Parabolic trough collector (PTC) is one of the most widespread solar concentration technologies and represents the biggest share of the CSP market; it is currently used in various applications, such as electricity generation, heat production for industrial processes, water desalination in arid regions and industrial cooling. The current paper provides a synopsis of the commonly used sun trackers and investigates the impact of various sun tracking modes on thermal performance of a parabolic trough collector. Two sun-tracking configurations, full automatic and semi-automatic, and a stationary one have numerically been investigated. The simulation results have shown that, under the system conditions (design, operating and weather), the PTC's performance depends strongly on the kind of sun tracking technique and on how this technique is exploited. Furthermore, the current study has proven that there are some optimal semi-automatic configurations that are more efficient than one-axis sun tracking systems. The comparison of the mathematical model used in this paper with the thermal profile of some experimental data available in the literature has shown a good agreement with a remarkably low relative error (2.93%).
