NOVELTY - The bifacial thin film solar cell useful as vertical glass walls around a building, comprises a first (100) and a second transparent substrate (120), a first solar cell module arranged on the first transparent substrate, an insulating layer (108) arranged on a metal layer (106) of the first solar cell module, a second solar cell module arranged between the insulating layer and the second transparent substrate, and a layer for gluing a third transparent conductive layer and the second transparent substrate. The first solar cell module comprises a first transparent conductive layer.    USE - The bifacial thin film solar cell is useful as vertical glass walls around a building, and for reducing carbon dioxide production by installing it on rooftops of building structures.    ADVANTAGE - The bifacial thin film solar cell has better conversion efficiency for converting the light energy into the electrical energy at low light intensity, and increased electric power generating capacity.    DETAILED DESCRIPTION - The bifacial thin film solar cell useful as vertical glass walls around a building, comprises a first (100) and a second transparent substrate (120), a first solar cell module arranged on the first transparent substrate, an insulating layer (108) arranged on a metal layer (106) of the first solar cell module, a second solar cell module arranged between the insulating layer and the second transparent substrate, and a layer for gluing a third transparent conductive layer and the second transparent substrate. The first solar cell module comprises a first transparent conductive layer patterned to form electrodes, first solar cell units disposed to correspond with the respective electrodes, and first metal layer serving as one of electrodes of the first solar cell module as well as a reflective layer. The first metal layer is patterned to form electrodes that correspond with the respective first solar cell units. The first transparent substrate is a transparent plastic substrate or a glass substrate. The second transparent substrate is a transparent glass substrate. The second solar cell module comprises second transparent conductive layer patterned to form electrodes on the insulating layer, second solar cell units formed on the second transparent conductive layer and disposed to correspond with the respective electrodes of the second transparent conductive layer, third transparent conductive layer patterned to form electrodes on the second solar cell units and disposed to correspond with the respective second solar cell units, and second metal layer patterned to form electrodes on the insulating layer. Each first solar cell unit is formed using amorphous silicon, or is a tandem structure formed using amorphous silicon and micro silicon.    DESCRIPTION OF DRAWING(S) - The diagram shows an application of the bifacial thin film solar cell.    First transparent substrate (100)    Conductive layers (102, 110)    Metal layer (106)    Insulating layer (108)    Second transparent substrate. (120)