Performance of a Multicrystalline Photovoltaic Module in Critical Climatic Conditions of Western Rajasthan, India

Abstract

The energy yield of a Photovoltaic (PV) power plant depends upon the dc power output of the PV module. The irradiance and temperature are the two most important parameters affecting the dc power output. This paper analyses the dc power output of a multicrystalline PV module in the realistic environmental condition with respect to solar irradiance, ambient temperature and cell temperature. The real time data is collected from a 5 MW grid connected solar PV plant located in Jaisalmer, a district in Western Rajasthan. The paper brings forward a crucial and valuable fact that the modules work more efficiently at high temperature and high solar irradiance. For a multicrystalline PV module with maximum dc power output (P max ) at STC condition equal to 118.687KW, analyzed over a period of one year it is found that maximum dc power output (P dc ) at 22 o C ambient temperature and 40 cell temperature is only 72 KW while maximum P dc at cell temperature around 50-55 o C and ambient temperature around 35-38 o C is 90-92KW. Slight negative temperature coefficient for P dc with respect to temperature is observed if ambient temperature and cell temperature is greater than 35 o C and 50 o C respectively. However power output increases in direct proportion to irradiance outweighing the change in temperature. Higher the irradiance, higher is the dc power output, higher is the efficiency and correspondingly higher is the energy yield of the PV module. The multicrystalline PV module works efficiently and gives high yield in the extremely high temperature of Western Rajasthan. Rajasthan which receives world second largest radiation has the capability to meet the energy demands of India and the world as well if solar energy is harnessed in appropriate way.

The Defining Positive Role of High Cell Temperature on the Performance of a Multicrystalline Solar Photovoltaic Module

“…In summers when the temperature is very high V dc is also high and nearly constant for about 8 hours irrespective of irradiance showing that at high cell temperature V dc becomes independent of irradiance, the most significant positive effect of high cell temperature. In the time duration when V dc is constant the P dc curve follows POA curve and correspondingly I dc curve as shown vide figure [16][17][18][19]. The dc current varies in direct proportion to irradiance and is verified by figures 20-23.…”

“…Attari et al showed production in summer was more compared to winters for sites located in north of Morocco [13]. Few researchers showed that irradiance outweighs the negative effect of temperature leading to much higher energy yield in summers as compared to winters [14,15,16,17].…”

Unfolding Extraordinary Positive Effect of High Temperature and High Irradiance on DC Power Output of a Multicrystalline PV Module: A Case Study of Western Rajasthan

“…Vasisht et al [4] have shown that ambient temperature between 20 to 38 o C has positive correlation with the efficiency of a monocrystalline PV system. The results of Garg et al [5] also show that dc voltage decreases with increase in temperature only for ambient temperature greater than 38 o C and cell temperature greater than 50 o C. Garg et al [6] have shown that dc power output varies in direct proportion to irradiance outweighing the change in temperature. Power output at cell temperature 50-55 o C was far greater than power output at 40 o C. Garg and JB [7] have also shown that dc voltage attains a point of saturation maintaining nearly constant value in the range of 80-85% of its rated value for cell temperature greater than 49 o C. Mustapha et al [8] while evaluating the performance of a polycrystalline solar photovoltaic module under Maiduguri-Nigeria weather conditions have shown that current generated is directly proportional to solar irradiance and is almost independent of temperature.…”

Evaluating DC Voltage Temperature Coefficient of a Multicrystalline Module in Actual Environmental Conditions of Western Rajasthan, India

“…This paper illustrates comprehensive study of real field data to analyse the effect of high cell temperature and POA on the dc voltage of a grid connected multicrystalline module and to estimate temperature coefficient for multicrystalline module in real field conditions which is far different from laboratory conditions. The work done is extension of my previous two papers [4,5]. In previous paper [4] dc voltage was analysed with respect to ambient temperature and GHI (Global Horizontal Irradiance) but results show that V dc has better correlation with cell temperature and POA.…”