Quantitative assessment of passive design measures on building energy demand in arid climates. Case study: Solar decathlon middle east houses, Dubai

Abstract

The United Arab Emirates (UAE) and Dubai in specific have set ambitious goals to lower emissions and increasing energy efficiency, with a particular focus on buildings. Efforts toward these goals have led to regulations such as Dubai Building Code (DBC) and Al Sa’fat that define design measures to reduce building energy demand. However, accurately assessing the impact of these design measures remains a challenge, especially for the passive ones. This study aims to quantify how improving further the current passive design requirements affects the building energy demand in Dubai, specifically single-family residential buildings (villas). In 2023 the residential sector accounted for around 30% of the electricity consumption in Dubai and around 90% of the new buildings were villas. We used the Solar Decathlon Middle East (SDME) competition houses as case studies, which allow us to study the energy performance of high performing real building in a controlled environment. The assessment is done through building energy modelling with Ideal Cooling Loads to assess passive design isolated from active design, followed by parametric variations of the passive design measures. As expected, reducing the thermal transmittance of walls, roofs, and glazing, individually or in combination to each other, lowers the Total Energy Intensity, up to 10%. However, reducing floor thermal transmittance has a contrary effect, that goes to -4%, due to lower ground temperatures. Following the findings of this study we derive recommendations for future building regulations and building designers, and for future research.