Design of a multi-surface solar concentrator

A multi-surface solar concentrator is proposed in this study. The concentrator is designed by improving the light receiving rate of a parabola when the incident angle changes within 0°~20° by adding involute, shifting the involute up, and changing the shape of the parabolic top. The results show that adding involute can effectively avoid light escaping from the bottom, which improves the light receiving rate under large incident angle. The light receiving rate is improved by increasing the height of involute at incident angle of about 5°~15°. Changing the shape of the top of parabola apparently improves the light receiving rate under high incident angle. Finally, the concentrator was tested experimentally. The experimental efficiency of the concentrator at different incident angles was 0.426. The average light receiving rate of 0.868 was achieved through the optical simulation where different losses include the optical loss, such as the absorption and reflection of the glass cover, the absorption of reflectors, the heat loss, etc. Thus, the concentrator provides a stable and efficient energy source.