DESIGN AND DEVELOPMENT OF A SMART WINDOW FOR SOLAR CONTROL OF GLAZED FACADES

Controlling solar gains in buildings is one of the most critical means for energy efficiency, because of their high contribution to overall air conditioning demands, moreover for mild climate areas and for buildings with large glazed facades. Basically, in hot seasons they must be minimized and in cold seasons they must be maximized. This paper reports a novel approach for the production of smart windows with changeable solar transmittance, which can be re-actively controlled and optimized in function of outdoor climatic conditions and internal comfort targets. Solar properties of the smart window in both its configurations have been investigated, showing that the low transmittance state dramatically reduces incoming energy fluxes, as compared with its high transmittance configuration. In addition, it is shown that the whole stratification preserve visual transparency in both states, that it switches from one condition to another within few minutes and the process is absolutely reversible. Then, this paper deals with prototypal development of the technology, leading to the production of the first full scale "smart window" prototype. Concluding remarks about future research are discussed as well.