THE SIZING OF STAND ALONE PV-SYSTEMS - A REVIEW AND A PROPOSED NEW METHOD

The reliability of stand alone photovoltaic systems is analyzed in terms of the loss of load probability, LLP. A variety of numerical and analytic models for calculating the LLP are described and evaluated using data for three Spanish locations: Madrid, Murcia and Santander, selected because they represent different climatic conditions. It is concluded that numerical models are accurate but complex to use, while analytic models exhibit significant lack of accuracy. A new analytic model, as accurate as the numerical models and as simple as analytic models, is proposed. For each location, the model requires as input 4 different coefficients.