4. Comparison between old and new NEDO Solar Radiation Database(2)

Abstract

MONSOLA-20 which recorded the monthly mean of solar radiation and METPV-20 which recorded the hourly meteorological data were released by NEDO in 2021. In this study, we compared these data with MONSOLA-11 and METPV-11. Overall, there was a slight trend toward an increase in solar radiation due to the update of the statistical period and improved solar radiation estimation model. We found that slope solar radiation was changed in conjunction with horizontal solar radiation, and that there is a seasonal variation between horizontal solar radiation and slope solar radiation.