Overheating is a problem in solar thermal energy systems as elevated temperatures during stagnation result in reduced lifetime of collector materials. It is equally an important issue with regard to highly glazed facades since their high passive gains imply substantial energy needs for air conditioning in summer.
Antonio Paone’s thesis work addressed the problem of high temperatures through the development of “smart” thermochromic coatings for glazed surfaces. These coatings consist of vanadium dioxide, a durable inorganic thermochromic material, which undergoes a reversible crystal structural phase transition accompanied by a strong change in optical properties at 68°C. Through controlled doping the transition temperature has been lowered to around 49.5°C, which makes the material suitable for window and collector coatings.
Antonio Paone’s thesis was supervised by Dr Andreas Schueler, Leader of the Research Group “Nanotechnology for Solar Energy Conversion” and directed by Prof. Jean-Louis Scartezzini, head of the EPFL Solar Energy and Building Physics Laboratory.