A computer simulation study of the performance of occasionally tilt-adjusted, low concentration parabolic trough collectors using evacuated tube absorbers is presented. Using manual adjustment of 20 times per year, 3-4X concentrators appear to be most suitable for moderate temperature applications (100-200°C). Annual output is comparable to that of stationary concentrators in spite of a higher operating temperature, and relative cost-effectiveness is extremely promising compared to stationary designs because of a low absorber tube requirement.
D. R. Mills, D. R. Mills,
"Occasionally Tilted Low Concentration Parabolic Collectors For Industrial Heat", Proc. SPIE 0441, Intl Conf on Nonimaging Concentrators, (5 January 1984); doi: 10.1117/12.937703; https://doi.org/10.1117/12.937703