Abstract: An energy conversion device includes a roofing material having a covered channel through which fluid can flow, the channel configured such that a ratio of the cross sectional area of the channel to the length of a perimeter of the cross section of the channel is less than 8 mm.

Abstract: The present invention relates to an energy conversion device including a roofing material having one or more open channels and one or more photovoltaic modules, characterised in that the one or more photovoltaic modules is bonded directly or indirectly to the roofing material so as to form one or more covered channels through which fluid can flow. In this manner an energy conversion device may be formed in a standard roofing material combining the benefits of Photovoltaic modules to generate electricity and a solar thermal collector to provide heat from the Sun in a single integrated device.