Reprint of: To each their own? The greenhouse gas impacts of intra-household sharing in different urban zones

Decreasing household size is a global trend, driven by urbanization and multiple other socioeconomic trends. Going solo poses a great environmental challenge, as the possibility to benefit from scale economies in consumption and its greenhouse gas impacts is not taken advantage of. In other words, understanding of intra-household sharing patterns of different consumption categories is increasingly important in climate change mitigation. This paper explores the relationship between household sizes, urban structures, and greenhouse gas impacts of lifestyles. When urban areas grow outwards, the household sizes also grow. As a result of this, the increase in intra-household sharing seems to alleviate the negative GHG implications of urban sprawl, which is highly logical but yet not comprehended. Thus, the rise of collaborative consumption offers potential to reduce the greenhouse gas emissions of solo dwellers, and compensate for the lower intra-household sharing with inter-household sharing.