Detecting urban-scale dynamics of electricity consumption at Chinese cities using time-series DMSP-OLS (Defense Meteorological Satellite Program-Operational Linescan System) nighttime light imageries

A better understanding of the spatiotemporal pattern of energy consumption at the urban scale is significant in the interactions between economic activities and environment. This study assessed the spatiotemporal dynamics of EC (electricity consumption) in UC (urban cores) and SR (suburban regions) in China from 2000 to 2012 by using remotely sensed NTL (nighttime light) imagery. Firstly, UC and SR were extracted using a threshold technique. Next, provincial level model was calibrated yearly by using Enhanced Vegetation Index and population-adjusted NTL data as independent variables. These models were then applied for pixel-based estimation to obtain time-series EC data sets. Finally, the spatiotemporal pattern of EC in both UC and SR were explored. The results indicated that the proportion of EC in urban areas rose from 50.6% to 71.32%, with a growing trend of spatial autocorrelation. Cities with high urban EC were either located in the coastal region or belonged to provincial capitals. These cities experienced a moderate to a rapid growth of EC in both UC and SR, while a slow growth was detected for the majority of western and northeastern cities. The findings suggested that EC in SR was more crucial for sustainable energy development in China.