Measuring energy sufficiency: A state of being neither in energy poverty nor energy extravagance

There is growing interest in energy sufficiency (ES); however, it remains conceptually debated and contested. This study presents a novel approach to measuring ES using unique microdata on the energy consumption of Japanese households. This approach determines lower and upper thresholds regarding domestic energy consumption for each household type and then identifies whether people really meet an adequate level of domestic energy services, with their diverse energy needs considered. The result illustrates that most people in Japan live in ES, despite about one-tenth being in energy poverty (EP) and one-twentieth in energy extravagance (EE). In addition, this study empirically clarifies the characteristics of people in ES, as well as those in EP and EE. People in ES and EE generally belong to higher income groups, live in larger houses, and are less committed to energy-saving behaviours; the opposite applies to people in EP. As a policy implication, this study suggests more progressive energy tariffs and carbon pricing, as well as improvement in access to renewable energy for the EP population, to engender an inclusive low-carbon energy transition and allow everyone to achieve ES.