, Shiva Tahmasbpourafshar 2
, Hamid Mortezapour 3
, Saman Khalilzadeh 4
, Hosseinhttps://orcid.org/0000-0001-5252-8016 Maghsoudi 5
2Department of Biosystems Engineering, Faculty of Agriculture, Shahid Bahonar University of Kerman, Kerman 76169-14111, Iran
3Department of Mechanical Engineering, Faculty of Engineering, Bozorgmehr University of Qaenat, Qaen 97619-86844, Iran
4Department of Mechanical Engineering, Faculty of Engineering, Higher Education Complex of Bam, Bam 76613-14477, Iran
5Department of Biosystems Engineering, Faculty of Agriculture, Shahid Bahonar University of Kerman, Kerman 76169-14111, Iran
Abstract
The increasing global demand for high-quality greenhouse products, coupled with the heavy reliance on fossil fuels for climate control, has created an urgent need for sustainable, renewable-based solutions in agriculture. Conventional systems not only consume large amounts of energy but also contribute significantly to environmental pollution and greenhouse gas emissions. This study experimentally investigates a novel
hybrid renewable energy system that integrates a windcatcher, photovoltaic-thermal chimney, and earth-to-air heat exchanger to provide passive heating and cooling for greenhouses. Experiments were conducted at Shahid Bahonar University of Kerman, Iran, using a lean-to greenhouse structure during peak summer (July-September 2024) and winter (January-March 2025) conditions. Vector linear regression was employed to develop robust predictive equations with broader applicability across different climates. Key performance parameters, including greenhouse temperature, ventilation rate, generated electricity, and the ratio of supplied electricity to consumed electricity (SECE), were measured and analyzed. Results proved a maximum temperature reduction of 21 °C in summer and successful maintenance of internal temperature between 19.5 °C and 22 °C in winter when outdoor temperature dropped to as low as 4.5 °C. The system achieved a ratio of supplied to consumed electricity exceeding 1, showing full self-sufficiency in meeting electricity demand, and delivered a higher coefficient of performance than most previously reported single- or dual-renewable systems. Energy and exergy analyses confirmed an energy-balance closure below 5% and second-law efficiencies of 0.32 in summer and 0.45 in winter. This study presents the first experimental demonstration of the configuration comprising a
triple-hybrid windcatcher, a photovoltaic-thermal chimney, and an earth-to-air heat exchanger for greenhouse applications, addressing a critical research gap in integrated passive renewable systems and offering a practical pathway toward sustainable greenhouse thermal management in regions with high solar potential and extreme temperature variations.
