Smart Environment Adaptation for Proper Greenhouse Cultivation: From Prototype to Sustainable Operation of Auxiliary Air-Cooling System

Traditional greenhouse cooling often relies on single-pass evaporative systems that exhaust valuable moisture and CO2 into the atmosphere. This research introduces a sustainable alternative by developing a laboratory-scale greenhouse that utilizes a closed-loop ducting system to recycle cool, humidified exhaust air back through the evaporative felt pads and water reservoir. Central to this design is an automated control architecture powered by an Arduino Uno and an SCD-30 NDIR sensor module. This low-cost integration enables real-time monitoring and autonomous regulation of fans and water pumps to maintain internal temperature, relative humidity, and CO2 concentration within optimal physiological limits. The system’s performance was evaluated against a conventional greenhouse model lacking recirculation and automated controls. Experimental results demonstrated that the modified model (smart) significantly outperformed the standard setup (traditional), achieving an improved temperature reduction by a higher rate of 1.45 °C, compared to only 1.03 °C in the traditional model, and a significant increase in relative humidity, reaching about 9.30%, compared to only 3.36% in the traditional model. While the traditional model experienced CO2 dissipation, the experimental system successfully retained and regulated Carbon Dioxide levels, increasing concentrations from 497 to 552 ppm. These findings suggest that integrating smart automation with air-recirculation infrastructure represents a potential trail for improving resource management in controlled greenhouse environments under arid conditions.