Phase change materials in a hybrid solar thermal/photovoltaic energy storage system for a residential house

Abstract

Hot water supply has proved to be a subject of great relevance to counter climate change. The integration of solar collectors in residential hot water systems has already been extensively explored, presenting, however, an inconvenient mismatch between energy supply and its consumption. The integration of an energy storage system can counter this obstacle. In this field, phase change materials play an important role, being able to store latent heat. In this thesis, the incorporation of a storage system with phase change materials in a domestic water heating system was investigated. The system proposed in this work consists of a hybrid photovoltaic/thermal solar panel, a water storage tank and a plate heat exchanger with phase change materials. Several configurations were tested and three different phase change materials were studied, with a melting point of around 60 degrees. Simulations were carried out under different climatic conditions, for three different locations: Lisboa, Castelo Branco and Montalegre. The results show that the integration of such a system can lead to a reduction in energy consumption for heating domestic water of around 23% during the summer, and 14% during the winter.