It is difficult to determine the input parameters values for equivalent circuit models of photovoltaic modules through analytical methods. Thus, the previous researchers preferred to use numerical methods. Since, the numerical methods are time consuming and need long term time series data which is not available in most developing countries, an improved mathematical model was formulated by combination of analytical and numerical methods to overcome the limitations of existing methods. The values of required model input parameters were computed analytically. The expression for output current of photovoltaic module was determined explicitly by Lambert W function and voltage was determined numerically by Newton-Raphson method. Moreover, the algebraic equations were derived for the shape factor which involves the ideality factor and the series resistance of a single diode photovoltaic module power output model. The formulated model results were validated with rated power output of a photovoltaic module provided by manufacturers using local meteorological data, which gave ±2% error. It was found that the proposed model is more practical in terms of precise estimations of photovoltaic module power output for any required location and number of variables used.

The purpose of this study is to fabricate and analyze an active cooling system for reducing photovoltaic (PV) module temperature and increasing its efficiency. An active cooling system was devised to cool the PV module. Two modules of same specifications were used for this study. One module was cooled, and other was left un-cooled for performance comparison. Solar radiations, wind speed, ambient temperature and temperatures at different points of the fabricated system were measured. The modules were mounted on a frame facing true south at the inclination of the latitude of the location. The measurements were taken during daytime with one hour intervals for two weeks. The temperatures at various points on cooled and un-cooled photovoltaic modules were noted using two different flow rates with 1 lit/min and 2 lit/min. It was discovered that the efficiency of PV module was enhanced from 6% to 7% during study period. The flow rate of 1lit/min was found more feasible for heat extraction as compared to the flow rate of 2lit/min. The wind speed was found to be more helpful for heat extraction from the modules as compared to other climatic parameters.

It is prerequisite to predict the behaviour of photovoltaic (PV) modules in a particular geographical area where the system is to be installed for their better performance and increasing lifetime. For that, models are the easiest and acceptable tools to characterise the behaviour of PV modules in any location. The purpose of this study was to develop an empirical model to predict the influence of temperature on the performance of four different PV module technologies, namely, polycrystalline, monocrystalline, amorphous, and thin film in an outdoor environment. The model has been developed by fitting of one year experimental data using the least squares method. The estimated results of the developed model were validated with real-time data (winter and summer season) and a comparison of other existing model estimates using error analysis with 95% confidence interval. The proposed model estimations confirm that the monocrystalline module performs better in winter and polycrystalline in summer as compared to amorphous and thin film in the study area. During analysis, it is revealed that developed model results are more precise and appropriate among other existing model estimations. It is concluded that the proposed model estimations could be used for the prediction of PV module temperature in similar environmental conditions as that of the study area with more accuracy and confidence. It ultimately helps to develop cost-effective and efficient PV systems.

This study was conducted to appraise climatic conditions for potential applications of solar energy units in Nawabshah and Quetta cities. For that, twenty two annual monthly average data of insolation on horizontal surface, at various slopes on titled surface, air temperature, earth skin temperature was acquired and evaluated through the Statistical Package for the Social Sciences software. It is discovered from the study that Quetta is a more promising place for installation of solar energy applications as compared to Nawabshah as it receives more solar radiations and less air temperature.

A line focusing concentrated solar distillation unit was developed and its techno-economic analysis was carried out using batch flow, continuous flow without and with tracking mechanisms. Physical quality parameters of feed and distilled water samples, water temperature at different points, performance analysis and estimated production of developed unit were examined. The examined quality parameters of distilled water were well below permissible limits. The water temperature inside the concentrated tube was in the range of 107.0˚C to 109.0˚C. The quantity of distilled water was observed to be inversely proportional to the amount of total dissolved solids in the water samples. The measured average daily and estimated lifetime yield from the developed unit during batch flow was 4.0 and 13,621.0 liters, for continuous flow without tracking 5.1 and 19,689.0 liters, and with tracking mechanism 5.7 and 21,758.0 liters, respectively. The continuous flow with tracking mechanism was found as best method for the production of distilled water. The total life cycle cost of the project was estimated to be PKR 62,144.00. The estimated unit cost of the distilled water per liter would be PKR 6.06 for continuous flow with tracking and PKR 9.69 for batch flow technique. ©2019. CBIORE-IJRED. All rights reserved