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    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Gathering and Presenting Social Feedback to Change Domestic Electricity Consumption</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Matthew Studley and Simon Chambers</string-name>
          <email>matthew2.studley@uwe.ac.uk</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ruth Rettie and Kevin Burchell</string-name>
          <email>r.rettie@kingston.ac.uk</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Author Keywords</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Kingston University</institution>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Nudge, Social Norms</institution>
          ,
          <addr-line>Smart Meters</addr-line>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>University of the West of England</institution>
        </aff>
      </contrib-group>
      <abstract>
        <p>This paper describes the CHARM Energy Study in which mobile technology is used to study the impact of social group feedback on household energy consumption. We describe the background and rationale behind the study, the technology which supports the study, and the study's methodology. The work described herein builds upon similar studies by using mobile technology and on-line feedback to increase the frequency of accurate social group feedback to the participants.</p>
      </abstract>
    </article-meta>
  </front>
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    <sec id="sec-1">
      <title>-</title>
      <p>
        CHARM is a three-year EPSRC funded UK project that
evaluates the impact of individual and social group feedback
on behaviour in three different contexts, including
electricity consumption. The research aims to develop, evaluate
and understand the ways in which digital technology can be
used to shape individual behaviour by informing and thereby
challenging ‘normal’ practice. Social norm research
suggests that we can influence behaviour by telling people what
other people do [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ].
      </p>
      <p>Traditional approaches that try to change behaviour by
directly influencing attitudes and intentions often prove
inefCopyright (c) 2011 for the individual papers by the papers’ authors.
Copying permitted only for private and academic purposes. This volume is
published and copyrighted by the editors of PINC2011.</p>
      <p>
        PINC2011
fective [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. Rather than telling people what to do, it can
be more effective to use ‘social proof’ [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]; influencing
behaviour by showing people what others do. Studies in
several related disciplines suggest that everyday practices are
malleable, and can be ‘nudged’ in a socially desirable
direction by subtle forms of social influence [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ]. In particular,
research indicates that feedback on an individual’s level of
performance (e.g. electricity consumption) can change their
behaviour, and moreover, that this effect is enhanced if
supplemented by feedback on the performance of a relevant
social group.
      </p>
      <p>
        THEORETICAL FRAMEWORK
Writing from a sociological perspective, Shove [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ] explores
the social organization of normality and argues that patterns
of consumption are shaped by the taken-for-granted
practices of everyday life: ‘much consumption is customary,
governed by collective norms and undertaken in a world of things
and socio-technical systems that have stabilizing effects on
routines and habits’ (p. 9). Shove emphasises the
collective conventions that underlie individual conceptions of
basic needs such as cleanliness and comfort. Thus, a
yearround indoor temperature of 22 C has become an accepted
standard of comfort that shapes buildings, clothing habits
and energy consumption patterns, while daily showering has
become an accepted cleanliness practice in the UK, with
consequent impact on energy and water consumption. These
expectations are taken-for-granted, and treated as inherent
aspects of ‘comfort’ and ‘cleanliness’, but their contingency
is demonstrated by historical and global variation. Although
Shove highlights the complex socio-technical, economic,
cultural and symbolic systems that underlie conceptions of
‘normal’ practices, she argues that what people take to be
normal is not fixed but ‘immensely malleable’ (p. 199).
Consequently, she claims, it is important to understand the
‘dynamics of normalization’, that is, how do the habits and
practices of everyday life change and evolve?
Whereas Shove avoids a rational choice model with its
focus on individual choices, the relatively new field of
behavioural economics retains a focus on individual choice,
but contests the assumption of a rational economic agent,
in the light of research on the psychology of choice. Thaler
and Sunstein[
        <xref ref-type="bibr" rid="ref21">21</xref>
        ] argue that choices are inevitably influenced
by the context or ‘choice architecture’, and that it is
legitimate to deliberately ‘nudge’ people’s behaviour in order to
improve their lives. A ‘nudge’ is ‘any aspect of the choice
architecture that alters people’s behaviour in a predictable
way without forbidding any options or significantly
changing their economic incentives’ (p. 6). Thaler and Sunstein
highlight research in social psychology that shows one can
nudge people simply by telling them what other people do.
Whereas earlier research on conformity [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] relied on
overt social pressure, more recent research [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] has focused
on subtle, indirect influences of which participants may be
unaware; these are more analogous to nudges. Cialdini et
al. [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] distinguish between two types of social norms,
descriptive and injunctive. The former simply state what most
people actually do, the latter express an overtly normative
message about what people should do. Both can be effective,
but descriptive norms are less invasive. Social norm research
typically [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] includes descriptive social norms, e.g. ‘70%
of students on this campus do not take drugs’, and has been
widely used in social-norm marketing campaigns aimed at
alcohol and substance abuse among young people. Research
suggests that the impact of social norms depends on the
extent to which they are focal (i.e. salient) and in alignment
[
        <xref ref-type="bibr" rid="ref7">7</xref>
        ].
      </p>
      <p>
        Two field studies are directly relevant to electricity efficiency.
In these studies participants’ electricity meters were read by
research assistants who provided feedback on door-hangers.
Nolan et al. [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ] tested descriptive social norms such as:
      </p>
      <p>
        In a recent survey of households in your
community, researchers at Cal State San Marcos found that
77% of San Marcos residents often use fans instead of
air conditioning to keep cool in the summer. Using fans
on energy instead of air conditioning — Your
Community’s Popular Choice!
The study found that these had significantly more effect on
consumption than injunctive appeals to self interest,
protection of the environment or social responsibility, although
respondents in an earlier study (reported in the same
paper) thought that the descriptive norm message would be
least motivational. A study using a similar methodology
by Schultz et al., [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ] again used door-hangers, giving
participants feedback on their individual and local
neighbourhood electricity usage figures. This research compared a
feedback only condition (descriptive social norm) with an
intervention than combined feedback with a positive or
negative emoticon or ‘smiley’ (descriptive and injunctive social
norms). In the feedback only condition, participants who
were using more than their neighbours used significantly
less after the intervention, but those who were using less
moved towards the norm, and started to use more
electricity (the ‘boomerang’ effect). In the second condition, when
descriptive and injunctive social norms were combined, the
‘destructive’ movement towards the norm was avoided:
usage of those below the norm remained stable while the usage
of those above declined. Note, these two studies used
personal meters readers attached handwritten feedback to
respondents’ front doors; this personal element may have
enhanced the normative effect of the communication. A large
scale year long trial conducted by Cialdini at Positive Energy
(O Power) combines descriptive and injunctive social norms
in energy bills, with promising results [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
      <p>
        The study by Schultz et al. combined individual and
social group feedback, but did not distinguish between the
impacts of these two interventions. There is considerable
research on the impact of individual feedback in energy
efficiency. Darby [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] identifies feedback as the single most
promising method for reducing household energy
consumption, and calls for more field testing. Research shows that
more frequent feedback is more effective, and that feedback
can be effectively conveyed through a website [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Research
on social group feedback in energy bills is more
equivocal. Surveys conducted in the US and Norway indicate that
consumers are receptive to comparisons of their energy
consumption with relevant social groups, but Roberts et al. found
the idea of social comparison was unpopular in UK focus
group research [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. Iyer [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] reviews different expressions
and formats of comparative social feedback and advocates
small comparison groups preferably based on physical
location.
      </p>
      <p>Methodology
We performed two pilot tests, the former involving ten
participants recruited from University staff, the latter twenty
participants recruited from two coherent geographical areas
chosen to represent different socio-economic groups. Due
to the small size of the pilots no statistically valid
inferences can be drawn from their output; these trials were
performed to test technology, recruitment and communications.
The main study includes four hundred and twenty
participants professionally recruited in these two target areas.
Participants are paid an incentive for their participation.
Recruiters administered a pre-trial questionnaire (e.g.
ascertaining house type, the number of rooms in the house,
heating type, et c..). A matching questionnaire will be
administered after the trial to see what change has taken place in
the way the participants see themselves and their behaviour.
We believe that the CHARM Energy Study is unique in
using mobile technology to study the effect of frequent
online social feedback in a UK study large enough to enable
statistically-valid conclusions to be drawn.</p>
      <p>Households were randomly assigned to one of three
conditions; control (no feedback), individual feedback only, or
both individual and social group feedback. The control groups
have their energy use monitored but receive no
communications from the team during the study, and do not receive any
feedback on their energy use. We will use the data on the
control groups’ usage to account for environmental factors
which effect electricity use (cold weather, mass use of TV
to watch landmark events, et c.) and to allow us to take into
account the fact that simply having an ‘electricity monitor’
in the home may have an effect on the energy behaviours of
the household.</p>
      <p>In addition to the questionnaires, we will conduct
approximately 35 face-to-face semi-structured interviews, with a
purposive sample of subjects. Interviews will occur in
respondents’ homes and involve as many adult household
members as feasible, and will include observation and discussion
of home configuration, energy efficiency features, types of
energy consumed and appliances used. A number of
respondents will be interviewed both before and after the
experiments, in order to benchmark conceptions and practices and
to facilitate identification of changes (these respondents will
be excluded from the field trial analysis). A number of
respondents will be re-interviewed at least six months after the
trial to identify any long term changes in overall levels and
underlying practices. Respondents will receive an additional
incentive for their participation in the interviews. In
addition, we plan three professionally moderated focus groups,
to elicit discussion of the trials and normative discourse in
a social context; the focus groups will be reconvened after a
period of six months to explore the longevity of any changes
in practices.</p>
      <p>Technology
Each respondent who volunteers to take part in the study is
supplied with a box containing three components
1. A current-clamp which attaches to the meter tail and which
transmits usage data every two seconds via a 433 MHz
wireless link.
2. A monitor which stores this data and sends the data to our
server via GPRS using a roaming SIM.
3. A power adapter which supplies the monitor with power
for operation.</p>
      <p>
        There is no real-time display visible to the individuals in the
household. It has been shown [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] that real-time displays are
a powerful tool in effecting behavioural change since they
promote experimentation to see what effect individual
appliances have upon power consumption, but have not been
included in this study in order to focus on the effects of
social feedback.
      </p>
      <p>The monitor and current-clamp make use of a
commerciallyavailable off-the-shelf home energy monitor with a real-time
display. We hide the display from view in the box that
contains the GPRS modem and microcontroller. Using a COTS
solution allowed a significant saving in development time
and the time taken to meet regulatory and safety
requirements.</p>
      <p>As a result of field-testing in the pilot studies, the embedded
controller has evolved through several iterations to account
for network outages, automatically reloads new versions of
firmware as we release them, and can be remotely controlled
in situ to trigger recovery from several abnormal conditions.
Usage information is gathered via GPRS upload by the HTTP
‘GET’ mechanism to a web-server where it is logged in a
relational database. The web-server provides an
passwordcontrolled management interface which allows us to track
the performance of each monitoring unit and participant
household, to determine for example when participants in a
household have not viewed their data on the website, and to track
the frequency of data transmission from monitors enabling
the team to track network outages, request user interventions
such as checking the unit is receiving power, ask the
householder to reboot the unit, et c..</p>
      <p>
        Feedback
Information is supplied to the participants in the individual
and social experimental groups in a number of ways. They
can view information about their electricity use on the
website (see below). They receive weekly emails which
encourage them to maintain their participation in the study.
Individuals known to be infrequent visitors to the website may
receive SMS text messages prompting them to participate, a
mechanism which was shown to be an effective way of
encouraging re-engagement in the initial field trial.
As previously stated, households are assigned to one of three
experimental groups which define the type of feedback they
receive. The feedback provided to households in the social
feedback category is illustrated in fig. 1. We hope to
create the conditions where we may most easily see an effect
of social proof in changing behaviour in the following ways.
Firstly, we attempt to increase saliency as recommended in
[
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] and focus on small geographic areas as recommended in
[
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. Secondly, we provide descriptive and injunctive
feedback in the form of emoticons after Schultz [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ] to reduce
the possibility of the ‘boomerang’ effect. Finally, we
provide easy access to energy saving tips which we hope will
provide householders with the means to lower their energy
consumption. The website also provides the user with views
of his electricity consumption in a context suited to his
experimental group for previous time periods; yesterday, last
week, and the whole of the study thus far.
      </p>
      <p>Initial results from the participants in the twenty-strong
second test indicate that the feedback is viewed as both
interesting and useful, and we look forward to reporting the results
of the full trial in the near future. Recruitment for the main
trial started in January, 2011, and we expect to present
results after the trial in the Autumn of that year.</p>
      <p>
        Novelty
The CHARM Energy Study differs from the work reviewed
above in the following ways. There have been studies
involving more people with monthly feedback on paper-based
bills [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], and studies involving small numbers of people with
weekly paper-based feedback [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ]. We believe that ours is
the first study testing the social norm approach with frequent
automated data collection and feedback. Further, ours is the
first such study in the UK where there may be resistance to
the social norm approach [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ].
      </p>
      <p>
        Conclusion
It is planned [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ] that all UK homes will have Smart Meters
installed by 2020, and the EU Smart Meter market has been
predicted [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ] to be worth 25 Billion Dollars US in the ten
years from 2010 to 2020. Although the emerging UK
standard [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ] mandates that UK Smart Meters will provide
bidirectional communications and support in-house displays, we
are unaware that there is yet a standard for the type of
information that will be displayed to the consumer.
      </p>
      <p>If the study shows a real reduction in domestic electricity
use resulting from social feedback methods, we hope that we
may influence the emerging Smart Meter standard to provide
for this means of change.</p>
      <p>Acknowledgements
This work was partly funded by the Engineering and
Physical Sciences Research Council (EPSRC) and is one of a
series of projects operating under the Research Councils UK
(RCUK) ‘Digital Economy’ Programme. Data transmission
costs have been subsidised by the UK M2M provider,
Wyless Plc in partnership with UK mobile telephony provider,
O2.</p>
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