Consumers’ willingness towards Net Zero Energy Settlements and influence of occupant behaviour on building energy efficiency and indoor comfort in a real case study in Italy

This thesis focus on research activities within the context of the development of a Near Zero Energy (NZE) settlement in a real case study in Italy. This study is part of a wider research project called ZERO-PLUS (acronym of “Achieving near Zero and Positive Energy Settlements in Europe using Advanced Energy Technology”), which is in the International Horizon 2020 programme. The project involves the construction of four real-life case study NZE settlements in Europe, i.e. in Italy, France, Cyprus, and UK. In particular, the Italian settlement is composed of advanced solutions for the building envelope, innovative energy production systems, and integrated resources energy management at the settlement level. However, the objective of obtaining high performance energy buildings can be reached only if considering the contemporaneous influence of technical characteristics and occupancy. Recent studies report that as buildings become more energy efficient, the behavior of occupants plays an increasing role in energy consumption. Therefore, a construction designed to be a Net Zero Energy Building (NZEB) might consume higher than expected if the occupant behavior assumptions made in the simulation process are not respected during the real use. On the other hand, the effective performance of innovative and high efficiency technologies must be checked against predicted performance. In this view, one of the goals of this study is to highlight the critical points that may affect the energy performance, real and expected, of new buildings aimed at meeting the net zero energy standard. The analysis has, therefore, been performed through calibrated dynamic simulation of a continuously monitored building. In detail, indoor comfort settings by the occupants and their interaction with the envelope and the systems directly affect the operation of buildings and related energy uses. Simulation tools (EnergyPlus and DesignBuilder) were employed to demonstrate the potential impact of occupant behavior lifestyles and different household compositions on energy use and thermal comfort conditions. The results clearly reveal their impact. The savings in terms of annual energy consumption can reach up to 60% in the transition from wrong to "green" behaviour. Indeed, this study aims at focusing the attention on the urgent need of reference models related to human behaviors that influence the energy use in buildings, especially in NZEBs. Finally, the importance of psychological factors is also increasingly being recognized in driving the NZEB movement. This study develops an extended Technology Acceptance Model (TAM) to explain consumers' intention to adopt NZEBs in NZE settlement framework and examines it through an extensive survey conducted via social media channels. The results show that subjective knowledge, perceived usefulness, perceived climate change, attitude towards NZEBs in NZE settlement framework and general environmental concern measured by the New Ecological Paradigm (NEP) scale, are the significant psychological determinants of intention to adopt NZEBs in NZE settlement framework. It is also found that lacking subjective knowledge related to NZEBs, and in particular NZE settlements, could be a potential psychological barriers among the surveyed consumers. The identified psychological factors provide references for policymakers to effectively develop consumers' behavioral intervention strategies and allocate resources in NZE settlements promoting schemes.