Installation and Connection of Hybrid Off Grid Inverter System to Develop Closed Greenhouses for Automatic Hydroponic Vegetable Cultivation
Keywords:
greenhouse, hydroponics, solar energyAbstract
This study aimed to design and develop a closed greenhouse constructed with clear polycarbonate sheets. The design integrates green energy for eco-friendliness. The researchers developed a greenhouse with a gabled roof measuring 4 meters wide, 8 meters long, and 3.40 meters high. The roof structure had a 15-degree angle on each side to accommodate six polycrystalline solar panels of 340 watts on each side, totaling 12 panels. Each side was connected in series and then in parallel, passing through a 5,500-watt inverter for off-grid operation without batteries, to reduce electricity usage during daylight hours (08.00–17.00). This system powered cooling fans, mist sprayers, and pumps for solution A and B fertilizers. The team experimented with vertically grown hydroponic green oak lettuce using the Deep Raft Technique (DRT) and tested the efficiency of the solar power system, which served as the primary energy source. The experiment with the cooling fan generated an average voltage of 226.7 volts and an average current of 0.19 amps. The test with the fertilizer solution pumps showed an average voltage of 226.7 volts and an average current of 1.13 amps. Both experiments allowed for temperature and humidity control inside the greenhouse through a smartphone-based automatic system. The experimental results from two cycles of growing green oak lettuce in the closed greenhouse revealed that the optimal number of vertical planting holes was 720 per cycle. This setup enabled the successful production of hydroponic green oak lettuce within the closed greenhouse.
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