TECHNOLOGY FOCUS - MECHANICAL ENGINEERING - Preferred Device: In the tandem photovoltaic cell device, the lower absorber layer is made of the semiconductor material selected from copper tin sulfide (Cu2SnS3), iron sulfide (FeS2), copper indium gallium selenide (CuInGaSe2), or copper indium selenide (CuInSe2). The lower absorber layer comprises a thickness ranging from about first predetermined amount to a second predetermined amount. The lower electrode layer, the lower transparent conductor layer, the first upper transparent conductor layer, and the second upper transparent conductive oxide layer are respectively first electrode, second electrode, third electrode, and fourth electrode. The bottom cell is configured to absorb electromagnetic radiation in a red wavelength range. The lower glass substrate material is selected from a float glass or a soda lime glass. The lower electrode layer is made of a material selected from aluminum, silver, gold, or molybdenum. The lower window layer is made of material selected from an n-type material. The lower transparent conductive oxide layer is selected from a transparent indium oxide or a zinc oxide. The first upper transparent conductor layer comprises a p+ type transparent conductor layer is selected from a zinc bearing species or zinc oxide (ZnO):aluminum (Al) (AZO). The first upper transparent conductor layer comprises a p+ type transparent conductor layer comprises a zinc telluride (ZnTe) species or AZO. The first upper transparent conductor layer comprises a p+ type transparent conductor layer is doped with at least one or more species selected from copper (Cu), chromium (Cr), magnesium (Mg), oxygen (O), aluminum (Al), or nitrogen (N). The intermediary glass material comprises a low iron glass, where the intermediary glass material comprises the thickness of 1 millimeter and less. The upper p type absorber layer is selected from CuInS2, Cu(In,Al)S2, or Cu(In,Ga)S2. The upper n type window layer is selected from a cadmium sulfide (CdS), a zinc sulfide (ZnS), zinc selenium (ZnSe), zinc oxide (ZnO), or zinc magnesium oxide (ZnMgO). The second upper transparent conductive oxide layer is selected from In2O3:Sn (ITO), ZnO:Al (AZO), ZnO:B, or SnO2:F (TFO). The upper glass material comprises a low iron water white glass having a thickness of 2 millimeters and greater. The first edge sealing material comprises a first edge tape and the second edge sealing material comprises a second edge tape.