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. Ac-cordingly, 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 ...
