A Framework for Designing Energy Efficient Dwellings Satisfying Socio-cultural Needs in Hot Climates
Buildings are responsible for the largest share of energy consumption in the world. The effects of buildings on environment and people have generated interest especially in the developed world on how to reduce the significant energy consumption by the building subsector. Moreover, it shows the significance of the building sector in global efforts to reduce the effect of climate change and global energy consumption. The major challenge with buildings in countries in hot climates for example Libya is thermal discomfort especially in residential dwellings causing overdependence on mechanical cooling systems. Thermal discomfort and high-energy consumption in buildings are connected to socio-cultural factors and the approach to the design of residential buildings. Benghazi city, which is the second city and the capital of the eastern region of Libya has witnessed significant growth in population due to its economic prosperity and job opportunity. This has significantly increased the rate of construction of new dwellings and challenges with housing development. This research aims to produce a framework for designing energy efficient dwellings satisfying socio-cultural needs in a hot climate. The research adopted a mixed method approach to generate data that would guide the development of the proposed framework. Measurements and observation survey of 72 existing villas were conducted to determine climatic elements in and around buildings and to gather robust data on building elements. A questionnaire survey of 72 householders was conducted to generate data on the design of houses, open spaces, the perception of comfort and energy consumption in buildings. Moreover, 12 design professionals were interviewed to seek their opinions on the design of houses in terms of the social aspect and climate of Benghazi, the study context. Furthermore, a simulation study of a typical contemporary residential villa was conducted for a detailed investigation of the level of thermal comfort and energy consumption in existing buildings. All the data collected were analyzed using an appropriate method of analysis, which include Excel, content analysis and energy assessment tool, DesignBuilder. The findings showed that 51% of all the householders’ surveyed were not satisfied at all with the level of privacy in their outdoor open spaces. In addition, design professionals’ in the study area supported the need for a future sustainable housing development that placed emphasis on socio-cultural factors and the local climate. Further findings revealed that although the level of clothing for women was higher than men, women were comfortable at a higher temperature than men. Other findings showed that there are thermal discomfort and high-energy consumption in buildings due to the contemporary approach to the design of buildings that have little consideration for socio-cultural factors. Householders and design professionals agreed that energy efficiency could be achieved in buildings in the study context through the adoption of social and climatic design principles. The improvement measures conducted in the case study building showed 84% savings in terms of energy demand. The proposed courtyard design using the proposed framework led to a savings of 65% in terms of energy demand. Despite the high savings recorded and achieving the thermal comfort for the improved case study, it did not meet the privacy and other socio-cultural requirements for the study context. The prototype courtyard design did not satisfy comfort requirements using natural ventilation but met privacy demand by building occupants and can improve family cohesion among other benefits. Socio-cultural dimension is an important principle in sustainable buildings concept. Hence, it might be difficult for building users to be satisfied with a building that achieved energy target but failed to satisfy the occupant’s requirements. Therefore, the prototype courtyard design was preferred for the study context despite its lower energy saving capacity. The prototype courtyard house confirmed the relevance and applicability of the proposed framework for promoting energy efficiency in buildings in hot climates, particularly in Benghazi. Moreover, important recommendations were made regarding selected areas for further research towards advancing this study.
- PhD