Nearly zero energy building design and optimization: A residential building transformation in Türkiye

In this study, the energy performance analysis of a representative residential building located in Izmir, Turkey, was carried out, utilizing the DesignBuilder energy simulation program. Heating, ventilation, and air conditioning systems are modeled as detailed in Design Builder in order to consider parameters such as thermal properties of materials, duct layout and airflow dynamics of the system in detail in the analysis. The technical and economic analysis of transforming the building into a nearly zero energy building (NZEB) was performed for eight different retrofit scenarios, including passive and active energy efficiency measures. The most effective scenario, Scenario 8 (S8), reduced the building's annual net primary energy consumption by 96.08% to 7.45 kWh/m²/year. S8's annual CO2 emissions decreased by 100.07% compared with the reference scenario, resulting in −0.042 kg CO2/m²/year. The overall energy performance class of the building was determined using Turkey's national calculation program for the preparation of the energy identity certificate. The energy performance class of the reference building was determined as D, and the class of the building designed according to S8 as A. Investment evaluations were carried out for the retrofit scenarios, revealing that the investment cost for S8, having the lowest net primary energy consumption, amounted to USD 17,565.87. This finding establishes S8 as a more financially viable option in the short term. This study demonstrates the potential of NZEBs in reducing greenhouse gas emissions and achieving sustainable development goals.