Seasonal performance evaluation of a photovoltaic solar chimney: Experimental study under Iraqi climate conditions

• The maximum electrical power reached by the PV chimney was for the summer compared to other seasons. • The best electrical efficiency obtained was for the winter season compared to the other three seasons. • The highest overall efficiency of the PV chimney was for the summer season compared to other seasons, which reached (78.64 %). • The primary criterion for assessing the PVSC performance is its radiation intensity. Integrating photovoltaic solar chimneys (PVSCs) presents an innovative approach for generating electricity, though the effects of seasonal performance fluctuations warrant further examination. This experimental investigation focuses on evaluating a PVSC system's annual functioning, tailored explicitly to the Iraqi climate (35.21°N, 43.71°E). A comprehensive, full-scale prototype was diligently observed for four distinct seasons, spanning from summer 2023 to spring 2024, with data meticulously collected on a daily basis between 9:00 AM and 4:00 PM during clear-sky conditions. The findings revealed that the overall efficiency peaked in the summer months at an impressive 78.64% when subjected to solar radiation levels of 803 W/m². Conversely, the winter season recorded a standout performance in terms of photovoltaic electrical efficiency, reaching 14.58%, which can be attributed to cooler panel temperatures (50.53°C compared to 86.9°C in the summer). During summer afternoons, the chimney exhibited its highest airflow velocity of 1.84 m/s and kinetic power of 26.42 mW. This system demonstrated its dual capabilities, achieving a maximum electrical output of 392.4 W while simultaneously improving ventilation. Notably, radiation intensity emerged as the primary factor influencing the system's overall performance. These insights offer valuable empirical benchmarks for refining PVSC designs in arid climates, contributing to the understanding of long-term seasonal performance and fostering advancements in hybrid renewable energy applications.