The dual lead worm and wheel have high accuracy and the backlash can be closed to zero, which make dual lead worm and wheel heliostat to accurately reflect the sunlight to the specific position of the solar receiver.
While wearing down or heat-expansion and cold-contraction, the backlash of dual lead worm and wheel heliostat is adjustable to recover the accuracy by adjusting the axial position of the worm. It is not necessary to replace the worms and wheels for maintenance.
Dual lead worm and wheel heliostat is suitable for small mirrors ( 15~25 square meter). When the shadows cover the sun, the other small mirrors can be adjusted by control system to compensate for sunlight to solar receiver. The small mirrors are more flexible than big mirrors.