// Agricultural Engineering International: the CIGR Ejournal. Manuscript EE 07 012; Vol. X. January, 2008. — 14 pp.A complete numerical model has been developed to investigate the potential of using the stored
thermal energy of ground for space heating with the help of an earth to air heat exchanger (EAHE) system integrated with the greenhouse located in the premises of IIT, Delhi, India. The analysis was based on quasi-steady state condition. Experiments were conducted extensively during winter period from November 2002 to March 2003, but the model, developed, was validated against the clear and sunny days. The performance of the system was evaluated in terms of total heating potential obtained from EAHE, coefficient of performance (COP) and thermal load leveling. The heating potential of the system has also been standardized by the characteristic curve for greenhouse similar to that of flat plate collector. Temperatures of greenhouse air were found to be on an average 7-8 0C more than the same greenhouse when operating without earth air heat exchanger. The temperature fluctuations of greenhouse air were also less when operated with EAHE as compared to without EAHE. Predicted and measured values of greenhouse air temperature in the model developed, exhibited fair agreement.
