Thermal modeling for greenhouse heating by using thermal curtain and an earth-air heat exchanger

In this paper, a thermal model for heating of greenhouse by using different combinations of inner thermal curtain, an earth-air heat exchanger, and geothermal heating has been developed. The analysis incorporates the study of thermal performance of three-zone greenhouse. The calculations have been made for a typical production greenhouse in southern part of Argentina, available climatic data has been used. The thermal performance of a greenhouse having thermal curtain and an earth-air heat exchanger has been compared with a greenhouse having thermal curtain and geothermal energy. It is seen that the fluctuations in temperature in the vicinity of plants are comparable in the two cases. From the results, it is seen that an earth-air heat exchanger might prove an alternative source for heating of greenhouse when geothermal energy is not available. It has also been observed that, the increase in temperature of zone I is more for the greenhouse with geothermal than the greenhouse with an earth-air heat exchanger. (c) 2005 Elsevier Ltd. All rights reserved.