Evaluation and effect of solar irradiance and incident angle on power generation efficiency by using PV modules installed at tilt angle of 90 degree and azimuth angle of east and west

摘要

The authors are studying the diagnostic method of a PV system. In order to diagnose a PV system in detail, it is necessary to separate the loss factors affecting power generation efficiency. h this paper, we are investigating the influence of the solar irradiance aid the incident angle on power generation efficiency of the PV modules installed at tilt angle of 90 degree and azimuth angle of east and west. Especially, the influence of the incident angle on the solar irradiance is estimated in detail by separating into two components such as direct and diffuse solar irradiance. The change of power generation efficiency with time in a fine day is compared with the calculation results by the simulation. As a result, it became clear that power generation efficiency of PV module calculated to take into consideration of the solar irradiance and incident angle of direct and diffuse solar irradiance almost corresponded to measurement one.