TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Method: Step (c) is carried out by physical cleaning of physically removing the encapsulant layer and/or chemical cleaning of chemically removing the encapsulant layer. Step (b1) comprises separating a rear face protecting sheet (6) from the photovoltaic module. EXAMPLE - Straight chain low density polyethylene (100 parts by weight), vinyltrimethoxysilane (2 parts by weight) and tert-butyl-peroxy isobutyrate (0.1 part by weight) were mixed and graft-polymerized at a melt stirring temperature of 200 degrees C to cause silane modification resulting in silane-modified straight chain low density polyethylene. Hindered amine-based photo-stabilizer (3.75 parts by weight), benzotriazole based ultraviolet absorber (3.75 parts by weight) and phosphorus- based thermal-stabilizer (0.5 parts by weight) were mixed based on the straight chain low density polyethylene (100 parts by weight) and melt-processed to obtain a master batch. Silane-modified straight chain low density polyethylene (20 parts by weight) with a silane modification ratio of 0.3%, straight chain low density polyethylene (80 parts by weight) and master batch (5 parts by weight) were added and mixed in a film molding machine to obtain a film having a thickness of 400 mu m at a resin temperature of 230 degrees C and a casting speed of 4 m/minute. The polymerized silicon amount of the resulting film (i.e. encapsulant layer) was 60 ppm. The encapsulant layer having a thickness of 400 mu m, laminating a glass plate (transparent front face substrate) having a thickness of 3 mm, a photovoltaic cell formed of polycrystalline silicon, encapsulant layer and laminated sheet composed of a polyvinyl fluoride based resin sheet having a thickness of 38 mu m, aluminum foil having a thickness of 30 mu m and a polyvinyl fluoride based resin sheet (rear face protecting sheet) having a thickness of 38 mu m and adhering under press at 150 degrees C for 15 minutes in a vacuum laminator for production of a photovoltaic module, with the surface of the photovoltaic cell facing up. The encapsulant layer was cut out from the resulting photovoltaic module and its gel fraction was measured to be 0% to obtain the photovoltaic cell.