Investigative Review of Design Techniques of Parabolic Trough Solar Collectors

Parabolic trough solar collectors (PTCs) are among the most cost-efficient solar thermal technologies. They have several applications, such as feed heaters, boilers, steam generators, and electricity generators. A PTC is a concentrated solar power system that uses parabolic reflectors to focus sunlight onto a tube filled with heat-transfer fluid. PTCs performance can be investigated using optical and thermal mathematical models. These models calculate the amount of energy entering the receiver, the amount of usable collected energy, and the amount of heat loss due to convection and radiation. There are several methods and configurations that have been developed so far; however, it is usually difficult for a designer to choose the appropriate method or configuration for his application. The present work investigates different PTC configurations and methods of solution, compares their efficiency and accuracy, summarizes their key behaviors and trends, and improves the available methods by maximizing the positives and minimizing the negatives among them. We investigated three methods and seven configurations. The findings suggest that optimizing the collector structure, tracking system, and reflector can lead to high PTC performance and reduced capital costs. After investigating and comparing the recent mathematical models, the study identified a clear deficiency in estimating the output temperature. Three PTC's solution methods are investigated, and a novel method is developed to give more accurate estimations of the output temperature.