PURPOSE: To collect the radiant heat of the sun at focus for effective utilization all the time by putting on the track a heat collector with a parabolic sectional area by switching a photoelectric switch so as to match the direct ray angle of the sun sight.

CONSTITUTION: By the rotation of the earth, the incident angle to the heat collector 1 is inclined, the incident ray from the slit 13 of the photoelectric switch box is also inclined at the same time, and the solar incident ray is irradiated onto the photoelectric switch 12 made of a semiconductor, fixed in the inside of the photoelectric switch box 2. And, the storage battery 8 charged by solar battery, etc., has a circuit connected to the photoelectric switch 12 and the relay 7, and the photoelectric switch 12 which received the incident ray operates to flow current from the storage battery 8 to operate the relay 7. The relay 7 closes the circuit of the storage battery 8 and the motor 4, the motor 4 is operated to incline the heat collector 1 through the reduction gear 3, and tracking movemenet is continued to the position of the direct ray angle of the solar radiation.