Based on the amount and duration of external temperature, degree day values are determined according to whether the selected equilibrium temperature is lower or higher than the air temperature. Degree day values are calculated according to the fluctuations in ambient temperature. It can be understood whether heating or cooling systems are necessary within the calculated periods. In this study, the meteorological data of Antalya region dating back many years and the temperature values suggested according to the cultivation periods of tomato in greenhouse environment have been used as material. The daily average temperature values recorded for many years have been compared with the equilibrium temperature values selected for the tomato plant thereby calculating the heating and cooling day values for each cultivation period. Tomato cultivation in greenhouses is carried out in 2 periods in the region in spring and autumn. At the end of these two periods, it was determined that the heating degree days in autumn were determined to be higher than that in spring. Whereas cooling degree days were determined to be greater for autumn cultivation in comparison with that of spring cultivation. Information regarding the energy consumption of an agricultural structure can be obtained beforehand via the ...
Greenhouses are agricultural buildings where production takes place throughout the year. In greenhouse cultivation, the objective is to ensure economically highest yield by means of adjusting the greenhouse indoor climatic conditions. During summer, cooling is needed in order to prevent overheating in greenhouse. The cooling in greenhouses is carried out via fan pad cooling systems. Hereby study aims at determining the effects of highest and lowest local humidity on indoor temperature changes, through detection of the influence of outdoor relative humidity on the system efficiency and cooling rates. The research is realised in the 24 m long, 10 m wide glasshouse in the city of Isparta. It is found out that temperature reduction values in greenhouse are highly influenced by the local highest and lowest relative humidity. According to the outcomes of the study, in a day when the outdoor relative humidity is low, temperature level rises around 6-7oC compared to a day with higher humidity; therefore, the outdoor relative humidity comes up as a significant parameter for improving system efficiency. It is concluded that the most suitable hours for starting the system is 9.00-10.00 a.m., when the temperature begins to increase, for a more cooling efficiency. ...
In this study, the heating and cooling conditions of the greenhouses in Antalya were examined and suggestions were made for solutions of the problems that emerged. The Simple Random Sampling Method was used in determining the number of enterprises to be surveyed. The number of enterprises to be surveyed was determined as 246 with a 90 % confidence limit and 10 % error rate. It was determined that the greenhouses enterprises surveyed were heating at 96.34%. It has been determined that the most commonly preferred type of heater in the region is the stove and that the stove is heated only to protect the product from frost damage. In accordance with the data obtained from the research area, it was determined that one stove was used for 1000 m2 greenhouse floor area. It has been determined that 92.68% of the surveyed greenhouse enterprises are trying to reduce the excess temperature inside greenhouse by natural ventilation. It was determined that both the sidewall and roof ventilation were made at 45.93% of the greenhouse enterprises where examined in the research area. It has been determined that the ratio of ventilation area to greenhouse floor area changes between 10 and 15 in 32.52% ...
The aim of this study is to determine the effects of insect net placed on ventilation openings in greenhouses on temperature, humidity and radiation energy from indoor conditions. In addition, the effects of insect net on the agents used in biological control have been tried to be determined. The study was carried out between November 2017 and May 2018 in Kumluca district of Antalya in 2 glass and 2 plastic greenhouses. Greenhouses; the glass greenhouse without insect net (GCG), the glass greenhouse with insect net (GNG), the plastic greenhouse without insect net (PCG), the plastic greenhouse with insect net (PNG) is named as. Temperature, humidity and solar radiation values were measured in greenhouses. According to the results of the research; It was determined that the recommended temperature values for pepper development are only suitable in January and well below the recommended values in February. In other production months, the average temperature values of with insect net greenhouses (PNG-GNG) used in ventilation openings were found to be higher than without insect net greenhouses (PCG-GCG). When the results of relative humidity values were examined, it was observed that the use of insect tulle in the greenhouses was lower than the control greenhouses. ...
This thesis was carried out in four greenhouses with arc roofs with a base area of 6 m2 and a side height of 2 m in the experimental area of Isparta University of Applied Sciences, Agricultural Research and Application Center. For this purpose, greenhouse with LED lighting (LED), Red-colored (RG) greenhouse, Blue-colored greenhouse (BG) and greenhouses with transparent covering material (TrG) were used as materials. The study was conducted between February and May 2019. In this study, the effects of different color cover material on the development parameters of radish were determined by measuring the temperature, humidity and solar energy values of the greenhouse. In order to do these measurements, sensors are placed in the greenhouses. Solar energy measurements were taken between 10:00-16:00 hours considering sunshine time. Temperature and humidity measurements were recorded for 24 hours. When the values obtained from TrG, BG, RG and LED greenhouses were examined, it was determined that the highest temperature value of the radish plant in the LED greenhouse during the growing period. Average greenhouse indoor temperature values were found to be between 13oC and 16oC in LED greenhouse, between 6.5oC and 15oC in COG, between 6oC and 14oC in BG and between 6.5oC ...
In this study, it is aimed to determine the effect of greenhouse cover material of different color on the number of heating (HDHN) and cooling degree hours (CDHN) and heating (HDH) and cooling degree hours (CDH) of the lettuce plant. For this purpose, the study was carried out in the CtrlG (Control transparent PE greenhouse), RedG (Red PE greenhouse) and BlueG (Blue PE greenhouse). The study was completed in 2018 at ISUBU research and application farm. The temperature values measured in the three greenhouses with the same dimensions were the material of the study. HDH, CDH, HDHNs, and CDHNs were calculated by examining the measured temperature values and suggested temperature values for the lettuce plant. By using these values, it was tried to determine suitable cover material during the growing period of the lettuce plant. It has been concluded that the use of colored covering material is more suitable in terms of energy needs in almost all growing periods of lettuce plants. By comparing the values calculated for RedG and BlueG based on CtrlG, the coefficients of variation were calculated to determine which data series or series were more similar to each other. According to the coefficients of variation, the ...
Greenhouses are artificial growing environments that can provide the growth factors required for the production of crop plants out of season. In these structures, the low temperature values that occur during the year cause losses in yield and quality because they are not suitable for plant cultivation. In order to be able to grow out of season in these periods, the amount of heat required by the plants should be provided with additional heating. In the study carried out to determine the amount of heat needed in greenhouses throughout the year for the provinces of Kırşehir and Kahramanmaraş, which are located in two different regions of Turkey, the heat requirements that will arise in the presence or absence of a thermal screen in greenhouses with the same characteristics were calculated. In the calculations, the most common tomato plant grown in both provinces has been considered. Accordingly, if the greenhouse temperature is kept at a constant temperature of 18°C throughout the year, the heat energy requirements that emerge during the year are 469.90 kWh m.-2 for Kırşehir and 254.71 kWh m.-2 for Kahramanmaraş. In the case of using a thermal screen, these values were calculated as 401.53 kWh m.-2 for Kırşehir ...
The thermal energy demand during the production period in greenhouses is important for determining the production economics and feasibility studies to be carried out. This is because evaluating future investments in the greenhouse sector requires accurate estimates of energy demand and costs. For this purpose, the heat energy required in the greenhouse and the heating costs were calculated, taking into account the meteorological conditions of the region, the optimum temperature demand of the plants and the technical specifications of the greenhouse. Two different cover materials were used to determine the heat energy requirement: polyethylene sidewalls and roof (PE) and polycarbonate sidewalls + polyethylene roof (PC+PE). In addition, calculations were made for 8 different greenhouse combinations, including different insulation statuses (poor, medium and good insulation) of these greenhouses without thermal screen and with thermal screens. As a result of the study, it was calculated that the amount of energy consumed was reduced by 4.5% when PC covering material was used instead of PE covering material as covering material for the greenhouse side walls. In greenhouses covered with PE and PC+PE covers, if well-insulated thermal screens are used, the amount of energy consumed will decrease by 23.1%-22.4%, respectively, compared to PE and ...
