There are several possible solutions for placing photo-voltaic solar cells (PV) on a roof. Most solutions include standard individual solar panels being “retro-fitted” onto the roof. Oftentimes, these solutions do not add to the aesthetics of the building – on the contrary! Vitral has a “building integrated” PV solution, where the solar cells are built into the insulting glass unit. In that way, it is possible, in an aesthetically responsible way, to place PV cells onto the roof. As solar cells are mostly placed on the south-most facing side of a roof light, the PV cells in the glass also serve the purpose of reducing solar glare into the building. PV cells can also be used in opening panels.