Urban form, thermal comfort and building CO2 emissions - a numerical analysis in Cairo

This paper describes a modelling analysis of the role different urban forms might play in reducing building CO2 emissions. The study was based on a residential building in a Cairo neighbourhood under summer conditions and developed a base case urban layout covering an area of 1 km2. Three alternative urban strategies were then created around the same residential building. The software package EnviMet was used to assess external microclimate and thermal comfort conditions in each urban layout. Localised weather files were then created as inputs to the dynamic thermal modelling package DesignBuilder, which predicted the CO2 emissions associated with mechanical cooling to achieve comfort in the building. It was possible to observe some differences in CO2 emissions as a result of the different urban forms.

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