Experimental Investigation of a Line Focus Solar Collector Using Flat and Parabolic Reflector

In solar thermal technology, line focus is one of the major categories of solar collectors. They are used to produce either steam or process heat in many applications. In the technology of line focus, sun radiation is directed into the receiver to establish and sustain a line focus. The principal contributors to this technology are parabolic troughs and linear Fresnel collectors. In this paper, an idea of a combination of parabolic and flat reflectors is hypothesized for minimizing the current problems of existing line focus solar collectors. The stationary receiver is mounted in the focal line of parabolic trough. Tracking is only provided to flat reflectors that reduce the tracking cost. A prototype with aforementioned modification is developed and tested for experimental investigation. The thermal performance of the prototype for different operating conditions has been evaluated. Maximum thermal efficiency is reached around 55% that competes with the performance of parabolic trough collector. The average temperature difference of 6.85 °C is noticed, which is 1.14 °C higher than the tested parabolic trough collector.