Thermal environment inside mechanically ventilated greenhouses: Results from a long-term monitoring campaign

In totally mechanically controlled greenhouses, the main indoor environmental parameters are accurately controlled for maximizing the quantity and the quality of the production. This task is challenging because values of these parameters significatively differ within the enclosure, with some spots reaching values very far from the average ones. In this work, the results from a long-term monitoring campaign in a mechanically ventilated greenhouse for floricultural production are presented. In the case study, indoor air temperature and relative humidity were measured in several spots, with different acquisition time steps. The working schedule of the evaporative pads was also monitored. The results of this work show that the thermal environment of the greenhouse was not homogeneous, especially concerning the indoor air temperature values that vary significatively inside the enclosure. This variation is more evident especially during daytime due to the presence of high values of solar radiation. Furthermore, the acquired data showed that the indoor air temperature stratification is a not negligible phenomenon inside greenhouses and has to be considered when the probes for the climate control systems are installed inside the enclosure.