Disclosed herein is an illumination unit and the method of operation thereof, characterized in that it comprises: a photovoltaic module (A), a ceiling light fixture (B), a supporting structure (A1), a shaped line (B1), two side wings (B2), a certain number of spaces (C), optical elements/means (C1), a control unit (D), an electric storage unit (E), a separate printed circuit (F), a string (F1), a cooling fan (G).