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To improve solar energy gain by the photovoltaic (PV) modules, a novel double-axis solar tracker was developed in the present study. The proposed system worked based on both active and passive methods of sun tracking using electromotor and gas actuator, respectively. The electromotor oriented the module in the east-west direction based on the principle of the chronology of the sun, and in the north-south direction, the change in the gas pressure, due to the temperature change, activated a pneumatic cylinder to rotate the module. The evaluation tests were carried out at the different modes of tracking (including east-west, north-south and double axis). The results showed that the available solar energy on the PV module increased by 5.03%, 33.75% and 38.78% using the tracker at the north-south, east-west and double axis modes, respectively. This, finally, improved electricity generation of the PV module by 4.82%, 31.43% and 36.25%, respectively. Moreover, employing the tracker system led to an increase in operating temperature of the PV module. Based on the operating temperature of the module with the tracking system, it was proposed for using in the photovoltaic-thermal collectors. The designed system could track the sun trajectory with the accuracies of 0.6% and 8% in the east-west and south-north directions, respectively.

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These days, societies' need for energy increased due to the expansion of societies, industries, and technology. The production of electricity from renewable energy sources such as solar energy, which does not harm the environment and has little pollution, has attracted the attention of many researchers and engineers. This article will present a new plan for the dual polar axis solar tracker, its design and construction in laboratory dimensions, and the experimental evaluation of its performance using the open-loop control method. For this purpose, after examining the advantages and disadvantages of the previous designs, a new and different conceptual design for the tracker is proposed. Among the features of the proposed tracker, we can point out the ability to combine, install and operate quickly and easily, the self-locking feature, and the ability to rotate 360 ​​degrees around both axes. This tracker has no restrictions for use in different geographical areas, including areas near the North or South Pole and in the early and late hours of the day when the direction of the sun's radiation is strongly inclined. In the following, the detailed design of the proposed detector and the presentation of the open-loop control method will be discussed. Finally, by conducting experimental tests, the production power of the proposed detector is evaluated in comparison with a fixed solar panel. Based on the results, the electricity energy produced from the proposed solar tracker is 49% more than the fixed solar panel.