NOVELTY - The device has photovoltaic cell provided to convert light energy received by photovoltaic cell device into electrical energy. The light reflecting element is adapted to switchably convert electrical energy into light energy and to switchably reflect portion of light energy received by photovoltaic cell device portion. The light reflecting element is active in primary operation mode, and light reflecting element is not active in secondary operation mode while photovoltaic cell is active.    USE - Photovoltaic cell device such as luminescent solar concentrator. Can also be used in solar panel, solar module, and photovoltaic array.    ADVANTAGE - Since the illumination effect can be enhanced by remote phosphor layer, the light energy can be generated in response to illumination by light emitting and reflecting element. Thus, the light from sun can be captured by the photovoltaic cell during daytime the reflector can be made transparent. The reflector can be turned on to reduce light absorption during night time and reflect the light produced by the light sources. Since the control unit switches light emitting and reflecting element and switchable reflector to active state in response to output of the light sensor, the lighting settings can be adapted and ambient intelligent lighting system can be obtained. Since the light generated by light source is coupled into the waveguide in front of solar cell and solar concentrator and coupled out at desired positions, the desired illumination and lighting function can be achieved without reducing efficiency. Hence, the efficiency of photovoltaic cell device can be improved and light absorption photovoltaic cell device can be reduced.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for method of controlling photovoltaic cell device.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic block diagram of the control system for photovoltaic cell device.    Solar panel (25)    Light sources (55)    Switchable reflector (70)    Sensor (85)    Control unit (90)