A Method to Implement a Monitoring System Based on Low-Cost Sensors for Micro-environmental Conditions Monitoring in Greenhouses

Abstract

The precise monitoring of the inner microclimate of a greenhouse implies an increase of the production costs following the expensive needed sensor arrays. Currently, there is availability of low-cost sensors and cards for data storage and processing, but their application in real scale facilities is still under study. This research aimed to find a solution to manage and implement the outcome of various information (i.e. luminosity as well as air humidity and temperature) on the internal environment of a tunnel greenhouse to point out the most critical dynamics occurring during the growth cycle of basil plants in summer. Placing low-cost sensors inside a tunnel greenhouse made it possible to acquire data with an adequate rate (0.1 min−1) and spatiotemporal distribution throughout the facility. Data storage and processing took place thanks to an on purpose created weather station based on Arduino Yun Rev2 board. The highest variability of air temperature and moisture inside the greenhouse occurred when the solar radiation begins to heat the cover of the greenhouse (between 6.00 and 7.00 AM) and few hours after the maximum peak of solar radiation (843.4 ± 133.3 W/m2). Low-cost sensors combined with spatial fitting of the data provided insights about the effective microenvironmental conditions occurring on daily basis. This, implemented with IoT technologies, will be the base for the realization of economic monitoring systems.