Techno-economic impacts of using a laser-guided variable-rate spraying system to retrofit conventional constant-rate sprayers

Authors: MANANDHAR, ASHISH - The Ohio State University; Zhu, Heping; OSKAN, ERDAL - The Ohio State University; SHAH, AJAY - The Ohio State University

Submitted to: Precision Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/13/2020
Publication Date: 2/24/2020
Citation: Manandhar, A., Zhu, H., Oskan, E., Shah, A. 2020. Techno-economic impacts of using a laser-guided variable-rate spraying system to retrofit conventional constant-rate sprayers. Precision Agriculture. https://doi.org/10.1007/s11119-020-09712-8.
DOI: https://doi.org/10.1007/s11119-020-09712-8

Interpretive Summary: Compared to conventional constant-rate sprayers, the laser-guided intelligent variable-rate sprayers are expected to have significant reductions in pesticide uses while maintaining effective pest control. In this research, economic evaluations were performed based on field tests for the intelligent sprayers in comparison with conventional sprayers used for apple orchard spray applications in Ohio. A techno-economic model was developed for the apple orchards covering areas of 4 and 20 hectares, typical orchard sizes in the Midwestern states. The model incorporated cost for operation, equipment, fuel use, and labor during pesticide applications. Based on this model, annual cost savings of approximately $1,420 to $1,750 per hectare could be obtained by existing sprayers retrofitted with the intelligent spray technology for pesticide applications in the 4 to 20-hectare apple orchards. To put this estimation in perspective, the total savings in annual pesticide application costs could reach between $185 and 228 million by implementing the intelligent spray technology in a total apple production area of 130,309 hectares in the U.S. These savings could be even much greater if the environmental benefits were added to the total savings due to great reductions in pesticide losses as spray drift in the air and to the soil and water.

Technical Abstract: Specialty crops, such as apples, are vulnerable to insects and pathogens, and require higher pesticide input than row crops, a significant fraction of which is off-target loss, causing adverse environmental and socio-economic impacts. Advanced laser-guided variable-rate sprayer (VRS) can improve spray deposition uniformity and minimize pesticide waste, while maintaining efficacy against insects and pathogens. Despite these merits, retrofitting the conventional sprayer with laser-guided variable-rate spraying functions adds to its cost. Thus, the objective of this study was to analyze the techno-economics of the conventional pesticide sprayer retrofitted with VRS, in comparison to the conventional fixed-rate sprayer (CRS) for pesticide application during apple production. A techno-economic model was developed for the apple orchards covering areas of 4 and 20 hectares, which are common orchard sizes in the Midwestern states. The model incorporated cost for operation, equipment, fuel use, and labor, during pesticide application. The data were obtained from field tests at orchards in Ohio in year 2016 and 2017, literature, and the original VRS development team at USDA-ARS and Ohio State University. The results indicated that VRS reduces pesticide costs by 60-67%, pesticide application time by 27-32%, and labor and fuel by 28% compared to CRS. For larger orchards, VRS also reduced equipment requirement. Compared to CRS, overall annual pesticide application cost savings by using VRS were between $1,420 and $1,750 per ha. The payback time for using VRS was estimated to be between 1.1 and 3.8 years for apple orchards between 4 and 20 hectares in Ohio.