Before and After a Home Energy Audit: Changes to Consumption Behaviour

Michelle Grace ScottBehave Energy Conference 2014

Kā Rakahau o Te Ao Tūroa

Centre for SustainabilityAgriculture Food Energy Environment

Our Objectives

Drier homes

Warmer homes

More energy efficient homes

Average Temperatures

Summer Winter

Dunedin 15.3 °C 6.6 °C

Oxford 16.4 °C 3.6 °C

Housing Situation

• New Zealand’s relatively poor housing stock• A lot of Dunedin houses are damp, single

glazed with inadequate insulation• Strategies such as energy feedback may not be

appropriate• Goal is to use energy more efficiently and be

warmer & drier rather than overall consumption reduction

Intervention

• Home Energy Audits–Expert advisor–Personalised tailored

advice–Not common in NZ–Uptake was difficult

Research QuestionsHow the home energy audit affects:

Energy awareness and energy literacy

Behaviour around energy in their homes

Social norms around energy issues

The Energy Cultures Framework

Energy practicesNorms

Material culture

Self-reinforcing

“Material culture”

Material culture

Heating devices Energy sources

Insulation House structure

“Energy practices”

Energy practices

Turning on heater

Putting on jersey

Maintaining heating technologies

Drawing curtains

“Norms and Aspirations”

Norms and aspirations

Social aspirations

Environmental concern

Expected warmth levels

Maintaining traditions

Material culture

Energy practices

Norms and aspirations

Have

The Energy Cultures Framework

Material culture

Energy practices

Norms and aspirations

Have

The Energy Cultures Framework

Do

Material culture

Energy practices

Norms and aspirations

Have

Think Do

The Energy Cultures Framework

MethodPre survey (behaviours, knowledge, social norms, material culture)

Home Energy Audit

Post survey (behaviours, knowledge, social norms, material culture)

< 1 week

4-6 months

Motivations

• “We would like to find out what we can do to keep in heat and run our house energy efficiently”

• “In our house we are either cold in the cool months or we spend a great deal trying to heat the space. We'd like to be warmer with less cost and waste.”

• “I am interested in sustainability and would like to not waste much energy. I like to keep my costs low on long term and do like low tech approaches.”

Demographics

<29,000 30 - 59,000 60 - 89,000 >90,0000

5

10

15

20

25

30

35

40

NEVBlueskin

Rent -

private

owner

Rent -h

ousing N

Z

Own debt fr

ee

Own with

mortg

age

Other0

10

20

30

40

50

60

70

NEVBlueskin

Income Housing

Perc

enta

ge

Perc

enta

ge

Everyone who had audit lived in a separate house, with average of 8 rooms

Pre Audit MeasuresArea N Save Money Save

EnvironmentBlueskin 21 4.52 (.98) 4.19 (1.21)

North East Valley 22 4.55 (.74) 4.64 (.66)

Area N KnowledgeBlueskin 21 6.38 (1.36)

North East Valley 18 6.83 (0.92)

No differences between suburbs on knowledge or reasons to change energy consumption

Pre-Audit Measures

• No significant differences between suburbs on their material culture

Area N MaterialsBlueskin 21 6.38 (1.36)

North East Valley 18 6.83 (0.92)

Energy Use After AuditHow energy use has changed since audit

Percentage

More efficient 38.1%Energy use hasn’t changed 23.8%More frugal 16.7%Make my home more comfortable 16.7%Use as much as I want 2.4%

Energy Literacy

• No significant differences on energy literacy before and after audit

N Mean (maximum 1)Pre-audit 19 0.84 (0.20)Post-audit 19 0.70 (0.24)

Practices

• Dry your laundry outside• Do the laundry on cold wash settings• Pull the curtains at night• Turn appliances off at the wall (not just leave

them on standby)• Reduce heating in unoccupied rooms

Practices

• After the audit, more people reported practicing energy efficient behaviours

(t (19) = -2.69, p = <0.05)

N Mean (max 5)Pre-audit 20 3.79 (0.31)Post-audit 20 4.01 (0.37)

Materials

• How much of your floor is covered with good quality, heavy duty carpet?

• What proportion of your windows have well fitted and heavy curtains/drapes?

• In what proportion of your home do you have energy saving lights?

Material Changes

• After the audit, more people reported having improved their material culture

N Mean (max 5)Pre-audit 20 2.90 (0.64)Post-audit 20 3.54 (0.51)

(t (19) = -4.58, p = <0.01)

Household Changes

• “Installed pelmets and lined the curtains. Installed under floor insulation.”

• “Increased amount of insulation - much more to do. Investigated and still working on ways to harness sun's energy to improve inside temperature.”

• “New thick curtains in bedrooms. New fireplace. Ceiling insulation. Turning more things off at the wall.”

How helpful were these organisations/people?

Information source Mean helpfulness rating (max 5)

Sustainability community groups 4.23Tradespeople 4.00Friends and family 3.91Energy Efficiency and Conservation Authority

3.91

Internet 3.88TV 3.46Colleagues 3.40Power company 2.95Newspapers 2.85

Influencing Others

• “Yes, I have older children in their own homes and I have taught them things that I learnt.”

• “Have passed on some thicker curtains to other residents.”

• “I have shown people my windows and told friends about the positive effect. Some are now interested in doing more research on filling the draft gaps and double glazing.”

Conclusions

• Audits helped to change practices• Audits also led to changes in material culture• Audit encouraged people to discuss energy

changes with others• Can be effective way of encouraging change in

overall energy culture

Thank You

michelle.scott@otago.ac.nzBehave Energy Conference 2014

Kā Rakahau o Te Ao Tūroa

Centre for SustainabilityAgriculture Food Energy Environment