Systematic Rotation and Receiver Location Error Effects on Parabolic Trough Annual Performance

Abstract

This report deals with the effects of certain systematic errors on performance and, therefore, their influence on the design of troughs. Systematic rotation error is the angle between the reflector vertex-focus axis and the vertex-sun axis; systematic receiver location error is the vectorial deviation of a receiver from focus. The existence of systematic rotation errors and systematic receiver location errors can have a significant effect on the annual performance of parabolic trough collectors. These systematic errors can exist in addition to errors which are random in nature and which, therefore, can be treated statistically. Systematic rotation errors of 16 milliradians result in annual performance degradation of greater than 30 percent. Systematic receiver location errors can have a similar effect depending upon magnitude. The technique for calculating the influence of systematic errors on performance is outlined and methods of identifying and minimizing these errors are suggested.