This was designed and made about 28 years ago. It might be practical and especially where high temperatures are needed. Sections of this could be molded and bolted together. The axle aligns with the axis of the earth and thus a turning system (made later and not shown) simply rotated this unit the same speed the earth rotates, yet in the opposite direction, and thus the collector stayed focused on the sun. All the suns rays would reflect to hit the central pipe. The central pipe was made to extend over the ends of the trough to capture the rays reflecting on an angle when the sun was high as in June, and in Dec when the sun was low. In March and Sept the sun struck the collector squarely.
I was young around 20 when building it, my mother soon passed away, and I got interested and involved with other things. It was a lot of work and was made out of metal, plywood and acrylic mirror. The collector measured 10 x 20 ft. and was set on a pivot line largely aligned with the North Star, and adjusted slightly as the North Star is not exactly aligned with the axis of the earth.