Rebound from a practice perspectiveTowards a better understanding of people’s interactions with heat pumps in Norway

Tanja Winther and Hal Wilhite, SUM, University of OsloCREE Workshop 16-17 September 2013, Oslo

Heat pumps Likely reduction of electricity consumption: 35%(ref. Enova, Norsk Varmepumpeforening)

Presumed chain

Goal:Energy savings

Means:Introduce efficient technology that provides the same service as the one replaced

Result:Energy savings

Rebound in energy acknowledged

• Direct rebound: changes in what people do with energy undermine energy saving potential

• Indirect rebound: saved costs lead to increased consumption in other fields (e.g. travel)

“We find that the electricity savings potential of the increased use of heat pumps in Norwegian homes is completely offset by changes in consumption. Households with heat pumps maintain higher indoor temperatures, consume less alternative fuels and engage less in energy-saving behavior than other households.”

SSB Discussion Papers No. 737, April 2013

Social practice theory

• Attention to the routines of everyday life• Interrelationship between material and socio-cultural factors • People are not interested in energy per se, but the services that

energy provides: light, heat, comfort, convenience, cleanliness

Bourdieu (1977), Giddens (1984), Shatski (1996), Reckwitz (2002), applied to energy consumption Warde (2005), Halkier et al. (2011), Wilhite (2013)

New technology: presume 3 important drivers for change (sources of agency)

• Practical knowledge  embedded in the routines into which the technology is inserted

• Cognitive knowledge conveyed in the know-how transfer related to the new technology

• The “scripts” for use embedded in the new technology (Akrich 1994)

Our study

• Question: What do people do when they rebound?• Aim: Widen the understanding of the rebound effect through a

practice perspective by analysing people’s interactions with heat pumps in Norwegian homes

• 28 in-depth interviews (15 winter /13 summer time)• Recruited through SSB-participants + other means• Oslo, Akershus, Vestfold and Trøndelag• Mostly detached houses, owned by the family• Researchers, assistants, interview guide, interviews recorded +

transcribed

 Time of acquisition of heat pump/ moving into home with heat pump

 Installation phase/just moved1-2 years3-5 years6-15 years

 38

125

 11 %29 %43 %17 %

 Type of heat pump

 Air-to-air Air-to-waterGeo thermal, water-to-water

 2224

 79 %7 %

14 %

 Gender of respondents

 MaleFemaleBoth male and female

 48

16

 14 %29 %57 %

 Age of respondents

 20s and 30s40s and 50s60s and 70s

 6

139

 21.5 %46.5 %32 %

 Small children living at home

 YesNo

 1513

 54 %46 %

Findings

• All the families (one exception) cherish the heat pump for providing increased comfort

• Some – but far from all – think they have saved energy and costs. Only 4 said that economy was their unique reason for investment.Three families reported to have saved 15-30%.

• More a feeling of having saved than a documented effect (few keep track of consumption)

• Nobody knows what saved money is spent on• 18% use the pump for cooling• Reflexivity: Deny rebound, but detailed accounts reveal that

rebound has indeed taken place

The reference: existing heating habits

• Oil burners and non-working stoves

• Extensive use of wood

• Electric heating

A mix of heating sources before and after: complex interplay in terms of costs and also other aspects of the practices

Electricity consumption increases, cost of

fossile fuel avoided

Electricity consumption

increases

Electricity consumption decreases

Various devices together provide comfort• “The heat pump helps distributing the hot air from the stove to

other parts of the building”

• “I keep on the electric heating cables in the entrance at given temperature, and these will turn off automatically when the pump has provided a satisfactory indoor temperature in the whole house.”

And sometimes frustration

• «I can get angry when the pump does not respond when I try to adjust the temperature with the remote control.»

Acknowledging agency of heat pumps

• «My sister calls her heat pump Fredric» (laughs)• «It will idle...» (den vil hvile seg…)• «She will sometimes run wildly» (Hu blir noen ganga

spinnvill)

Appreciating increased comfort

• I remember how awful it was to enter the cold entrance in my parents’ house, I don’t want that

• Waking up in the morning, we had to start the oven before doing anything else and wait for the heat

• Coming home from work, fetching wood, heating the stove and starting to cook dinner while the children wanted attention…

• We like to hear the children at night time, so we keep the doors open

• I enjoy the fragrance coming from the newly washed clothes which I leave to dry in front of the pump

Script for use: distribution of heat

Listening to expert advice

• Central position in the home• «He said that we should not bother to turn it on and

off because it will not make us save energy and it can damage the pump in the long term»

• «Will save energy»

Summary of findings (I)

• 12 of 25 families (48%) purchased a heat pump at the time of a major renovation, some expanding space

• Shift towards heating the whole house and not just parts of it• Indoor temperature reported to be the same, but most families

let the heat pump run constantly day and night and when being away from the house

• Heating season reported to be the same as before (September-June), but exceptions

• Users perceive increased comfort, a sense of reduced costs and being environmentally friendly:

«It’s very special to feel like being environmentally friendly and staying in a house heated to 23 degrees”

Summary, observed chain (2)

Goal:Energy savings

Means:Introduce efficient technology that provides the same service as the one replaced

Result:Energy savings

Goals:ComfortSave moneyAvoid hassle with woodAvoid oil burnerFind suited solution when renovatingCooling

Means:Introduce heat pump to be used in combination with existing heating sources and shape heating practices and other practices which fulfull the varous needs of the family

Results:Increased comfort Convenience/controlImproved air qualitySafetyEnergy savings??

Conceiving comfort rebound, three dimensions• Spatial rebound: expansion of heated space

– Enlarged physical space– Enlarged heated space

Impact of know-how: circulation of air

• Temporal rebound: expansion in heating time– Drive: time management– Impact of know-how, but also mixed advices: uncertainty

• Residual, mixed purposes – In our material: attending to children, better air quality,

drying clothes etc.

Three drivers for change that together shape new practices

PRACTICAL KNOWLEDGE embedded in existing routines

COGNITIVE KNOWLEDGEKnow-how new technology

SCRIPTSEmbedded in new technology

e.g. «I was feezing, we had to do something»

e.g. expert: «Don’t turn it on and off»

e.g. heat pumps designed for circulating air, require open space

Thank you