This guide provides information to assist in sizing the array and battery of a stand-alone photovoltaic system. Systems considered in this guide consist of PV as the only power source and a battery for energy storage. These systems also commonly employ controls to protect the battery from being over- or undercharged, and may employ a power conversion subsystem (inverter or converter).This guide is applicable to all stand-alone PV systems where PV is the only charging source. This guide does not include PV hybrid systems nor grid-connected systems. This guide covers lead-acid batteries only; nickel-cadmium and other battery types are not included. This guide does not include the sizing of the system controller, inverter, wiring, or other system components.
Purpose
The purpose of this guide is to provide procedures to size the PV array and battery according to accepted methods, to improve the performance, cost-effectiveness, and lifetimes of stand-alone PV systems. The issues of array utilization, battery-charge efficiency, and system losses are also considered in terms of their effect on system sizing. These procedures are intended to assist designers, manufacturers, system integrators, users, and laboratories with information necessary for sizing, modeling, and evaluating the performance of stand-alone PV systems.
Abstract
New IEEE Standard - Active.A method for properly sizing the PV array and battery for stand-alone PV systems where PV is the only charging source is recommended (in conjunction with IEEE Std 1013(TM)). Load calculations and determination of solar radiation in the sizing of the system need special attention. Additionally, the critical nature of the load in deciding an acceptable annual availability needs to be considered.
