NOVELTY - The modular cover has modules that consist of pair of covering panels (1,2) forming specific angle with respect to each other. A third group of profile (7) is provided with hinge connection unit between pair of panels. The modules consist of fourth group of profile (21) and fifth group of profile extended between first and third profiles, and includes upper seat to retain insulating panel (8) between fourth and fifth profiles and lower seat to retain photovoltaic panel (9) between fourth and fifth profiles. The fourth and fifth profiles are at distance spaced apart from panel.    USE - Photovoltaic modular cover for building such as industrial buildings.    ADVANTAGE - The upper seat retains an insulating panel between the fourth and fifth profiles, so that the insulating panel can provide improved overall energy efficiency of the building by the thermal insulation and air-sealing properties. The fourth and fifth profiles are at distance spaced apart from the insulating panel, so that the overheating of the photovoltaic panel can be prevented. Thus the energy efficiency can be aided in an efficient manner. The seats in the fourth and fifth profiles allow for the possibility of installing the photovoltaic panel at a later or last stage in the process of laying the cover, while in the meantime the insulating panel provides a watertight and airtight cover for the building. Thus the cost associated with providing the photovoltaic panel can be postponed to a later point in the installation process. Hence high up-front costs can be avoided. Therefore great flexibility and ease of the installation process can be achieved. The complexity, cost, dimensions and weight of the cover can be reduced while maintaining a robust design.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for procedure for laying of modular photovoltaic cover onto covering beams of building.    DESCRIPTION OF DRAWING(S) - The drawing shows a front view of module applied between two covering Y-shaped beams of building.    Covering panels (1,2)    Third group of profiles (7)    Fourth group of profile (21)    Insulating panel (8)    Photovoltaic panel (9)