Abstract: In a preferred embodiment of the invention, a flat-plate solar cell type unit includes a plurality of individual cells in parallel flow arrangement and relationship with one-another, as well as physically being substantially parallel to one-another extending along longitudianl elongated axis thereof, each cell being adjustably intermittently rotatable in a direction around its longitudinal axis, such that the angle of incidence of the sun-light rays is adjustable for each individual cell type unit by rotation around its respective longitudinal axis, the plurality being simultaneously adjustable by an interconnecting lever mechanism.