We present a study conducted to obtain optimum tilt angle and orientation of a solar panel for the collection of maximum solar irradiation. The optimum tilt angle and orientation were determined using isotropic and anisotropic diffuse sky radiation models (isotropic and anisotropic models). The four isotropic models giving varying optimum tilt angles in the range of 37 to 44°. On the other hand, results of the four anisotropic models were more consistent, with optimum tilt angles ranging between 46–47°. Both types of models indicated that the collector tilt should be changed four times a year to receive more solar radiation. The results also indicate that the solar panel should be installed with orientation west or east of due south with a flatter tilt angle. A 15° change in orientation west or east of due south results in less than 1% reduction of the total solar radiation received. For a given optimum tilt angle, the effect of photovoltaic/thermal (PV/T) orientation west or east of due south on the outlet temperature was determined using a one-dimensional steady state heat transfer model. It was found that there is less than 1.5% decrease in outlet temperature for a PV/T panel oriented up to 15° east or west of due south from March to December. This result indicates that existing roofs with orientations angles up to 15° east or west of due south can be retrofitted with a PV/T system without changing the roof shape.

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Stationary battery systems are becoming more prevalent around the world, with both the quantity and capacity of installations growing at the same time. Large battery installations and uninterruptible power supply can generate a significant amount of heat during operation; while this is widely understood, current thermal management methods have not kept up with the increase of stationary battery installations. Active cooling has long been the default approach of thermal management for stationary batteries; however, there is no academic research or comparative studies available for this technology. The present work presents assessment of different active cooling methods through an experimentally validated computational fluid dynamics simulation. Following model validation, several cooling system configurations were analyzed, including effects from implementing either a perforated vent plate or vortex generators. The vent plate was observed to greatly increase cooling performance while simultaneously promoting temperature uniformity between batteries. Vortex generators were shown to marginally increase cooling performance, yet, future research is recommended to study the effects and improvement of the design. The average battery temperature for the vented model is reduced by approximately 5.2 °C, while the average temperature differential among the batteries was only 2.7 °C, less than the recommend value (3 °C) by ASHRAE/IEEE Standards.