Design, Modeling, and Optimization of a Dual-Season Solar Chimney for Energy Consumption and Carbon Emission Reduction: A Case Study in Tehran

Passive solar systems can reduce the energy use of buildings. This study evaluates a segmented vertical solar chimney integrated into an eight-storey residential building (۲,۱۷۶ m²) in Tehran, a cold semi-arid climate, for both seasons: in winter it preheats incoming air, and in summer it exhausts warm indoor air by thermal buoyancy. A DesignBuilder (EnergyPlus) model calibrated against utility bills was used to compare three chimney geometries and five vent arrangements. Five design parameters (chimney depth, height, glazing type, insulation thickness and absorber thickness) were then evaluated at three levels each with a Taguchi L۱۸ array, using signal-to-noise ratios and ANOVA. Across the ۱۸ configurations, the chimney reduced annual heating energy by ۲.۴–۴.۰% (۴.۲۸–۷.۱۴ MWh), cooling energy by ۱.۵–۲.۶% (۰.۴۰–۰.۶۹ MWh) and CO₂ emissions by ۱.۱۷–۱.۵۹ t. Chimney depth was the dominant parameter for every objective (۶۵–۸۰% contribution; p < ۰.۰۰۱), but heating and cooling favoured opposite levels: ۰.۳ m for heating and ۰.۵ m for cooling. Because heating dominates the annual balance, the configuration selected was a ۰.۳ m depth, H+۱.۲ m height, ۰.۵ cm absorber, ۸ cm insulation and double glazing. For this configuration the Taguchi model predicts a heating reduction of ۴.۲% (۷.۵۵ ± ۰.۲۳ MWh) and a CO₂ reduction of ۱.۶۰ t per year. These savings are modest relative to the uncertainty of the building model and should be weighed against the chimney’s embodied carbon.

کلیدواژه ها:

Segmented solar chimney ، Dual-season operation ، Building energy simulation ، Taguchi method ، analysis of variance (ANOVA) ، CO₂ emission reduction