Performance evaluation of three different types of local evaporative cooling pads in greenhouses in Sudan

Abstract

This study was conducted in Date Palm Technology Company Limited, Shambat, Khartoum State. To evaluate performance of three types of evaporative cooling pads for greenhouses (celdek pads, straw pads and sliced wood pads), as compared to the conditions outside the greenhouses (control), for pads. Performance evaluation includes environmental parameters (temperature and relative humidity at 8 am, 1 pm and 6 pm) and crop parameters (length and stem diameter, leaves number and width, fruit length and diameter, fruit weight and dry matter and yield). The results obtained for the temperature at 8 am showed that there was no significant difference (0.05) inside the greenhouses, while a high significant difference between the conditions inside and outside of the greenhouses was found. Significant differences were found at 1 pm and 6 pm between all treatments as compared to the conditions outside the greenhouses, and the results obtained for relative humidity showed high significant differences at 8 am and 1 pm inside the greenhouses and between inside and outside the greenhouse, respectively, while there was no significant difference at 6 pm inside the greenhouses and between inside and outside the greenhouses. On the other hand, the results obtained for crop parameters showed that there were significant differences between all parameters inside the greenhouses and outside the greenhouses; however, the greenhouses with sliced wood pads gave the highest yield and the greenhouses with straw pads gave the least and conditions outside gave the lowest. This study indicated that the sliced wood pads are better than the other evaporative cooling pads.

Development and evaluation of low cost evaporative cooling systems to minimise postharvest losses of tomatoes (Roma vf) around Woreta, Ethiopia

“…Maximum temperature inside and outside the coolers was observed between afternoon and evening for both evaporative coolers during the study. This trend was also similar with results reported by other researchers (Ahmed et al, 2011;Dagtekina et al, 2009). The reduction in the variation of relative humidity over time inside the cooler compared to ambient conditions was an indication of the effectiveness of the cooler in maintaining high uniform relative humidity.…”

Energy Efficiency in Greenhouse Evaporative Cooling Techniques: Cooling Boxes versus Cellulose Pads

“…This material usually consists of a plastic grid, though it may also be composed of corrugated cellulose pads, vegetable fibers found locally [10][11][12], such as wood chips, coconut fibre, etc., or porous inorganic material [13] such as perlite, volcanic rock, etc. These materials are placed in such a way as to ensure that they present the maximum possible transfer surface and the minimum resistance to the passage of the airflow.…”

Assessment of evaporative cooling efficiency in greenhouses equiped with wetted porous plates

“…In order to evaluate and compare different evaporative cooling systems, various research studies have been conducted in the field [9][10][11]. However, limitations such as insufficient number of greenhouses with similar systems at the same location, and the high costs for conducting experimental research, have hampered the conduction of field studies covering a significant number of variables and factors.…”