A simplified model based on clearness index for estimating yearly performance of hybrid PV energy systems

Abstract

A simplified model for estimating the energy contribution of PV converter in a hybrid PV-wind system is presented. The simplified model determines the yearly solar fraction, that is the fraction of energy demand provided by PV, and the remaining loss of load (LOL) is assumed to be provided by wind turbines. The novel model is based on simulation results derived from 8 years of measured hour-by-hour solar irradiation data from five different locations in the world. The system performance is simulated by the PV-wind energy simulation program of the Cardiff School of Engineering (ARES). An hourly constant load profile is assumed.The performance of a PV system is primarily dependent on the solar irradiation distribution in a given location for the period of time in question. The new model correlates the location dependence observed in the yearly solar fraction curves of different data sets with one of the most characteristic solar irradiation distribution parameters, the yearly clearness index of the respective solar irradiation data. The new model requires the yearly clearness index value, which is commonly available for most locations throughout the world, as input. As the novel model is validated with solar irradiation data from different locations in the world, it could be used for predicting the solar fraction in a hybrid PV system with a very high level of accuracy, for a wide range of climates.

Modeling and Parameter Extraction of PV Cell Using Single- and Two-Diode Model

“…The specifications of these modules are summarized in Table 1 Table1. (3)(4)(5) shows the I-V curves for modules for different levels of irradiance and temperature. It can be seen that for varying irradiance, despite the modeling curves do not match experimental data in all points, the tow diode model strongly agrees to experimental data than the four-parameter and fiveparameter models for all types of modules, except for the thin-film (ST40) module at low irradiance of about 200W/m² where the five-parameter modeled curve is closer to the experimental data than fourparameter and tow diode models.…”

“…An overestimation up to 40% was reported as compared to the rated power output of PV modules [1,2]. The growing demand of photovoltaic technologies led to research in the various aspects of its components from cell technology to the modeling, size optimization, and system performance [3][4][5].…”

Effect of different load profiles on the loss-of-load probability of stand-alone photovoltaic systems

“…In its most general form, the LLP is given as a function of two variables namely SLR, which is the solar to load ratio, and BLR, which is the battery to load ratio [25][26][27]. These parameters can be expressed as…”

An Improved Mathematical Model for Computing Power Output of Solar Photovoltaic Modules

“…An overestimation up to 40% was reported as compared to the rated power output of PV modules [1,2]. The growing demand of photovoltaics technologies led to research in the various aspects of its components from cell technology to the modeling, size optimization, and system performance [3][4][5]. Modeling of PV modules is one of the major components responsible for proper functioning of PV systems.…”