LAUSR

The high cost of air conditioning during the summer makes it crucial to develop strategies to reduce energy use in buildings, especially in hot arid climates. Nanomaterial-based external window insulation is considered an effective method for achieving this goal. This research examines the effectiveness of using aerogel-based glazing systems combined with passive design techniques to improve energy efficiency in buildings in hot arid regions. This study presents various scenarios, including building orientation and aspect ratio, utilizing field measurements and energy simulations with aerogel-filled windows. This study is two-phased. The first phase compares two rooms with aerogel and conventional glazing in Aswan. The new glazing system made the room 0.3–1.9 °C cooler. The second phase simulated the Egyptian Japanese School in Aswan to assess the effects of aerogel glazing systems and altering the enclosed semi-open courtyard’s building orientation and aspect ratio. Results show that using aerogel glazing systems and altering the building orientation and aspect ratio can significantly reduce energy consumption and improve indoor thermal comfort. The results reveal that Scenario 1, which represents using aerogel glazing in the northern façade, could reduce the average air temperature between 0.30 and 1.49 °C below the base case (BC). Scenario 3, which used aerogel glazing on the southern facade, reduced annual energy consumption by 26.3% compared to the BC. Meanwhile, Scenario 5, a semi-open courtyard with an aerogel glazing system and an aspect ratio of 2.40, could save 25.7% more energy than Scenario 1. The economic viability of the scenarios was also analyzed using a simple payback period analysis, with Scenario 3 having the second-shortest payback period of 4.13 years. By insulating the exterior panes of windows, this study proposes that adopting aerogel glazing systems can make windows more cost-effective and ecologically sustainable.