iSUSTCON

Attempts to encourage sustainable consumption through conventional information campaigns are likely to meet at best with limited success. Little is known about the actual effect of eco-labels, and interest has recently turned to the potential use of “nudges”. Consequently, policy-makers have a range of options available to regulate “green” consumer behaviour (e.g., eco-labels, carbon footprint information, descriptive and injunctive norms, fiscal systems, laws, or some combination of these) but little guidance in how to choose between these options. We aim to provide a common behavioural framework for understanding the separate and combined effects of these regulatory systems, and to evaluate their relative effectiveness in a realistic online grocery consumption setting. An additional aim is to learn about choice architectures for online interfaces that are likely to facilitate sustainable consumption. To do this, we draw on three major findings from our precedent project (INCRESP, funded by the ANR between 2010 and 2015). The first major finding showed that descriptive norms (about what other people do) presented during shopping using a realistic incentivized online shopping platform (Greenshop) results in a small but reliable increase in the number of sustainable items purchased (Demarque, Charalambides, Hilton & Waroquier, 2015). The second major finding, using survey methodology in the transport domain, was that some fiscal measures may influence purchase intentions through both prices and injunctive social norms, and that these effects are independent and additive. However, an overly high financial incentive may have paradoxical effects (Hilton, Charalambides, Demarque, Waroquier & Raux, 2014; Raux, Chevalier, Bougna & Hilton, 2015). The third major finding revealed that while presenting numerical carbon footprint on its own had no effect on consumer behaviour, visualization of an ideal sustainable level for a shopping basket (in the form of a carbon footprint “thermometer”) combined with feedback about the consumer’s personal carbon footprint led to average reductions of 10-15% in the carbon imprint of a consumer basket (Corrégé & Inaudi, 2014). In iSUSTCON we go further by proposing an integrative psychological framework for evaluating the likely information-processing costs (high or low) or motivational effects (positive or negative) of various policy interventions (eco-labels, numerical carbon labels, social and injunctive norms, bonus-malus fiscal systems) which in turn are likely to affect the success of these policy interventions. Unlike INCRESP, we focus extensively on eco-labels and make a hitherto unmade distinction between intra-categorical eco-labels and numerical carbon labels that are liable to facilitate inter-categorical processing. This distinction is important, as inter-categorical processing should a priori lead to product substitutions (e.g., meat and dairy by fruit and vegetable) which lead to greater carbon footprint reductions than most intra-categorical substitutions (e.g. standard jam and pasta by “bio” products). We propose a programme of empirical research which will test predictions about the effectiveness of these policy measures in different conditions (Work packages 2-4), using student samples in Aix-Marseille and Toulouse. On the basis of these findings, we will then compare the effectiveness of selected policy measures in a representative sample of the French population using the same controlled setting, namely the Greenshop shopping platform? These data will then be subjected to econometric modelling in order to draw policy implications (Work package 5, Toulouse and Lyon). This analysis will help identify general principles that can be transposed to guide policy makers in other domains of consumption (e.g., domestic energy use, manufactured goods, transport).