Gene A Giacomelli

Gene A Giacomelli

Professor, Agricultural-Biosystems Engineering
Professor, Applied BioSciences - GIDP
Professor, Plant Science
Professor, BIO5 Institute
Primary Department
Department Affiliations
(520) 626-9566

Work Summary

Gene Giacmomelli's research focus includes controlled environment plant productions systems [greenhouse and growth chamber] research, design, development and applications, with emphases on: crop production systems, nutrient delivery systems, environmental control, mechanization, and labor productivity.

Research Interest

Gene Giacomelli, PhD, is the director of the CEAC, or interdisciplinary education, research and outreach program for greenhouse and other advanced technology systems. Here at the University of Arizona, he teaches Controlled Environment Systems, which is an introduction to the technical aspects of greenhouse design, environmental control, nutrient delivery systems, hydroponic crop production, intensive field production systems, and post-harvest handling and storage of crops. His research interests include controlled environment plant productions systems (greenhouse and growth chamber) research, design, development and applications, with emphases on: crop production systems, nutrient delivery systems, environmental control, mechanization, and labor productivity.


Fleisher, D. H., Ting, K. C., & Giacomelli, G. A. (1997). Computer model for full-scale phytoremediation systems using rhizofiltration processes. Paper - American Society of Agricultural Engineers, 1.


Microcomputer software was developed to provide decision support information for design and operation of a rhizofiltration system, a phytoremediation based technology utilizing plant roots to remove heavy metals and radionuclides from contaminated waters. A Michaelis-Menton based model was developed and incorporated into a series of algorithms which process information relevant to the system design of the rhizofiltration process. Physical components of the phytoremediation system - plant production, rhizofiltration, pre and post treatment of water, and post treatment of spent plant materials are coupled with engineering and biological aspects of systems design. An engineering economic analysis tool within the software allowed for analysis of the impact of critical design variables on system efficiency.

Chiu, H. C., Ting, K. C., Giacomelli, G. A., & Mears, D. R. (1996). Simulation of supplemental light control strategies in a single truss tomato production system. Acta Horticulturae, 440, 141-146.


In the single truss tomato production system (STTPS), plants are grown hydroponically in a greenhouse with a single cluster of fruit per plant. One major advantage of STTPS is the ability to achieve uniform fruit quality on a planned schedule with predictable yield. To achieve high levels of greenhouse space utilization and a consistent harvest, several generations of plants are grown simultaneously with the plants being spaced periodically to maintain maximum plant canopy cover of the growing area, thereby maximizing utilization of space and supplemental lighting. As the production period varies with the light received by the crop it is essential to control the amount of supplemental light provided the crops so that each will have a predictable harvest date. Simulation of the cropping cycle has been programmed in Visual Basic to provide a management tool for the scheduling of lighting and the design of the lighting system. This program is based on a previously determined relationship between light received by the crop between germination and first flower development and the time to harvest. It accepts location specific solar radiation data as a variable input and has been used to optimize scheduling for the New Brunswick, New Jersey location.

Kim, K., Yoon, J., Kwon, H., Han, J., Son, J. E., Nam, S., Giacomelli, G. A., & Lee, I. (2008). 3-D CFD analysis of relative humidity distribution in greenhouse with a fog cooling system and refrigerative dehumidifiers. Biosystems Engineering, 100(2), 245-255.


The distribution of humidity in a greenhouse was studied using three-dimensional (3-D) computational fluid dynamics (CFD). The calculations were validated using experimental data from a single-span greenhouse without plants. Two types of humidity distribution were considered: humidifying using a fog cooling system, and dehumidifying using refrigerative dehumidifiers in addition to a fog cooling system. The simulation errors of RH were 0.1-18.4% with a fog cooling system and 1.1-13.1% with a fog cooling system and refrigerative dehumidifiers at each observation point. Contour maps were obtained from the 3-D CFD simulations to locate any non-uniformity in humidity distribution. The use of refrigerative dehumidifiers reduced the overall difference of humidity between the middle and bottom zones of a greenhouse, but the local distribution of humidity was uneven, especially close to the dehumidifiers. This study suggests that the developed 3-D CFD model can be a useful tool in designing and evaluating greenhouses with various configurations. © 2008 IAgrE.

Romero, P., Giacomelli, G. A., Choi, C. Y., & Lopez-Cruz, I. (2006). Ventilation rates for a naturally-ventilated greenhouse in Central Mexico. Acta Horticulturae, 719, 65-72.


The design and operation of greenhouse structures suitable for specific climate conditions is critical, especially when greenhouse cooling is expected to depend entirely on natural ventilation. The ultimate goal of this study was to investigate the potential enhancement of overall ventilation rates by optimizing greenhouse design parameters such as the area of inlet and outlet vents as well as the type of the insect screen utilized and its area. The Computational Fluid Dynamics (CFD) approach was used, verified by experimental data. Numerical simulations showed that the area of the ventilation openings has a significant effect on the air exchange rate, which increased about 25% when the vent area was enlarged from 6 to 15% of the greenhouse ground area. Another potential design change, the removal of the insect screen from the roof vents, increased the ventilation rates by 25% as compared to the current design. Enlarging the area of the insect screen on the side walls showed no significant improvement in ventilation.

Giacomelli, G. A. (2008). Procedding of International Workshop on Greenhouse Ebviromental Control and Crop Production in Semi-Arid Regions: Foreword. Acta Horticulturae, 797, 5-.