Life Cycle Assessment performance comparison of small solar thermal cooling systems with conventional plants assisted with photovoltaics

Abstract

Life Cycle Assessment (LCA) allows for the consideration of energy consumption and environmental impacts associated with all the stages of a product's life, from the cradle to the grave. Starting from the results obtained in the IEA SHC Task 38 framework for the LCA of small solar assisted heat driven chillers, the application of such methodology has been extended to systems with a conventional compression chiller assisted by a photovoltaic plant. This study aims to provide a more comprehensive investigation through a comparison of these two families of solar assisted cooling systems (with solar thermal or PV), which is an important topic for studies concerning the research of effective and environmentally friendly systems that exploit solar radiation for cooling and heating purposes. In hot climates, the systems with the PV grid connected plant performed best. Anyway, a comparison of this system with the other systems is not meaningful because the strength of the solar thermal H/C system is the ability to reduce the dependence from the electric grid and to avoid peaks, overloads and power quality variations. Thus, two more configurations were investigated to further define the PV assisted systems, which minimise their interaction with the grid through the use of electricity storages. These systems performed worse than the PV grid connected systems and the solar thermal assisted systems in nearly all the analysed cases.