Assessing the impact of energy efficiency measures on building performance and resident behaviour : a case study of social & private housing in Malta

Abstract

Energy efficiency behaviour is a complex matter which is related to the interaction between human behaviour and energy consumption. Understanding residents' behaviour could help to mitigate emissions from Malta's building sector, which has witnessed a rise in greenhouse gas (GHG) emissions over the past two decades. The aim of this dissertation is to analyse the energy building performance as well as the behaviour of residents within Malta’s first energy efficient social housing project, the Tal-Ftieh complex. Additionally, a sample of beneficiaries from the Irrinova Darek and Regulator for Energy and Water Services (REWS) Roof thermal insulation and double-glazing financial support initiatives were also included in the study. This research involved a mixed-method approach, which included interviews, temperature and humidity monitoring within the dwellings using data loggers, collection of data from energy bills, and energy performance calculation utilising Design Builder software specifically for the Tal-Ftieh housing project. The results from the DesignBuilder software indicate that the Tal-Ftieh housing apartments are energy efficient as their energy performance is lower than the national average. However, the data collected from the latest available energy bills shows relatively higher energy consumption and also notable variation amongst the participants. Moreover, their daily per capita energy consumption also tends to exceed that of participants from both the REWS and Irrinova Darek schemes. This highlights the important role of residents’ energy behaviour. As regards thermal comfort, the measured indoor temperature of the Tal-Ftieh participants exceeded the international guidelines on several occasions. Furthermore, the measured indoor humidity levels were also high for all participants most of the time, especially for the participants from the REWS scheme, who reside in terraced houses. Meanwhile, the results from the interviews showed that the tal-Ftieh participants had poor knowledge regarding the energy efficient measures installed in the building and this affected their energy behaviour. This scenario contrasts with the REWS and Irrinova Darek beneficiaries for whom the energy efficiency measures constituted an investment risk. Another important finding from the research was that the primary motivator for investing in energy efficient measures is cost savings. Based on these findings, the dissertation presents a number of policy recommendations to enhance energy efficiency behaviour in Malta and make progress towards reducing emissions from the residential building sector.