ABSTRACT
In this paper we propose a comprehensive model for environmentally significant consumption like energy consumption. The immediate purpose is to improve our ability to understand such consumption. The underlying purpose is to improve our ability to predict consumption and to improve our policy recommendations, in particular with respect to designing effective policy instruments. A comprehensive model for environmentally significant consumption is from our point of view one that includes the influence of both internal and external factors of consumption. In other words a model that draws on insights from both internalist and externalist approaches to understanding consumption. The internalist approach sees behaviour ‘mainly as a function of processes and characteristics which are conceived as being internal to the individual: attitudes, values, habits and personal norms.’ The externalist approach sees behaviour ‘as a function of processes and characteristics external to the individual: fiscal and regulatory incentives, institutional constraints and social practices’ (Jackson 2005: 19). Including both internalist and externalist approaches makes it fruitful to focus especially on two disciplines; economics and social psychology, and synthesizing theories relevant for environmentally significant consumption within these disciplines. Social psychology mainly focuses on the influence of internal factors, and is well suited to explaining motivation. Economics, on the other hand, focuses primarily on external factors to explain consumption. Preferences or the motivational factor is considered in most analyses a ‘black box’. Stern (2000) argues that in order to understand environmentally significant behaviours better, we need ‘synthetic theories or models that incorporate variables from more than one of the [classes of models], postulate relationships among them, and use them to explain one or more types of environmentally significant behavior.’ While single-variable studies can demonstrate the explanatory power of particular variables, they do not necessarily give us the ‘comprehensive understanding of particular environmentally significant behaviors that is needed to change them’ (Stern 2000: 418).3 In the following, we will first review the contributions from economics (Section II) and social psychology (Section III). In Section IV we will review
previous proposals for synthesis theories, before developing our own model. Section VI concludes with a discussion of policy implications and the need for further research.
