A method of operating a hybrid power and heat generating device, which device comprises: - a photovoltaic solar power collector configured to collect solar power from solar radiation received on an active side of the photovoltaic solar power collector; and - a heat exchanging unit configured to cool the photovoltaic solar power collector, which heat exchanging unit includes a cooling plate (106;404;504;704) arranged to transfer heat from the photovoltaic solar power collector to a cooling medium, wherein the heat exchanging unit is adapted to transport the cooling medium away from the cooling plate (106;404;504;704) for heat extraction from the cooling medium, wherein the cooling plate (106;404;504;704) is arranged with a gap from a rear side of the photovoltaic solar power collector, characterized in that the cooling medium is arranged to cool the cooling plate (106;404;504;704) to a temperature which allows water vapor of the ambient air in the gap to condensate into water on the cooling plate (106;404;504;704) in the gap, which method comprises - operating the hybrid power and heat generating device in a normal operation mode in which the gap is at least partly filled with condensed water, which condensed water transfers heat from the photovoltaic solar power collector to the cooling plate (106;404;504;704); and - operating the hybrid power and heat generating device in a security operation mode in which the gap is filled with air to thereby reduce the heat transfer from the photovoltaic solar collector to the cooling plate (106;404;504;704). - a photovoltaic solar power collector configured to collect solar power from solar radiation received on an active side of the photovoltaic solar power collector; and - a heat exchanging unit configured to cool the photovoltaic solar power collector, which heat exchanging unit includes a cooling plate (106;404;504;704) arranged to transfer heat from the photovoltaic solar power collector to a cooling medium, wherein the heat exchanging unit is adapted to transport the cooling medium away from the cooling plate (106;404;504;704) for heat extraction from the cooling medium, wherein the cooling plate (106;404;504;704) is arranged with a gap from a rear side of the photovoltaic solar power collector, characterized in that the cooling medium is arranged to cool the cooling plate (106;404;504;704) to a temperature which allows water vapor of the ambient air in the gap to condensate into water on the cooling plate (106;404;504;704) in the gap, which method comprises wherein the heat exchanging unit is adapted to transport the cooling medium away from the cooling plate (106;404;504;704) for heat extraction from the cooling medium, wherein the cooling plate (106;404;504;704) is arranged with a gap from a rear side of the photovoltaic solar power collector, characterized in that the cooling medium is arranged to cool the cooling plate (106;404;504;704) to a temperature which allows water vapor of the ambient air in the gap to condensate into water on the cooling plate (106;404;504;704) in the gap, which method comprises - operating the hybrid power and heat generating device in a normal operation mode in which the gap is at least partly filled with condensed water, which condensed water transfers heat from the photovoltaic solar power collector to the cooling plate (106;404;504;704); and - operating the hybrid power and heat generating device in a security operation mode in which the gap is filled with air to thereby reduce the heat transfer from the photovoltaic solar collector to the cooling plate (106;404;504;704).