Abstract: The solar concentrator includes a carriage movable along an inclined, ground anchored ramp. A first weight at the end of a pulley carried first cable, biases the carriage upwardly of the ramp slope. A number of mirrors are pivotally carried by the carraige, and reflect sunrays toward a heat sink absorber. A second weight biases the mirrors to pivot in one direction, while a third weight biases the mirrors in an opposite direction. The operator can put into operation the second or third weight as he chooses. Gravity induced up or down carriage displacement allows sun tracking adjustments on an incremental, day to day basis. Gravity induced mirrors pivotal motion allow sun tracking adjustments on a continuous basis during each daylight period. Hence, all year long, solar rays reflected by the mirrors remain convergent toward the absorber.