A Review of Linear Fresnel Collector Receivers used in Solar Thermal Technology

Linear Fresnel collectors (LFC) have, among the four technologies of concentrating solar power (CSP), the simpler technology. They have a one axis sun tracking, plane mirrors and a fix receiver. All these elements make them the most suitable for small scales CSP plants adapted to rural area of the Sub-Saharan region. The receiver is an important part of the LFC. There is a wide variety of receivers that differ in the shape of the absorber: mono-tube, multi-tube, plane. The shape of the secondary concentrator or its absence allows to categorize the receivers in a butterfly, compound parabolic concentrator, segmented parabolic secondary concentrator or trapezoidal receiver. Vacuum mono-tube receivers have heat losses between 200 W/m and 270 W/m at an absorber temperature of 350°C. A mono tube receiver at partial vacuum losses more than 350 W/m at 350°C. The lowest heat losses of a multi-tube receiver with a trapezoidal secondary concentrator can reach 500 W/m at an absorber temperature of 350°C. This paper discusses a comparative study of existing receiver designs in order to find the most suitable for rural areas in the sub-Saharan region, i.e. easy to design by hand and low cost. Although they do not have the best thermal performance, trapezoidal receivers with a black-painted copper multi-tube absorber and a glass cover seem to be the most suitable.