If all vents and doors are closed when the fans operate, air is pulled through the wetted pads and water evaporates. It is concluded that the accuracy of the model is acceptable and with the methodology of selection of photovoltaic systems represent a reliable tool for calculus of electric power and electric energy consumed by the fans, which represent the main and initial design parameter of any type of photovoltaic system. Fan and pad systems consist of exhaust fans at one end of the greenhouse and a pump circulating water through and over a porous pad (Figure 2) installed at the opposite end of the greenhouse.
It was used a methodology for selection of photovoltaic systems in order to design grid-connected configurations systems capable of producing, at least, the whole of the required energy by three greenhouses with different areas. These results are: power of exhaust fans and their operating hours. The results correspond to a typical summer day with high solar radiation and showed that mathematical model can enhance the management of the energy for the cooling process. On the opposite sides of the fans, pad-walls are installed which are kept wet. A set of large fans blow air out of the greenhouse, causing a suction-draught through the greenhouse. As the name indicates, it uses a combination of wet-pads and ventilators. In order to address this problem, a mathematical model that predicts the greenhouse temperatures and ventilation rates, was calibrated with experimental data. The Pad & Fan cooling method is a widely applicable cooling system due to it’s simplicity. Today, there are no scientific tools to determine the electrical energy consumed by air exhaust fans. Fan and pad systems consist of exhaust fans at one end of the greenhouse and a pump circulating water through and over a porous pad (Figure 2) installed at. MicroCools system can be controlled to release fog only when necessary to meet the optimal temperature and humidity profile for each stage of the plants. This calculation aims to ensure that the cooling process is completely sustainable. Intending to increase the reliability of photovoltaic systems in agriculture sector, this work was developed to calculate the energy required by fan-pad systems for the cooling process in greenhouses.