Technical Evaluation of the Use of Flat Panel Solar Water Heaters in Greenhouse Heating in the South of Kerman Province

In this study, the application of a solar system for heating a greenhouse of twin type with arched structure and single layer polyethylene coating was investigated. For this purpose, initially, the heating needs of the greenhouse were determined. Then, according to the obtained results, a flat-panel solar water heater with a collector of 6 square meters and a tank volume of 500 liters was selected and installed next to the greenhouse cucumber production unit to heat the air inside the greenhouse with 4 unit of 10-blade aluminum radiators. Then, using paired t-test, the results obtained in this greenhouse were compared with the conventional type in the area that had a diesel heater. The results showed that in terms of carbon dioxide, average temperature and relative humidity, there was no significant difference between the two greenhouses, but in terms of chlorophyll index and crop yield, there was a significant difference between the two greenhouses, at a probability level of 1 and 5 percent, respectively. Diesel had a higher average in these factors. Also, managing the four factors of minimum temperature, average temperature, chlorophyll content and maximum relative humidity in the greenhouse equipped with solar water heater and controlling the two factors of minimum temperature and chlorophyll content in the greenhouse equipped with diesel heater can improve photosynthesis and increase yield.