Improving interventions for the long-run : a systematic literature analysis of interventions for residential energy consumption reduction using a theory of motivation

Sammanfattning: To address climate change, global greenhouse gas (GHG) emissions in the residential building sector, accounting for 39% in Sweden, need to reduce. While technological improvements and behavioural change are two commonly used strategies, the former is limited by rebound effects that range from 15-20% in Sweden. Focussing on individual behaviour is imperative. While Psychology (behavioural-based) and Sociology (practice-based) offer distinct understandings on unsustainable energy consumption and design of interventions, one, called feedback has been identified to be effective, albeit limited by lack of motivation and (in)ability to produce long-term reductions. To overcome these, use of additional motivational strategies have been recommended. As no specific theory of motivation has been used to investigate interventions, this thesis used the Theory of Self-determination (SDT) to investigate how interventions from both behavioural-based and practice-based approaches motivate resident individuals to reduce energy consumption for long-term reductions, and reductions in rebound effects. Specifically, it asked what co-occurrences exist between the fulfilment of three psychological needs (autonomy, competence and relatedness) and long-term reductions. It used a systematic literature review to analyse 40 studies including peer-reviewed studies (past 10 years) and grey literature that evaluated changes in energy consumption using an intervention involving feedback in the residential context. Ten interventions were classified into four different levels of extrinsic motivations. No studies using interventions from practice-based approach or aiming at reducing rebound effects were found. Most studies used behavioural-based approach but some gave considerations to practice-based elements. Long-term reductions were found to co-occur with the fulfilment of psychological needs (autonomy, competence and relatedness) although only six studies reported long-term reductions. Conversely, a lack of fulfilment of psychological needs was found to co-occur with fall-back to higher consumption in the long-term. Based on the data, how the fulfilment of needs should be done is stressed. Autonomy should be taken into account as interventions themselves either support or thwart autonomy, specifically rewards that were found to reduce autonomy and co-occurred with fall-back on high consumption in the long-term. Competence support can be enhanced through improving feedback that meets the informational and motivational needs of individuals. Further, group-based interventions can play a greater role as they provide more opportunities to support relatedness and motivation. Lastly, taking a practice-based approach can improve the design of interventions, especially with respect to rebound effects as practice-based approaches take a richer account of different factors (material, embodied skills and meanings) that are suggested to better support need fulfilment.