۱- Introduction

۲- Sufficiency – an emerging concept

۳- Understanding consumer behaviour

۴- Towards an integrated description: the Prism of Sustainable Consumption

۵- The affordability approach to describing drivers and determinants

۶- Discussion and conclusions

References

Abstract

It is increasingly obvious that for safeguarding environmental sustainability, eco-efficiency measures will need to be complemented by sufficiency, in particular by strong sustainable consumption. The Theory of Planned Behaviour TPB and Social Practice Theory SPT offer different views on consumer behaviour, and on ways to change it. This paper briefly describes the challenges, discusses the applicability of both theories and their meaningfulness for policy recommendations. We suggest an approach combining results of both bodies of theory, complemented by ideas from political economy, to substantiate the Prism of Sustainable Consumption we introduce as a heuristic sufficiency policy tool. It is useful to identify affordability criteria for change in each dimension, as the basis for deriving suggestions for effective policy interventions. We conclude that (i) effective interventions are possible, (ii) they have to address several dimensions of affordability simultaneously, and (iii) the sufficiency policy space prism can be a useful tool in structuring planned interventions.

Introduction

The Paris Accord requires an almost carbon-free economic system by 2050 (80–۹۵% less carbon emissions) in the affluent countries, and a complete global phase out of fossil fuel use by the end of the century. As the target is a complete, not a partial phase out, efficiency gains can obviously not deliver the required reductions (Alfredsson et al., 2018; for the pitfalls of efficiency see Princen, 2005) and the hopes that substitutes like solar energy or biofuels could be developed to levels replacing the current final energy use while offering a comparable volume of use options are futile (Giampietro and Ulgiati, 2005). Substitute energy sources have a much lower energy density and they require material, land, etc. for their production (Schmidt-Bleek, 2008). Biomass cannot be scaled up from currently 14% of global energy supply to anywhere near 100% (Spangenberg and Settele, 2009), and converting even more fertile land to non-agricultural use is not sustainable in intensively used landscapes such as those throughout the EU. Last but not least for material flows, reduction targets of 80–۹۰% have longs been established as a necessity, for reasons of both environmental protection and global justice (Schmidt-Bleek, 2008; Spangenberg et al., 1999). So while efficiency and substitution, the two prominent market effects, are indispensable, they are not enough. Nonetheless efficiency is the dominating approach in energy policy discussions so far, with concerns about rebound effects coming to the forefront in the last couple of years (IGRC, 2013; Hediger et al., 2018). To avoid these, it is necessary to eliminate the potentially consumption stimulating effects of monetary gains, and that is where sufficiency comes in, addressing consumption levels instead of consumption patterns: it takes sufficiency to make efficiency effective. That consumption has to change is no new insight, however, but an old and inconvenient one (Spangenberg and Lorek, 2002). Making consumption sustainable is already an explicit demand in Agenda 21 (United Nations, 1993). 18 years later, in the run-up for the UNCSD Rio +20 Summit, the United Nations came to similar conclusions. Taking a closer look at technology potentials including renewable energies and organic agriculture the UN concluded that technology is not enough and must be accompanied by behavioural and consumption change (United Nations, 2011). Thus essentially it is long known that sustainable consumption must accompany production efficiency if sustainable development goals are to be met (United Nations General Assembly, 2015). More recently the normative concept of sufficiency, also referred to as enoughness or strong sustainable consumption, has become centre stage, as it has been recognised that the levels rather than the patterns of consumption are decisive for environmental degradation (Mihić and Čulina, 2006; Lorek, 2010; Lorek and Spangenberg, 2014).