Digital workflow for nearly zero-energy high-rise office building design optimization at the district scale in Mediterranean context

Abstract

While the implementation of sustainable urban planning has proven to be one of the primary goals to reduce the climate change impact, the rapid adoption of nearly Zero Energy Buildings (nZEB) concept in the building sector is inevitable to reach that objective. Following this trend, this article focuses on the implementation of a parametric digital workflow to evaluate the energy performance of a nearly zero energy high-rise 23-storey office building in the climatic and urban contexts of Casablanca at the early design stage. In the scope of our study, Grasshopper-based digital workflow permits us to investigate the impact of 147 parametric building designs, which are generated by varying the building's shape factor and orientation on thermal cooling and heating demand and global solar energy production. The outcomes of this holistic methodology highlight the design trade-offs between energy efficiency strategies and energy performance of building-integrated photovoltaic (bipv) and photovoltaic (pv) systems, aiming to reach optimized nZEB. Moreover, the results of the study suggest that it is possible to reach an annual load match equivalent to 29.7%. The findings also underscore the significant role of the BIPV systems in shifting towards the goal of net zero energy, accounting for up to 64.43 % of the total solar energy output and contributing in total up to 17.62 % to the yearly self-sufficiency. In addition, the energy balance evaluation, when assessed on an hourly basis, reveals that the BIPV system significantly improves the daily load cover factor, achieving a value of 12.45%, and increases up to 20.62 % when considering also the rooftop PV, particularly during spring season. Finally, the capacity credit factor is improved by up to 31.27 %, which is a significant share of grid connection reduction compared to the same building relying totally on the grid for its energy needs.