PURPOSE: To reduce costs by providing a heat insulating layer and a photovoltaic plate between at least two translucent plates and two plates, and adding a low-E covering to a surface opposite to the heat insulating layer.

CONSTITUTION: Two transparent plates 10, 12 are spaced apart and interconnected by a spacer 14. A photovoltaic plate 18 is provided on the inner surface of the transparent plate 10 and a transparent plate 10a is placed on the photovoltaic plate 18. Further, a low-E covering 16 is placed on the transparent plate 10a opposite to the transparent glass plate 12. Next, a heat insulating layer 20 filled with an inert gas or a heat insulating material is formed between the transparent plates 10, 12. Therefore, solar energy can be either utilized effectively or shut off.