Energy Retrofitting Technologies of Buildings: A Review-Based Assessment

Demand for energy and resources is increasing day by day. The construction industry plays a major role in the consumption of energy and resources. Buildings that were built before energy-efficient sustainable practices became popular consume a larger portion of energy as compared to the new buildings. As a result, enhancing energy performance through retrofitting of those old buildings is a major concern in the construction industry. In the modern built environment, there are many technologies available in the market to enhance the energy performance of such buildings. However, the body of knowledge regarding energy retrofitting technologies is still scattered. Therefore, in this study, a review-based assessment was undertaken to identify energy retrofitting technologies that could enhance energy performance in existing buildings. The Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol was followed during the article screening and selection for this study. Following a systematic filtering process, a total of 149 out of 643 research contributions have been considered for in-depth analysis of energy retrofitting classification and respective energy retrofitting technologies. According to the review, energy retrofitting technologies are categorized into three main aspects; building envelope retrofitting, building system retrofitting, and renewable energy. The study found thirty-seven (37) energy-related retrofitting technologies in the current context. Further, 25 possible energy retrofitting technologies were identified under the six main subcategories, including façade, roof floor, window, door, and orientation. In terms of building system retrofitting, 10 possible energy retrofitting technologies were identified under the HVAC system and lighting system. The remaining two technologies identified under the renewable energy category were solar and wind technology. The review further confirms that the application of energy-related retrofitting technologies has the highest contribution in terms of energy and cost saving of existing buildings. It is expected that this outcome would better guide stakeholders in decision-making with regard to the selection of energy retrofitting technologies in a given context.