Metabolism and Environmental Impacts of Household Consumption: A Review on the Assessment, Methodology, and Drivers
The focus when analyzing the environmental requirements and impacts of the economic system is usually placed on production activities. But all production is associated with final consumption, and recently many studies have also been dedicated to final consumption. This article comprehensively reviews the biophysical assessment of households from the point of view of materials and energy required and emissions and wastes resulting from household consumption patterns. Although the aggregation bias and methodological variability make comparisons difficult, some patterns can be recognized. Results show that for many Organization for Economic Cooperation and Development (OECD) and a few developing countries, household metabolism has been mainly assessed from the energetic perspective, stressing household responsibility for emissions of greenhouse effect gases and climate change. Few studies deal with other emissions and wastes. There is a lack of information about material requirements, too. Environmental input-output (I-O) analysis and life cycle assessment are the methods usually employed, together with the use of economic, environmental, and expenditure information. Information about direct inputs and outputs is complemented with data on the environmental requirements associated with the consumption of goods and services. Multiregional I-O techniques have been used to capture upstream requirements in an attempt to avoid errors owing to truncation and domestic technology assumptions. Housing, food, and mobility are the most important consumption categories, but the shares of these categories in the requirements are different according to environmental, socioeconomic, and demographic factors. Finally, challenges for further research are discussed based on the need for new methodological developments, as well as the potential of the metabolic narrative to elaborate information relevant to sustainable consumption policies.