Optimizing solar energy-based energy consumption in atrium-designed residential buildings: An economic, environmental, and energy-centric evaluation

• Adding an atrium in various climates of Iran reduced energy consumption by 29.49 % and CO₂ emissions by 32.99 %. • Greater building height improved atrium performance due to better air circulation. • Best atrium performance occurred in cold climates; best PV panel performance occurred in warm, humid climates. • In climates such as Yazd and Urmia, combining atrium and solar panels achieved the highest energy savings. • A 20-year economic assessment showed that atrium integration in Urmia’s 10-story building yields a positive NPV of $19,408. The increasing global energy demand alongside the depletion of fossil fuel resources, has made optimizing energy consumption in buildings a critical challenge. This study investigates the combined performance of atriums and photovoltaic (PV) panels in residential buildings to reduce energy demand and enhance renewable energy utilisation. The research covers four distinct climatic zones in Iran: hot-humid, hot dry, mild humid, and cold and considers three building heights (2, 5, and 10 floors) to enable a comprehensive analysis. Using HOMER Pro and DesignBuilder software, the study evaluates both the environmental and economic impacts of the integrated system. By simultaneously assessing atrium design and PV integration across multiple climates and building heights, this study addresses a notable gap in previous studies. Results demonstrate that atrium incorporation can reduce annual energy consumption by up to 29.49 % and carbon dioxide emissions by up to 32.99 %, while delivering a favourable return on investment over 20 years. Moreover, combining atriums with PV panels significantly improves energy performance in challenging climates such as Bandar Abbas and Urmia, shortens the payback period and enhances economic efficiency. These findings highlight that climate responsive atrium design, coupled with photovoltaic technology, offers an effective strategy to improve indoor environmental quality, reducing energy consumption, and promoting sustainability in residential buildings.