The paper presents the study of a Hybrid Photovoltaic/Thermal solar water system installed on the roof of buildings. The conducted analysis focuses on a detailed experimental investigation of both the electrical and thermal behavior, and in addition on the holistic environmental analysis during the complete life cycle of the system. The photovoltaic module, used for electricity production, is connected with a heat recovery unit with circulating fluid flow for cooling, while the extracted heat can be used for domestic hot water provision. The aim of this study is to analyze the energy and environmental performance of arrangements based on natural and forced circulation, and to draw general conclusions for the viability of such systems. The environmental performance of the studied devices was evaluated through a detailed Life Cycle Assessment. The energy analysis proves that hybrid systems are more efficient compared to conventional solar thermal and photovoltaic appliances, while they are less environmentally friendly mainly during their production and installation phases. (C) 2018 Published by Elsevier Ltd.