Declining household greenhouse gas footprints in Germany: Decomposing the contributions of working time, consumption, mobility, energy efficiency and decarbonization between 2000 - 2019

Abstract Understanding the drivers of household greenhouse gas (GHG) footprints is crucial for designing measures accelerating emission reductions. Well-documented drivers are demand, energy efficiency and decarbonization of energy supply, while mobility and esp. working time have received less attention. Herein, the drivers of German household energy and GHG emissions footprints from 2000–2019 are decomposed using extended Kaya Decompositions. Footprints are declining at -1%/year, due to improving energy efficiency and decarbonization overcompensating the growth of per-capita and per-hour incomes. Private mobility footprints decline by -1.4%/year, driven up by growing distances, car-dominated modal splits and growing air travel, compensated by improving energy efficiency and decarbonization, slightly decreasing numbers of trips and stable expenditure on mobility. Aggregate working time is growing, which drives up footprints, while increasing part-time employment resultin small reductions of average per-capita working time. Part-time work is one form of working time reduction for which assumptions of the Kaya Decomposition are fairly realistic. However macro-economic feedbacks and potentially negative social side-effects of part-time work need to be addressed to design equitable policy measures. Remaining research issues are the roles of work-related trips and mobility on company expenses, delivery services and transport of goods, and targeted analyses for socio-economic groups.