How does population declining and aging affect residential energy demand in Japanese cities?

After having reached its peak in 2010, Japanese population is gradually declining and aging. Population declining and aging is what Japan has never experienced before. While its impacts on economy and society attract public... [ view full abstract ]

After having reached its peak in 2010, Japanese population is gradually declining and aging. Population declining and aging is what Japan has never experienced before. While its impacts on economy and society attract public attentions, its impacts on the environment do not. Since many Japanese cities are active to achieve their ambitious targets in CO2 emissions reduction, it is worth to explore the implications of population declining and aging for their energy consumption and CO2 emissions. This study aims to investigate the impacts of population declining and aging on urban residential energy demand in particular, which is closely linked to urban CO2 emissions, using the data of Japanese cities. Since urban residential energy demand is determined by the energy demand per household and the number of urban households, the study first investigates the impacts of population declining and aging on the number of urban households. The data shows that the number of urban households is increasing under population declining and aging. This happens because of an increasing number of elderly-single and elderly-couple households. An increasing number of urban households implicates a decrease in an average number of urban household members under population declining (since ‘urban household members’ = ‘urban population’ ÷ ‘the number of urban households’), which is likely to result in an inefficient energy use in households. Then, the study conducts a multiple regression analysis to investigate whether there is a significant impact of population aging on energy consumption per household. Its results show that the impact is positively significant. (264 words)