Predictive Causality of Granger Test for Long Run Equilibrium to Photovoltaic System

The high irradiance in tropical area is certainly favorable to photovoltaic (PV) power output, since the efficiency depends on the solar radiation intensity. However the increase of cells temperature causes conversely a fall of the yield of the modules. This decrease in the performance of PV modules due to temperature effect also causes proportional voltage decrease. This drop in performance is at the expense of destabilisation of the electrical network and if the electrical power output of modules is planned for a total grid injection. A time series may be useful in forecasting another time series and this statistical hypothesis test is called the Granger causality test. In this paper, we show that the Granger causality can be applied to PV parameters time series and an error correction model is used to determine a long term relationship of power output for PV systems.