Exploring the potential of nearly zero energy retrofitting for generic office buildings in Cairo, Egypt

Energy consumption of the buildings sector has increased dramatically over the past decade. In Egypt, existing buildings consume 60% of electrical energy. Improving existing buildings through energy retrofitting and using different techniques of integrated PV may serve as a step towards improving the energy performance in buildings in Egypt and achieving nZEB levels. This research aims to explore the potential of achieving nZEB levels through retrofitting office buildings’ typical prototypes in Cairo, Egypt, with basic designs, layouts, and orientations. In this study, 12 hypothetical office buildings (linear, square (courtyard), and L-shaped) with both open and closed plans N-S and E-W oriented were simulated using DesignBuilder. The proposed retrofitting strategy succeeded in decreasing annual energy consumption by 46%–65% for all retrofitted cases. Four retrofitted cases met the nZEB target, these are the closed squared office building oriented E-W, closed squared office building oriented N-S, the closed linear office building oriented E-W, and open-plan linear office building oriented E-W. This study may be considered prototypical to encourage policymakers to urgently enforce existing energy conservation codes and set retrofitting measures, to start a national retrofit process of existing office buildings in Egypt