Reproduced Solar Radiation Derived from Electric Current of Solar Cell for Daytime Meteorological Study

During the daytime, the electric current was generated by the incidental sunlight onto the solar cell. The current variation linearly depended on the variation of the solar radiation each day. The linear relationship between the electric current generated by solar cell, and the incidental solar radiation can successfully be used as an index to convert back the current to the solar radiation in term of the use of the solar radiation for meteorological purpose in the area that had no any solar instrument except the solar cell. In the 6 months experiment period from January 1st to June 30th, 2012, it was demonstrated that the relationship between the variation of the electric current and solar radiation was linearly with mean of R2 = 0.913. The linear relationship index was different on each month based on the monthly solar radiation. The mean overall index was 0.107. By using the index, we were successfully reproduced the solar radiation from the electric current generated by solar cell. The results showed good agreement with R2 =0.95 of the relationship between the reproduce solar radiation and the original one. The case study of June 7th, 2012 showed good results of the use of the reproduced solar radiation in the study of the cloud covering the sky. In the morning from around 7.00 LT to 12.30 LT, the reproduced solar radiation slightly increased with small variation indicating that it was in the normal sunny condition. After 12.30 LT, the reproduced solar radiation dropped down to the low level of solar radiation until the end of the day at around 17.30 LT. It was indicated that this area was covered by cloud from around 13.00 LT to around 17.30 LT. This result agrees quite well with the satellite image illustrating the cloud was covered this area at the same time of the dropdown reproduced solar radiation.