption data. Monthly cumulative

costs were derived from average dailv energy consumption data

of cities whose weather approximates that of Washington , D.C.

** Home type refers to the "gas and electric home" scenario (G&E)

and "all-electric home" scenario (E)

.

"G&E/E" indicates that

the appliance is included in both home types.

*** Numbers in parentheses are reference numbers for literature

sources listed in Appendix A, Table 4.

36
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parentheses

are

reference

numbers

for

literature

sources

listed

in

Appendix

A,

Table
Appendix A

Table 4

Literature Sources for Energy Cost Estimates

Reference

Number Source

1

2

3

4

5

6

7

8

9

10

Patterns of Energy Use by Electrical Appliances

Study , Midwest Research Institute, Final report to

U.S. Department of Energy, January 1978, Table D-3,

"Average Daily Electric Consumption by Appliance,

City and Month", January Electric Consumption,

Philadelphia, Pa.

Ibid, Table D-3, August Electric Consumption,

Philadelphia, Pa.

Ibid, Table D-3, January Electric Consumption,

St. Louis, Mo.

Ibid, Table D-3, August Electric Consumption,

St. Louis , Mo

.

Ibid, Table D-3, January Electric Consumption,

Boston, Mass.

Ibid, Table D-3, August Electric Consumption,

Boston, Mass.

Ibid, Table 5-3, "Average Daily Electric Consumption

by Appliance Per Month", Januarv Electric Consumption

Ibid, Table 5-3, "Average Dailv Electric Consumption

bv Appliance Per Month", August Electric Consumption

Gas Facts: 1976 Data . Arlington, Va.: American

Gas Association, 1971, Table 107, January Therm

Consumption, p. 129

Ibid, Table 107, August Therm Consumption

11 Annual Energy Requirements of Electric Household

Appliances , Edison Electric Institute, EEI-Publication

#75-61 Revision

12 Sears, Roebuck and Company Catalog , 1978, (derived

approximation of average wattage ratings for electric

heating systems and electric air conditioners)

.

13 Gas Engineers Handbook: Fuel Gas Engineering

Practices , N.Y.: Industrial Press, First Edition,

Second Printing, 1966. Table 9-24, p.9/63

14 The U.S. Fact Book; The American Almanac , N.Y.

Grosset & Dunlap, 1976, Table 891, p. 537.

38
APPENDIX B

Energy Usage Questionnaire

1. Do you use electricity Yes No

a. for lighting, cooking, and other

appliances /~7 /~7

b. for air conditioning? /~~7 / /

c. for hot water? /~~7

/~~7

d. for heating your home? /~~7

/~7

2. Do you use natural gas

a. for cooking or other appliances? /~7 /~~7

b. for air conditioning? / / / /

c. for hot water? / / / /

d. for heating your home? /~~7 /~7

3. Do you use fuel oil

a. for hot water? /~7 / /

b. for heating your home? / / / /

4

.

What portion of your monthly income do you spend for energy

(including gas, electricity, fuel oil, etc.) in the winter?

For example, 1/3, 1/2, 1/4, etc.

5.

What portion of your monthly income do you spend for energy

(including gas, electricity, fuel oil, etc.) in the summer?

For example, 1/3, 1/2, 1/4, etc.

6.

Do you know how the utility companies charge you for your

energy usage? How?

7.

Do you know how much you are charged per kilowatt hour

(for electricity) and per therm (for gas)? How much?

8.

Do you think people should conserve energy usage in their

homes whenever possible? Why?

39
9

.

Do you try to conserve energy in your home?

10. If you said yes, why do you conserve energy in your home?

If you said no, why don't you conserve energy in your home?

11. What do you do in your home to conserve energy?

12. Do you regularly check your electricity meter?

13. What other things could you do to conserve energy in

your home?

14. Do you now know how much energy you are using?

15. Do you

energy

think you have great daily variations in your

usage?

16 . Do you think that if you had more information about energy

use that it would help you reduce your own use of energy?

17. What kind of information do you need to help you use

energy more efficiently in your home?

18. If you had this extra information how would you use it?

40
19.

Do you think it would help you to have more information

about how much energy the different appliances in your

home use?

20.

21. If you had this information, how would you use it?

What could the utility companies do to help you conserve

energy and reduce your energy usage?

41

APPENDIX C

Feedback Explanation

The purpose of this study is to evaluate energy cost

feedback. What is energy cost feedback? Basically , it

tells you how much the energy you are using is costing you.

There are numerous ways in which energy cost information

can be presented. The one you are perhaps most familiar

with is your monthly utility bill. Another way to show

energy cost information is to place a meter directly in the

home. The meter then would have one or more displays

showing the cost of your energy usage.

The role you will be playing in this study will be to

tell us what energy cost information you feel would help

you most as a consumer. We are assuming that most consumers

want to conserve energy, if for no other reason than to save

money. We will be showing you a number of different types

of energy cost displays. Then we'll ask you for your

reactions to them. Do you have any questions so far about

energy cost feedback?

I'll spend a few minutes now describing the kinds of

feedback displays you'll be looking at. First, there are

three main ways in which energy cost can be presented.

These are, first, by cumulating or adding up the cost of

the energy you have used so far; second, by sampling the

energy that you are presently using and providing instantaneous or immediate feedback about your current energy

usage; and, third, by projecting previous energy usage to

some future time period. Let's talk about cumulated feedback first.

Cumulative energy cost feedback adds up the cost of

the energy you have used so far. Energy costs can be

accumulated for a day, a week, or a month. For example,

you would be able to see your energy costs adding up throughout the day until at the end of the day you would be able

to look at the display and see how much your energy usage

had cost for that day. Then, the display would reset and

the next day's accumulation would begin. If your energy

cost was cumulated for a week, you could see the display

adding up your energy cost until at the end of the week

you would be able to look at the display and see how much

your energy usage had cost for that week. Then the display

would reset, and the next week's cumulation would begin.

Energy costs accumulated for one month would work the same

way, so that at the end of the month you would be able to

see how much your energy usage had cost you for the whole

month. As with the other displays, the energy cost information would be reset for the next month's cumulation.

43
The second main kind of energy cost information provides

instantaneous energy costs. What this basically means is

that the feedback meter in the home would periodically sample

how much energy is currently being used. The display would

then be telling you that "if you continue to use energy at

the rate you used it for, let's say, the last ten seconds,

your cost at the end of the hour, day, or month would be so

much money. Let's look at an hourly instantaneous estimate

as an example. If you have a certain number of appliances

on at once, the feedback meter would tell you that if you

continue to run these appliances for one full hour, your

energy cost would be $2.48 for that hour. The values displayed for instantaneous would be updated every ten seconds

or so.

The main difference between cumulated and instantaneous

energy cost feedback is that cumulated feedback tells you

the cost of the energy you have actually used so far;

whereas instantaneous feedback tells you what your energy

cost would be if you continued to use energy at the rate you

are now using it.

These two concepts may seem somewhat confusing to you.

I'd like you to take a few minutes to tell me in your own

words what instantaneous feedback is and what cumulative

feedback is.

The third type of energy cost feedback is projected

feedback. Projected feedback is based on the previous

day's energy cost. That is, if yesterday's energy cost was

$5.00, the projected weekly value would be $35 or $5.00 x seven

days. The projected monthly value would be $150 or $5.00

x 30 days. Of course, the projected daily value would be

the same as yesterday's cost since it is equal to yesterday's cost times one. Projected feedback tells you what

your energy usage will cost if you continue to use energy

at the same rate as yesterday. The values displayed for

projected feedback would change each day based on the energy

cost of the previous day.

I'd like you to take a few minutes to tell me in your

own words what projected energy cost feedback is.

The difference then between projected energy cost feedback

and cumulative feedback is that projected feedback tells you

what your daily, weekly or monthly energy costs would be if

you continued to use energy as you had yesterday; whereas,

cumulative feedback tells you the cost of the energy you have

actually used so far that day, week or month.

44
The difference between projected energy cost feedback and

instantaneous feedback is that projected feedback is based on

yesterday's energy cost, while instantaneous feedback tells

you what your energy cost would be for an hour, day or month

if you continued to use energy at the rate you are presently

using it.

Now please describe in your own words what the differences

are between instantaneous, projected and cumulative feedback.

So far we have talked about what energy cost feedback is

in general and about three main kinds of feedback, that is,

cumulative, instantaneous, projected feedback. The next thing

that you will need to know about energy cost information is

that your energy cost can be broken down into its major components. In this study, we will be talking about gas and

electric costs as the two major components of total energy

cost. So in addition to having a total energy cost value,

you could have an electric cost value and a gas cost value

displayed separately.

Let's quickly review what we've gone over so far. 1)

cumulative energy cost feedback adds up the cost of your

energy usage so far. Cumulation time periods are daily,

weekly or monthly. 2) For instantaneous energy cost feedback,

your energy usage rate would be periodically sampled (let's

say every ten seconds) . The display would then tell you

what your energy cost would be if you continued to use

energy at that rate for a certain time period. Instantaneous

time periods are hourly, daily or monthly. 3) Projected

energy cost feedback tells you what your energy usage will

cost if you continue to use energy at the same rate as

yesterday. The time periods associated with projected

feedback are daily, weekly and monthly. 4) For all three

types of energy feedback, energy cost can be presented as a

total or be broken down into gas and electric.

Do you have any questions now?

45
•

'
APPENDIX D

Equipment Explanation

The equipment used for this study has four basic

components: 1) a computer which will produce the displayed

energy cost values? 2) a feedback meter that can display as

few as one or as many as six different values at one time;

3) a terminal which will allow you to simulate appliance

usage by either turning on or off appliances, thus allowing

you to see the changing values on the display, and which

will print out questions for you to answer and remind you

which appliances are on and which are off; and 4) a tape

recorder into which you will talk as you go through the

session allowing you to make comments or suggestions while

they are fresh in your mind.

The values you will see on the feedback meters are for

eight major appliances. The energy cost values you will see

are based on average usage of the appliances and are not

intended to represent your actual usage of these appliances.

Because you may not use appliances as they are shown here

and because other energy users within the home are not

included, the energy cost values you see displayed will

not represent your utility bill.

The type of appliances that you would have in your

home depend upon whether you have an all electric home or

a gas and electric home. (If participant has a gas and

electric or oil and electric home, read:) So we will show

your energy costs as a total as well as gas and electric

costs separately. (If participant has an all electric

home, read:) Since you have an all electric home, we will

show your cost for electricity only.

Another factor that would determine what appliances

would be on at any given time is the season of the year.

For example, you don't run the air conditioner in the

winter and the heater in the summer. So we will present

values on the displays that are based on summer appliance

usage or winter appliance usage.

47
.

.

.

•

'
APPENDIX E

Cumulative Feedback Interview Guide

1.

2. What information does cumulative daily feedback give you?

How can cumulative daily energy cost feedback be used?

3.

What information does cumulative weekly feedback give you?

4

How can cumulative weekly energy cost feedback be used?

5.

What information does cumulative monthly feedback give you?

6.

How can cumulative monthly energy cost feedback be used?

7.

Which time period (day, week, month) do you prefer for

cumulative energy cost feedback? Why?

8

At what time of the day would you want the daily cumulative display to clear and start the next day's cumulation?

9.

Do you think that your daily cumulative meter reading

should be saved? That is , would you want to be able to

see what yesterday's meter reading was? Why?

10.

What did you find confusing about cumulative feedback?

11.

Should cumulative energy cost information be provided

separately for gas and electricity or as a total? Why?

49
. .
APPENDIX F

Instantaneous Feedback Interview Guide 1.

What information does instantaneous hourly feedback give

2. you?

How can instantaneous hourly energy cost feedback be used?

3.

What information does instantaneous daily feedback give

you?

4.

How can instantaneous daily energy cost feedback be used?

5.

What information does instantaneous monthly feedback

give you?

6.

How can instantaneous monthly energy cost feedback

be used?

7.

Which time period (hour, week, month) do you prefer for

instantaneous energy cost feedback? Why?

8.

What amount of time should be sampled to provide an

instantaneous estimate of energy cost?

9.

What did you find confusing about instantaneous feedback?

10.

What do you like/dislike about an instantaneous energy

cost estimate?

11.

Should instantaneous energy cost information be

provided separately for gas and electricity or as a

total? Why?

51
.
APPENDIX G

Projected Feedback Interview Guide

1.

2. What information does projected daily feedback give you?

How can projected daily energy cost feedback be used?

3.

What information does projected weekly feedback give you?

4.

How can projected weekly energy cost feedback be used?

5.

What information does projected monthly feedback give

you?

6.

How can projected monthly energy cost feedback be used?

7.

Which time period (day, week, month) do you prefer for

projected energy cost feedback? Why?

8.

What did you find confusing about projected feedback?

9.

What do you like/dislike about a projected energy

cost estimate?

10.

Should projected energy cost information be provided

separately for gas and electricity or as a total? Why?

11.

Should projected energy cost information be based on

yesterday's cumulative value or some other time period?

53
'
APPENDIX H

Meter Design Interview Guide

"This chart shows all the possible types of feedback

we have examined. Think about them and decide which one(s)

you would personally like to use to design your own feedback

meter. You can have any combination of projected, cumulative

and instantaneous feedback and may use as many or as few

displays as you think you would really use.

As you select the information you want, we will display

the information for you so you can see how it would work.

Feel free to change your mind at any time."

For each display chosen, ask:

Why did you pick feedback?

How would you use this information?

Why did you choose this particular combination of displays?

Is there any other information you would like displayed?

55
(If more than three displays chosen, ask subject to limit

choices to three)

Why did you choose this particular combination of displays?

56
APPENDIX I

DOE Prototype Meter Interview Guide

Enter this combination:

cumulative daily

cumulative monthly

cumulative hourly

Suppose I were to design this energy feedback meter.

What do you think of this sample feedback meter?

How could you use this information?

What do you like about this particular combination?

What do you dislike about this particular combination?

What time of the day should the daily cumulative display

clear and start the next day's cumulation? Why?

Should your previous day ' s energy cost be stored on a

separate display?

57
’
APPENDIX J

Final Interview

1.

Which kind of energy cost feedback is most meaningful or

helpful for you? Why?

2.

How many kinds of information should an energy cost

feedback meter provide to the consumer?

3.

How does cumulative daily energy cost feedback differ

from projected daily energy cost?

4.

How does instantaneous energy cost differ from projected

energy cost?

5.

How does cumulative energy cost differ from instantaneous

energy cost?

6.

What do you like/dislike about cumulative energy cost

information?

7.

What do you like/dislike about instantaneous energy

cost information?

8.

What do you like/dislike about projected energy cost

information?

9

What is not clear about how to use energy cost information?

10.

What additional information should be displayed on an

energy cost feedback meter?

59
11.

Do you think information about your energy cost would be

helpful to you in saving energy in your home? How would

you use this information?

12.

What did you find confusing about cumulative feedback? 13.

What did you find confusing about projected feedback? 14.

What did you find confusing about instantaneous feedback?

15.

Given the cost of your energy today, do you think you

would buy and use an energy feedback meter? Why?

16.

How expensive would energy have to become before you

would buy and use an energy feedback meter? Why?

17.

What kinds of instructional materials should accompany

an energy cost feedback meter?

For instance —what kind of information should be provided

a. for how to read your meter?

b. for what the numbers mean and how they could

be used?

c. for what each display on the meter represents

and how they could be used?

d. about the cumulative display and how it resets

at the end of a certain time period?

e. about appliance energy consumption?

f . about how to conserve energy?

60
g. about money saved by using various thermostat

settings?

h. about the difference between meter reading and

actual energy bills?

61

APPENDIX K

Human Factors Considerations for

Energy Feedback Meters

Introduction

A system designed for ease of operation inspires

confidence and increases efficiency. In a time of increasing energy demand and dwindling fuel supplies it would be a

disservice to the consumer to develop a potential energy

saving device that did not attend to the capabilities and

limitations of the user. The consideration of the human

element has been proven to be a significant factor in

maximizing human performance reliability (DeGreene 1970) , thereby contributing to the overall success of the system.

The interface between the energy feedback meter and

the individual is relatively simple. Attention on the

part of the manufacturer to a few specific recommendations

in some cases and consideration of minimum requirements in

others will insure an optimal man-machine interaction.

Three specific areas are addressed: display construction,

the labeling of the feedback meter and the placement of the

meters

Display Construction

Safety considerations dictate that the size of the

unit should not extend beyond 6.35 cm from the wall

(McCormick 1970) . In addition, the unit should not exceed

30.48 cm in height and the width should be approximately

80 percent of the height.

Visual displays should be arranged so as to minimize

eye movements and present important information in easilyseen locations. Rules for the arrangement of visual displays

(Van Cott 1972, McCormick 1970) include:

o Placement of the displays in front of the operator,

as nearly perpendicular to the individual's line

of sight as possible,

o All the displays necessary to support the feedback

process should be grouped together,

o When multiple displays are grouped together, the

displays should have brightness uniformity.

63
o A minimum height of 1.02 cm is sufficient to

enhance the readability of the numeric figures

at a distance of 152.4 cm, well beyond the

optimal viewing distance of 71.12 cm,

o The displays should be mounted as close as

possible to the panel surface so as to minimize

parallax and maximize viewing angle.

o Transilluminated light emitting diodes (LED) and

liquid crystal diodes, can be purchased off the

shelf to meet or exceed the minimum recommended

size of the numeric characters (AFSC 1970)

.

o Transilluminated displays should be constructed,

arranged and mounted to prevent reduction of

information transfer due to the reflection of

ambient illumination from the display (AFSC 1970)

.

o The luminance contrast within the indicator

should be at least 50 percent under normal

operating conditions. Since the displays are

likely to be used under varied ambient illuminance, a dimming control should permit the

displays to be legible under all expected

ambient illuminance (AFSC 1970)

.

Labeling

The labeling of the energy feedback meters can have a

significant effect on the individual's ability to utilize the

device (AFSC 1970) . Below is a set of guidelines (AFSC 1970)

which will assist the manufacturer in optimizing the effectiveness of these labels:

o Label the indicators in terms of what is being

measured, not by the name of the device.

o Label the indicators in the most simple and direct

manner possible.

o Make the labels as brief as possible, but do

not use abreviations , unless they are familiar

to all the expected consumers.

o Position the labels so that numerical designations

are not crowded or obstructed, and

64
o Do not include company names or trade names on

the usable portion of the display.

o Capital letters ("all caps") are recommended.

The recommended size of the alphanumeric

characters should have a width height ratio of

3:5, except for the "1" which should be one

stroke width wide. The stroke width should be

1/6 to 1.8 of the height (Van Cott 1972).

Location

Displays should be located and designed so that they

may be read accurately in the normal standing position

(McCormick 1970, Van Cott 1972). The normal line of sight

of individuals is about 15° below the horizon (Haber and

Hershenson 1973) . Limited eye and head movements permit

a fairly convenient visual scanning of an area roughly 15°

around the normal line of sight—up and down and sideways.

This area defines the approximate optimum location for

visual displays. However, the neighborhood areas are also

reasonably satisfactory for visual displays, such as the

angle from the horizontal down to about 35° to 45° and a

total lateral range of about 45° to 60° from a straight

ahead direction.

Summary

It is not the intent of this section to present

inflexible specifications from which the feedback meter

should be developed and it is not requisite that the

recommendations be followed stringently. Rather they

serve to provide a simple mechanism for considering the

human performance capability within the framework of the

energy feedback meter.

References

Air Force Systems Command Design Handbook Series 1-3,

Human Factors Engineering, 1 December 1970. WriqhtPatterson AFB OH 45433.

DeGreene, K.B. Systems Psychology , McGraw Hill, Inc.

New York, 1970.

Haber, R.N. and Hershenson, M. The Psychology of Visual

Perception. Holt Rinehart and Winston, Inc. New York,

1973.

65
McCormick, E.J. Human Factors Engineering (3rd ed)

McGraw Hill Book Company, New York, 1970.

Van Cott, H.P. and Kinkade , R.G. (ed) Human Engineering

Guide to Equipment Design (Rev. Ed.) McGraw Hill Company,

New York, 1972.

66
APPENDIX L

A Proposal for Field Testing

Energy-Cost Feedback Meters

Background

A research effort resulting in human factors recommendations

for performance characteristics of energy-cost feedback

devices was conducted by the Consumer Ergonomics and Information Group at the National Bureau of Standards. This effort

supported the work being done by DOE's Consumer Motivation

Branch (CMB) in the area of energy-cost feedback. Interviewing techniques were used to provide consumer reaction

to various types of energy-cost feedback. The issues

addressed included: consumer motivation to use energy feedback meters; meariingfulness and usability of various types

of feedback; preferences among the various feedback types;

and, educational or instructional materials to accompany

feedback meters.

Since information collected on the above issues was not

based on actual usage of energy-cost feedback meters by

consumers in their homes, recommendations made to DOE's

Consumer Motivation Branch should be evaluated in the field.

CMB now plans to conduct a field demonstration project to

illustrate to manufacturers, utilities, and consumers the

usefulness of energy feedback meters in reducing residential

energy consumption by providing only one fixed meter design.

It is the objective of this proposal to demonstrate the

feasibility of performing a more detailed field evaluation

of various meter designs without significantly increasing

the cost over that of the demonstration project.

Proposed Study

It is proposed that a field experiment be conducted rather

than simply a demonstration project. Through a field study

it would be possible not only to demonstrate the usefulness

of residential energy-cost feedback, but it would make field

testing the efficacy of several types of energy feedback

meters possible.

The energy-cost feedback meter that DOE is considering for

use in its demonstration project incorporates three types

of information. These are: a) daily cumulative feedback

(DCF) —constantly monitors energy usage and displays a

cumulation of the cost of energy consumption for a 24 -hour

period, b) monthly cumulative feedback (MCF) —constantly

monitors energy usage and displays a running cumulation of

the cost of energy consumption for a monthly period, and

67
c) hourly instantaneous feedback ( II IF ) —monitors current energy

usage and estimates what the cost would be if consumption

continued at that rate for one hour. The device samples energy

use and updates the display every 15 seconds. A fourth type

of energy-cost information that will be\ presented is yesterday's

daily cumulative feedback total figure (YDCF) . According to

DOE's plan, DCF will be constantly displayed on the feedback

meter. When the consumer wishes to view any of the remaining

three types of information (flCF , HIF , or YDCF) the consumer

would push a button, causing the desired information to be

temporarily displayed.

The field study design being proposed by NBS would allow the

consumer an opportunity to use various combinations of the

above-mentioned feedback types. The difference between DOE's

meter design and that proposed by NBS is that the NBS meter design

would contain a switch that is not accessible by the participant and which would be set by field personnel to activate the'

particular feedback combination to which participants will be

exposed. As with the DOE plan, the energy-cost feedback meter

utilized in the proposed study will include one type of energy

feedback displayed constantly and others that will be displayed

when the consumer/participant engages a push-button. So,

participants in the field study would be provided with an

energy cost feedback meter containing one constant display that

can be momentarily changed by the consumer to display one of

three other types of feedback. The YDCF display need not be

included in the field experiment as an independent variable

since this display is a convenience feature only and would

not foreseeably be used differently than DCF for controlling

energy consumption. However, all experimental participants

will be allowed to push a button to have this figure displayed.

Experimental Design

The four experimental conditions which will be employed are

illustrated in Table 1. In condition A, the DOE feedback

meter participants will use a feedback device in which daily

cumulative feedback is displayed constantly, while hourly

instantaneous feedback and monthly cumulative feedback will

be displayed when the participant engages a push-button.

In condition B, hourly instantaneous feedback will be constantly displayed, and daily cumulative feedback and monthly

cumulative feedback can be displayed by pushing a button.

Cumulative monthly feedback is displayed constantly in

condition C, with hourly instantaneous feedback and daily

cumulative feedback being displayed when a button is pushed.

In condition D, preference data will be collected by allowing the participants to choose whether they prefer to see

either condition A, B, or C again for the final quarter.

68
Table 1

Four Experimental Conditions

Condition

Constant

Display

Optional

Displays

A DCF MCF, HIF, YDCF

B HIF DCF, MCF, YDCF

C MCF DCF, HIF, YDCF

D Participcant's Preference

69
The design of the proposed field study is illustrated in

Table 2. It is proposed that a minimum sample size of 500

be incorporated, with 100 participants being assigned to each

of the five matched groups distributed equally across the

demonstration areas. Presentation of the feedback conditions

A , B, and C will be counterbalanced.

Participants in Group 1 will remain in condition A for one

full year. Group 2 will be in condition A for three months,

then condition B for three months, followed by condition C

for three months. Group 3 will view feedback meters with

condition B presented in the first quarter, condition C in

the second, and condition A in the third. Group 4 will first

be exposed to condition C, then condition A, and then condition B. Participants in groups 2, 3 and 4 will choose

their preferred condition for use during the final quarter,

condition D. Group 5 is the control group and will receive

no energy cost feedback.

Experimental Measures

All groups will be constructed so as to insure that they

are matched in terms of energy consumption prior to installation of the energy-cost feedback meters. At the end of

each three-month period, energy consumption readings will

be made at each household in the experimental groups (groups

1 through 4) and the control group (group 5)

.

Comparisons of energy consumption will be made to determine

the effects of the conditions and orders. Those comparisons

are illustrated in Table 3. It can be seen that a great

deal of data can be gathered by conducting an experimental

field study as opposed to a simple demonstration project.

If a demonstration project alone was conducted, only

comparisons 1 and 5 could be made.

At the end of each quarter, measures will also be taken

of the frequency with which participants select each of

the two available optional displays. In this connection,

"optional displays" refer to the two feedback types that

are accessible by pushing buttons on the feedback meters.

Frequency data will be analyzed using an analysis of variance

to determine whether any preferences are shown in optional

feedback types accessed.

In addition to taking readings of energy consumption and

feedback selection frequencies for each quarter, written

or oral questionnaires will be administered to the participants, In this way, insights can be gained to determine

subjective reactions to the various types of energy-cost,

feedback meters. Without compromising the intent of the

demonstration project and at minimum additional cost, a

more detailed evaluation of device effectiveness can be

'conducted.

70
Table 2

>

12 Month Test Period

Test Groups 1st

3 Months

2nd

3 Months

3rd

3 Months

4 th

3 Months

1 A A A A

2 A B C D

3 B C A D

4 C A B D

5 Con :rol Condit: ion - no fe<sdback

71

USCOMM-DC
Table 3

Comparison

Between Groups

1. Group 1 to Group 5

Quarters 1 thru 4 individually and annual total

2. Groups (2 , 3, and 4) to

Group 5

Quarters 1 thru 3 individually and annual total

3. Group 1 to Groups ( 2 , 3,

and 4)

Final Quarter

4 . Group 2 to Group 3

Group 2 to Group 4

Group 3 to Group 1

Quarters 1 thru 3 totals

Within Groups *

5. Group 1

Compare each Quarter to

each other Quarter

6. Across Groups 2 , 3, and 4

compare Condition A to

Condition B to Condition C

Purpose

Describe differences in energy consumption between Experimental Condition A and the Control Condition

Describe differences in energy consumption between the counterbalanced presentation of experimental Conditions A, B, and C and

the Control Condition

Describe differences in energy consumption between a forced choice'

(Condition A) and a preferred

choice (Condition D)

Describe any order effects

Describe the effects on energy consumption of the Condition A device

over time

Describe the main effects of treatment conditions (are there

differences in energy consumption

between Condition A, Condition B,

and Condition C)

72
NBS-114A (REV. #-76) *,6ovh.*^WMM&n NoJ 1 Iteclfjfent's Accession No.

!-V: . '

; \ F*' .

U.S. DEPT. OF COMM.

BIBLIOGRAPHIC DATA

SHEET

1. PUBLICATION OR REPORT NO. NBSIR 79-1771 zm. • 4. TITLE AND SUBTITLE

An Investigation of Preferences for Various Types

of Energy Cost Feedback

5. Publication Date August 1979

----- • 7. AUTHOR(S)

Ann Ramey-Smith and Jennifer L. Gagnon

8. Performing Organ. Report No.

9. PERFORMING ORGANIZATION NAME AND ADDRESS

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON, DC 20234

n)ii>iilin)i)i1i>.,i)i>.i.^iiii..iin 11. Contract/Grant No.

12. SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street, City, stste, ZIP)

U. S. Department of Energy

Consumer Motivation Branch

Washington, D.C. 20545

13. Type of Report & Period Covered Final

•••;'

15. SUPPLEMENTARY NOTES

| | Document describes a computer program; SF-185, FIPS Software Summary, is attached.

16. ABSTRACT (A 200-word or too* factual aummary of moat significant information. If document includes a significant bibliography or

literature survey, mention it here.) The present study addressed the issue of consumer preferences for

various types of energy cost feedback for individual consumers. Its

purpose was to provide human factors recommendations to DOE related to

the performance characteristics of energy cost feedback devices for use

by DOE in testing energy cost feedback meters. Simulation and interview techniques were used to provide consumer reaction to cumulative,

instantaneous, and projected feedback presented as dollar and cent

values. A majority of participants indicated a preference for cumulative feedback types. All types of cumulative feedback are easily

understood, accurate in reflecting actual energy consumption and suitable to several uses. Hourly instantaneous feedback was considered

useful for monitoring energy use of individual appliances. All participants having two energy sources in their home expressed a preference

for having feedback presented as separate cost figures rather than as

a total cost. Recommendations for feedback types as well as some

performance characteristics of energy cost feedback meters for further

testing by DOE are discussed.

17. KEY WORDS (six to twelve entries ; alphabetical order; capitalize only the first letter of the first key word unless a proper name

;

separated by semicolons)

Attitudes; consumer preference? energy? energy cost; feedback;

feedback meters

18. AVAILABILITY Jfxl Unlimited

I I For Official Distribution. Do Hot Release to NTIS

FJ Order From Sup. of Doc., U.S. Government Printing Office, Washington, DC

20402, SD Stock No. SN003-003- ^25 Order From National Technical Information Service (NTIS), Springfield, VA. 22161

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