Horizontal global solar radiation is important information for many industries, such as energy management for power grid and agricultural activity. This paper proposes an estimation method of horizontal global solar radiation using photovoltaic (PV) system for constructing of data base. The proposed method has two steps. Firstly, global solar radiation on tilted surface is estimated using by short-circuit current and open-circuit voltage monitored in PV system. Next, the solar radiation on tilted surface converts to the horizontal global solar radiation based on Erbs model. Accuracy of the proposed method has been verified by comparing the estimated values with measured value obtained by silicon pyranometer. The proposed method has the following advantages: (1) The estimation of the solar radiations that match the characteristics of crystalline silicon PV modules. (2) Increase in the number of the observation points due to the use of the PV system.
