Evaluation and refinement of low cost automation system for naturally ventilated greenhouse

Abstract

Greenhouses are structures used for offseason cultivation of crops and also for obtaining maximum production from unit area. In greenhouses, crop growing environment as well as growing medium can be modified by adopting suitable technologies for microclimate control and water and fertilizer application. Manual controls of microclimate and water and fertilizer application are time and labour consuming and hence automation is required for the better greenhouse management. The study entitled “Evaluation and refinement of low cost automation system for naturally ventilated greenhouses” was conducted during the period July 2015 to February 2017 to modify the existing low cost automation system at ARS Anakkayam and also for its performance evaluation. Existing automation system has limitations such as it cannot manage temperature and relative humidity separately and also it cannot manage irrigation and fertigation. These problems were rectified in refined automation system. The refinement of the system was done by changing the microcontroller used in the automation system and also using a timer for the timely management of irrigation and fertigation. The refined system was capable of managing temperature and relative humidity separately and performing irrigation and fertigation operations inside the greenhouse. The refined automation system was tested without crop and with crop during three crop seasons with salad cucumber crop (variety Saniya) inside the greenhouse. The experiment was conducted inside a naturally ventilated greenhouse situated at the ARS, Anakkayam, under Kerala Agricultural University. For comparison, salad cucumber was cultivated inside another greenhouse which is manually controlled. Microclimate as well as crop data were collected from outside the greenhouse and both these greenhouses and compared. The temperature inside the AGH was less compared to NAGH and the relative humidity inside the automated greenhouse never exceeded above 70%. The yield and all other crop parameters were better in AGH compared to NAGH.