NOVELTY - A cover assembly (1) comprises covers. The cover A comprises upper surface board (2), solar cell module (6) which is installed in surface of upper surface board, backplate (3) which is extended in downward direction from upper end of upper surface board, and side plate (4) which is connected between one side edge parts of backplate and upper surface board. The cover A is inclined by predetermined angle in length direction.    USE - A cover assembly used for covering upper direction of sewer facility.    ADVANTAGE - The cover assembly reduces construction cost, shortens construction schedule, makes scene of sewer facility favorable, and can make deodorizing of sewer facility be performed appropriately.    DETAILED DESCRIPTION - A cover assembly (1) comprises covers. The cover A comprises upper surface board (2), solar cell module (6) which is installed in surface of upper surface board, backplate (3) which is extended in downward direction from upper end of upper surface board, and side plate (4) which is connected between one side edge parts of backplate and upper surface board. The cover A is inclined by predetermined angle in length direction. The cover B comprises upper surface board, solar cell module which is installed in surface of upper surface board, backplate which is extended in downward direction from upper end of upper surface board, and side plate which is connected between one side edge parts of backplate and upper surface board. The cover B is inclined by predetermined angle in length direction. The cover A and cover B are adjoined. The interior space enclosed by upper surface board of cover A, backplate and side plate, and upper surface board of cover B, backplate and side plate is opened in downward direction while upper surface board of cover A and upper surface board of cover B form a plane. An INDEPENDENT CLAIM is included for a usage method of cover assembly of sewer facility.    DESCRIPTION OF DRAWING(S) - The drawing shows a perspective view of cover assembly. (Drawing includes non-English language text).    Cover assembly (1)    Upper surface board (2)    Backplate (3)    Side plate (4)    Solar cell module (6)