To provide a generator in an athletic field that can utilize sunlight to spectators' seats in the athletic field for power generation when it is not in use except for game.

A solar panel unit 1 is formed by housing a solar panel 7 in a transparent housing body 5 provided with a coupling means 3. A number of the solar panel units 1 are coupled with each other in freely separable manner by means of the coupling means, and they are placed on the upper edges 15a of the backs 15 of the spectators' seats 13 installed in the athletic field. The solar panel unit houses a solar panel in a transparent and flexible housing body, and it is placed on the back of each seat for spectators in the athletic field.