Comparison of Solar Tracking and Fixed-Tilt Photovoltaic Modules in Lodz

The world energy consumption has exhibited high growth over the last several decades. Alternative energy sources like photovoltaic (PV) systems generate electricity, reduce pollution air, and have little environmental impact. The commonly used fixed-tilt solar panels, however, have low efficiency and high production cost. Thus, it takes a long time to obtain a return on the investment. Solar trackers increase the efficiency of PV systems and are therefore more attractive from a financial point of view. In order to design tracking systems that will be efficient, it is necessary to analyze the results during various periods during the year and over their lifespan. Thus, we performed a comparative study between fixed-tilt panels and the tracking system installed in Lodz, Poland. Fixed-tilt panels are at normal to the Earth's surface (90 deg from horizontal plane) and are attached to a building façade, azimuth 180 deg (S direction) with 15 cm ventilation gap so slight efficiency drop may be presumed. We performed short- and long-term analyses of the solar tracking and fixed-tilt systems, which allowed us to conclude that the panels tracking the sun had an additional gain of energy during the year as compared to the fixed-tilt panels. During some months, however, the solar tracking system did not produce as much energy as the fixed-tilt, vertically positioned panels. These results might be useful in designing and constructing solar tracking PV systems.