Monitoring the electric power consumption by lighting from DMSP/OLS nighttime satellite imagery

In this study, we attempted to estimate the electric power consumption using the Defense Meteorological Satellite Program (DMSP)/Operational Linescan System (OLS) stable light imagery after correction for saturation effected. Digital numbers (DNs) of a stable light image are saturated in the center of city areas. Thus, we developed a saturated light correction method for the DMSP/OLS stable light image using the radiance calibration image of DMSP/OLS nighttime imagery. The comparison between the stable light image for 1999 and the radiance calibration image for 1996-1997 in major areas of Japan showed a strong linear correlation (Y_sta = 17X_rad 102) between the DNs of both images. Saturated DNs of the stable light image could therefore be corrected based on the correlation equation between the two images. To estimate the electric power consumption, regression analysis was performed between statistic data of electric power consumption from lighting and cumulative DNs of the stable light image before and after correcting for the saturation effects using the new and the conventional methods of the cubic regression equation (CRE). There is a stronger improvement of the determination coefficient with the new saturated light correction method (R =0.91, P=4.5·10⁶<;0.05) than with the conventional method (R²=0.81, P=2.6-10⁶<;0.05) from the initial correlation with the uncorrected data (R²=0.70, P=1.7-10⁶<;0.05).