摘要 |
A cylindrical shaped solar cell having a water vapor transmission rate of 10−4 g/m2·day or less is provided. The cylindrical shaped solar cell unit comprises a substrate that is either (i) tubular shaped or (ii) rigid solid rod shaped, a back-electrode circumferentially disposed on the substrate, a semiconductor junction layer circumferentially disposed on the back-electrode, and a transparent conductive layer circumferentially disposed on the semiconductor junction. A transparent tubular casing is circumferentially disposed onto the cylindrical shaped solar cell. A first sealant cap is hermetically sealed to a first end of the transparent tubular casing. A second sealant cap is hermetically sealed to a second end of the transparent tubular casing. In some instances, the solar cell unit is a monolithically integrated arrangement of solar cells. In some instances, the solar cell unit is a solar cell. |