One or more embodiments of the present invention are directed to a photovoltaic system. The system comprises photovoltaic cells, arranged side-by-side to form an array of photovoltaic cells. It further involves a cooling device, which comprises one or more layers, wherein the layers extend opposite to the array of photovoltaic cells and in thermal communication therewith, for cooling the cells, in operation. The one or more layers are structured such that a thermal resistance of the photovoltaic system varies across the array of photovoltaic cells, so as to remove heat from photovoltaic cells of the array with different heat removal rates, in operation. One or more embodiments of the present invention are further directed to related systems and methods for cooling such photovoltaic systems.