Urban Geometry Optimization to Mitigate Climate Change: Towards Energy-Efficient Buildings

Abstract

The density of building blocks and insufficient greenery in cities tend to contribute dramatically not only to increased heat stress in the built environment but also to higher energy demand for cooling. Urban planners should, therefore, be conscious of their responsibility to reduce energy usage of buildings along with improving outdoor thermal efficiency. This study examines the impact of numerous proposed urban geometry cases on the thermal efficiency of outer spaces as well as the energy consumption of adjacent buildings under various climate change scenarios as representative concentration pathways (RCP) 4.5 and 8.5 climate projections for New Aswan city in 2035. The investigation was performed at one of the most underutilized outdoor spaces on the new campus of Aswan University in New Aswan city. The potential reduction of heat stress was investigated so as to improve the thermal comfort of the investigated outdoor spaces, as well as energy savings based on the proposed strategies. Accordingly, the most appropriate scenario to be adopted to cope with the inevitable climate change was identified. The proposed scenarios were divided into four categories of parameters. In the first category, shelters partially (25–50% and 75%) covering the streets were used. The second category proposed dividing the space parallel or perpendicular to the existing buildings. The third category was a hybrid scenario of the first and second categories. In the fourth category, a green cover of grass was added. A coupling evaluation was applied utilizing ENVI-met v4.2 and Design-Builder v4.5 to measure and improve the thermal efficiency of the outdoor space and reduce the cooling energy. The results demonstrated that it is better to cover outdoor spaces with 50% of the overall area than transform outdoor spaces into canyons.

The Influence of Buildings Proportions and Orientations on Energy Demand for Cooling in Hot Arid Climate

“…The aforementioned factors that influence building energy performance are more in line with the vision of the American Society of Heating, Refrigeration, and Air Conditioning Engineers (ASHRAE), which highlighted six issues related to building energy use [18]. Such points are the building characteristic, building configurations, outdoor design conditions [19][20][21], indoor design conditions, date and time, and operating schedules. Furthermore, solar energy has a considerable impact on the built indoor environment and energy consumption [22,23].…”

Energy Efficiency Coupled with Lightweight Bricks: Towards Sustainable Building: A review

“…An important aspect of a passively designed building envelope is the reduced energy needed to maintain a comfortable inside temperature [6,16,21]. This method takes into account the heat gain from the outside, which is affected by the building's walls, fenestration, roof [38], foundation, thermal insulation [26,27], thermal mass [39], and external shading systems [40][41][42], into consideration [16,43]. Regardless of the ever-changing weather outside, this crucial aspect is what ultimately decides the quality of the structure and what governs the internal conditions [16,21,43,44].…”

A Study of Strategic Plans of Sustainable Urban Development for Alexandria, Egypt to Mitigate the Climate Change Phenomena

“…In recent times, decision-makers in Egypt are of the opinion that a national strategy should be put in place to ensure the adoption of the most relevant approaches to mitigating climate change in the country, i.e., effort should be directed to the promotion of zero and lowcarbon energy systems to substantially minimize energy consumption, coupled with detailed strategies for adaptation and mitigation (Mahdy et al, 2013). Although the climate has a major impact on outdoor and indoor thermal performance, most Egyptian research studies on climate change are still limited to agriculture, biodiversity, and conservation strategies for historical buildings and heritage sites, particularly in coastal cities such as Alexandria (Mahmoud et al, 2021).…”