抄録
We propose a simple guidepost for the installation of photovoltaic systems using the field test data in Miyazaki，Japan. Concentrator photovoltaic (CPV) system generates electricity only from direct solar irradiance. Therefore，the output of CPV system is drastically influenced by scattering ratio due to humidity，aerosols，and yellow sand，The scattering ratio varies with the seasons. We proposed an insta11ation guidepost of CPV systems using the scattering ratio and gradient global irradiance. We measured the output of CPV and flat-p1ate multi-crystalline Si PV systems. We have measurement systems for direct and global solar irradiance. Therefor，we can obtain the scattering ratio. Gradient global irradiance was also measured. These field test results were analyzed and a guidepost was derived. Based on the guidepost，we can decide which systems of CPV or Si PV systems is suitable at a candidate site for system installation
