NOVELTY - A tile lath (4) is provided with an elongate electrical conductor (7, 8) which is covered with a resilient insulating layer. A solar cell film (6) is attached to an upper side of a roof tile (5). A conductive piercing device is connected to the roof tile and by which electrical energy generated in the solar cell film is drawn off. The piercing device and the insulating layer are adapted such that the piercing device pierces through the insulating layer for the purpose of making electrical contact between the piercing device and the conductor when the roof tile is placed on the tile lath.    USE - Roof such as indoor.    ADVANTAGE - The alignment between roof tile and tile lath is largely unnecessary because placing is not limited to a discrete position. The assembly of a roof can proceed more quickly. The corrosion can be prevented, when the insulating layer is resilient and adapted to cover the electrical contact between the piercing device and the conductor after placing of the roof tile. The resilience ensures that the space between the piercing device and the resilient layer is limited to a minimum, thus reducing the danger of corrosion. The roof tile can also be placed more easily since lesser requirements are made of the form of the piercing device. An erroneously placed or damaged roof tile can be moved and either set it back or replace it without the possibility of the conductor corroding. A silicone layer is suitable because of its shape-recovering capability so as to provide for a good closure when the piercing device pierces through the layer and to avoid that the conductor becomes exposed after removal of the roof tile. The piercing device comprises a conductive, point-like structure so as to pierce the insulating layer easily. The tile laths are fixed to battens which are in turn mounted on a roof boarding. The battens lie in a direction from the ridge of the roof toward the roof gutter, perpendicularly of the tile laths to be placed later, so as to make a batten suitable as carrier or mounting medium for the conductor. The use of flexible solar cell film makes it possible to follow the contours of a roof tile. The solar cell film has the undulation during placing of a flexible solar cell film over the undulation of a roof tile, results in a more efficient solar energy absorption.    DESCRIPTION OF DRAWING(S) - The drawing shows a perspective view of a portion of the roof.    Tile lath (4)    Roof tile (5)    Solar cell film (6)    Electrical conductors (7, 8)    Support structure (9)