To provide a solar cell panel which is installed in a construction such as greenhouse and has a new and simple structure enabling easy operation control.

A light receiving sensor, detecting a direction that receives the maximum light energy in a construction from the intercomparison result of output values of directional light receiving elements provided so as to face in multiple directions, is adopted, and the direction of a solar cell panel 42 in the construction is controlled to face in the direction enabling the maximum light energy reception based on the detection result of the light receiving sensor.