A probabilistic approach to determine PV array size and battery capacity used in grid-connected PV systems

This paper focuses on optimizing the PV array size and capacity of the battery used in grid-connected photovoltaic systems from the perspective of residential electricity consumers. In our approach, battery capacity and PV array size are obtained with respect to energy dispatch schedule stored in the battery energy storage system. To achieve reliable results, some uncertainties, such as the stochastic output power of the PV system and the electricity load are considered. A Point Estimation Method (PEM) is used to generate samples of the uncertain variables. In order to account for operation of the system after installation and to reduce the computational burden, data clustering techniques are implemented to produce scenarios for net load of the customer. Then, the proposed Mixed Integer Programming (MIP) model of the optimization problem is solved. A Feed-in Tariff and a time-of-use rate structure are selected and the effects of electricity tariff on optimal sizing of the system components are studied. In this work, the effects of PV array size on the optimal battery capacity are investigated. Also, the role of considering real assumptions of the battery life and inverter cost on changing limits to feasibility of these systems are evaluated.