Heating load analysis of the pit greenhouse

Abstract.

In Korea, heating costs are important for greenhouse farming due to cold temperatures in winter. Although tax exemption oils have been being supplied, the greenhouse farmers will be greatly affected by the rise in international oil prices. Therefore, there is a need to plan ways to reduce energy use costs. In this study, development of a new greenhouse model different from the conventional greenhouse type was attempted for heating energy saving. The developed greenhouse model was examined for possible crop growth and heating load for energy saving. The greenhouse interior temperature, humidity, and ground temperature were measured for the pit greenhouse and the control greenhouse. There was a slight difference in humidity, but there was no significant difference in air temperature or ground temperature. In addition, there was no difference in crop growth. As a result of the heating load analysis, the heating load data of the pit greenhouse and the control greenhouse were concluded to be matched, although the volume of pit greenhouse was as large as the depth of the ground. The heating load coefficient of the pit greenhouse and the control greenhouse was estimated to be 2.6W/m² ·°C. Therefore, the pit greenhouse was suitable for heating energy saving as well as for space utilization compared to a conventional greenhouse of the same height.