A hybrid roof covering element, which suitable for simultaneously heating a medium and generating electricity, and which comprises a single or multiple transparent layer, a flexible thin film solar cell sheet with a heat capacity of less than 3.5 kJ/m.sup.2 K and a thermally insulating material, and a medium to be heated. The flexible thin film solar cell sheet comprises a carrier, a back electrode, a photovoltaic layer, and a transparent conductive front electrode and has a heat capacity of less than 3.5 kJ/m.sup.2 K. This hybrid roof covering element has a response speed of more than 5.7.multidot.10.sup.-4 K/J if the medium to be heated is air and a response speed of more than 1.multidot.10.sup.-4 K/J if the medium to be heated is water.